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cary
In putting Mark's engine back in and replacing the broken accelerator cable. It seems the cable isn't quite long enough to work/fit correctly. In the FI arrangement the cable crosses the engine at 45 degrees. In dual carbs it needs to come at the bar at 90 degrees. Which pulls the bowden out of the firewall. Which will allow water down the cable tube.

What have others done to work around this ?
rfinegan
Take a look by the pedal cluster and the pivot for the accelerator cable/clevis mine had the cable drop down(loop) under a bolt making the cable seem to short.. When I routed the cable correctly all was good. May not be what you are asking but took me a few hours to resolve my issue when I reconfigured my Tangerine linkages. It should have just bolted up again and was just to short


-Robert
somd914
QUOTE(rfinegan @ May 8 2016, 10:13 AM) *

Take a look by the pedal cluster and the pivot for the accelerator cable/clevis mine had the cable drop down(loop) under a bolt making the cable seem to short.. When I routed the cable correctly all was good. May not be what you are asking but took me a few hours to resolve my issue when I reconfigured my Tangerine linkages. It should have just bolted up again and was just to short


-Robert

I've used both hex bar and CSP bell crank systems with stock cables. Not sure what to tell you, perhaps rfinegan is onto something.
rhodyguy
Is the linkage on the rear of the carbs?
cary
Cable itself is long enough. But when I use the accelerator cable hole in the engine tin the bowden portion is too short to both bolt up to the cable mount on the engine and stay in the cable tube on the fire wall.

I was pondering relocating a different hole in the engine tin.
somd914
QUOTE(cary @ May 8 2016, 10:36 AM) *

Cable itself is long enough. But when I use the accelerator cable hole in the engine tin the bowden portion is too short to both bolt up to the cable mount on the engine and stay in the cable tube on the fire wall.

I was pondering relocating a different hole in the engine tin.

You got me thinking since it's been a few years, so I took a look... I routed my cable up between the tin and firewall then secured it, thus it fits through the rubber gasket around the engine bay seal.
cary
QUOTE(rhodyguy @ May 8 2016, 07:35 AM) *

Is the linkage on the rear of the carbs?


I'll shoot a couple pictures this after noon.

Here's what I originally found. Broken because it was too short. Held straight with a conglomeration of zip ties. This is the only picture I have.
Snapped the threaded tube in half.

Click to view attachment

This ones being replaced. I don't want the same thing to happen to the new one.
So I'm going to add a locknut (like MarkV) to weak portion right against the bowden end to give it more strength. Should solve the problem.
cary
QUOTE(somd914 @ May 8 2016, 07:44 AM) *

QUOTE(cary @ May 8 2016, 10:36 AM) *

Cable itself is long enough. But when I use the accelerator cable hole in the engine tin the bowden portion is too short to both bolt up to the cable mount on the engine and stay in the cable tube on the fire wall.

I was pondering relocating a different hole in the engine tin.

You got me thinking since it's been a few years, so I took a look... I routed my cable up between the tin and firewall then secured it, thus it fits through the rubber gasket around the engine bay seal.


I'm was thinking thats would be the BTDT work around. I think I'll go that direction too.
rhodyguy
I don't recall the inner sheath sticking out that far. Is this a new cable? I've always used the factory cable routing and tin grommet for the cable. When I had a triad linkage, the cable holder arm/bracket was at roughly the same height as the crossbar connection point. Never had to use 5 zip ties to keep it in place either.
cary
That ones in the garbage can. Busted and the barrel nut was stripped out.
MarkV
My set up might be different because of the a/c compressor. There is plenty of slack to move the cable up and down a couple of inches.

Click to view attachment
cary
That's where it needs to come from. That will give you the 3-4 inches of slack to get it dressed in there correctly.

Thanks ..........
SA-914
This is what I have so far. But the pedal feels like it's in a bind.
Darren C
WTF


SA-914 That bellcrank linkage geometry is ALL WRONG. Throw it in the trash!!

It's no wonder your having problems with cable length, the mount bracket is god awful and all wrong.
The binding is also because your running the cable out of stock lay-out.

The angle is completely wrong on the cable connection bracket and the arm doesn't look the right length either.

Throw it in the trash and make a new one, it will make a dog of a driving experience if left like that.

I've just posted a "bonus" how to. It's in my Build-off Challenge thread here:

http://www.914world.com/bbs2/index.php?sho...p;#entry2341877

(there's no point telling a guy to throw something in the trash if you can't help him sort out the problem!)
somd914
Looks like SA914 is running a CSP linkage system. Agree the cable mount is a bit questionable, and the bell crank geometry looks askew, but I wouldn't say throw it away, lots of us run CSP's linkage with no issues - personally I like the feel of my pedal more with dual carbs and CSP linkage than with stock D-Jet.

As for properly installing a CSP system, take a look at this:

http://www.csp-shop.com/technik/pdf/deeng/23951.pdf
SA-914
Somd914-you got any pics of your installed system? I'm running 40idf carbs. When I follow the 50% throttle rule and line ub with the case, it looks like my arms may be a bit short.
Darren C
From reading the installation manual somd914 kindly posted, your CSP linkage was designed to be used with their throttle arms on the carbs too !!! (why do this? it's more work for CSP to make arms for the carbs? why not make the bellcrank fit Weber arms? This is a common sense issue, "KISS" Keep it simple stupid! Using standard Weber arms on your carbs make its more universal, easier to install and removes additional manufacturing costs and reduces purchase price)
SA-914, your centre bellcrank arm will be too short on travel if you haven't got the CSP arms on your carbs too.
I can't understand why CSP made the carb levers shorter? and the bellcrank with shorter arms? this reduces mechanical advantage/leverage and makes for a larger force to operate putting extra strain on the cable and more force at your foot.

Anyways the CSP linkage is made for a throttle cable that runs in line with the crankcase join (front to back) Here lies its achilles heel. (running the cable away from stock layout causes length and binding issues)

My advice is to make a new bellcrank with the main cross arm that connects to the carbs set at 45 degress with carbs on throttle stop. (you'll need to adjust the rods to suit, may need shortening or lengthening) Then make the new bell crank arm for the throttle cable to sit at the correct angle to pull from the "stock" cable position.

You can probably retain the CSP mounting and vertical pivot, but you'll need to make a new cable mounting and bellcrank to get it right.
somd914
I can post a few pics tonight.

But for keeping it simple, I can say it didn't take long to install, perhaps an hour, I've been running it for three years, it has a much better feel than the old hex bar, and certainly is easier to synch carbs with than the hex bar. Seems simple enough to me.
Darren C
The KISS comment is aimed at CSP for bringing to market a product lacking 914 application or basic engineering forethought.

Don't even get me started on the empi/crossbar type linkage!

All these carb conversion linkages really are "the emperor's new clothes".

I've yet to see a properly engineered 914 carb conversion linkage for sale.
dcecc1968
When I switched to dual webers with hexbar and replaced my accelerator cable, the collective wisdom on 914 World agreed:
1) Don't use the hex bar, you'll never get your carbs synched right.

2) If you use the hex bar, you'll need to run the accelerator cable between the firewall and the engine tin and not the hole in the engine tin because the engines were never designed to have carbs.

3) If you choose option #2..... after you get frustrated from not being able to sync your carbs, contact Tangerine Racing and get Chris' cable system.

I'm still on option #2..... not frustrated enough yet, I guess.

Good luck.
cary
Dang, I didn't know that there was quite this big of an issue with the carb linkage.
I guess I'll need to drive Mark's car a bit.
On the syncing. I was waiting till I install the 2.2 in my project car to figure that out.
But if we have any issues. I'll get some help. I have a 30 year Porsche tech that would probably make a house call.
rgolia
Get the tangerine racing cable system...what a difference. You will never look back.

Click to view attachment


and then get the CSP airbox

Click to view attachment
somd914
QUOTE(Darren C @ May 9 2016, 07:15 AM) *

The KISS comment is aimed at CSP for bringing to market a product lacking 914 application or basic engineering forethought.

Don't even get me started on the empi/crossbar type linkage!

All these carb conversion linkages really are "the emperor's new clothes".

I've yet to see a properly engineered 914 carb conversion linkage for sale.


After reading your thread, your work is incredible, and thanks for sharing.

As for carb linkage and keeping it simple, in my many years of engineering I've learned budget, schedule, and market all play critical roles - compromises are a way of life and market share.

As for SA914, his system is easily remedied. Here are a few shots of my alignment - off a little (exaggerated by camera angle) but works fine, throttle response is good, pedal has a good feel, and easy to synch. First shot is idle, then approximately half throttle, and full throttle.

Click to view attachment
Click to view attachment
SA-914
Got it. Just need to shorten my bracket to get it closer and move it over to the other side of the block seam.
Darren C
Thanks for the kind comments.
I can understand your hope in making the CSP linkage you have “work to a fashion” which is a no cost option for you; but the title of the thread is accelerator cable related.
The fact of the matter is, the CSP linkage places the cable in line with the crankcase join, leading to having to re-route, bend and re-support the cable in an awkward way that will lead to length and binding issues. However “neat” you may think the CSP linkage initially looks, it isn’t a good product and will always have the inherent engineering faults that will cause issues.
As a very low cost compromise you could cut (hacksaw) off the short arm where the throttle cable connects, install the linkage and set the 45 Deg angle, adjust the rods to the carbs then weld the cut off short cable arm back on at a new angle in line with where the cable should run in a stock layout. You’ll need to make up a new small support bracket for the cable so that it can run at the natural angle it needs, to avoid all the issues.

RG,
The tangerine racing cable system is SHOCKING. Do you really think that that is good engineering??
Ok, you may go “ooooo” & ahhhhh” when you slap eyes on it, but really; its bloody stupid, over engineered and damn right dangerous.
Again your take off the Weber levers? Then fit pulley wheels with a counterbore in which to refit the lever retaining nut….so theres no provision then for the tab lock washer??
There is slotted brackets on which slotted brackets and eyebolts fit to hold the cable! This is BAD engineering and gives scope for the whole damn thing moving out of alignment.
You then link Carb A to B with a Bowden cable! So you are totally reliant upon Carb B’s return spring to keep the cable tension as well as return the throttle to idle when you lift off the gas pedal!!!
This in itself is plain stupid and dangerous as there is potential for not only imbalance in the control of the Twin carbs but also a chance that Carb B may stick open if the cable sticks or the return spring on Carb B breaks or weakens.
With age the Bowden cables will increase in resistance between the Carbs and to some minor extent suffer with heat expansion & contraction.
There is also a risk you run a cable off the pulley in a jam situation.
On rapid throttle operation the cable resistances will effect balanced “snap shut” responses between carbs. This will promote poor fuel balance and cause at best “popping” or at worst unwanted surge when you desire engine braking.
At least with a metal bar link rods you get positive shut off and proportional opening & closing between Carbs.
There is also the problem of running the accelerator cable to the first carb in this set up. The stock cable is either going to be too long or too short!

The whole Tangerine set up is intrinsically dangerous!
It’s a great example of “the emperors new clothes” engineering by someone without a clue of the big picture.
ThePaintedMan
QUOTE(Darren C @ May 10 2016, 03:25 AM) *

The tangerine racing cable system is SHOCKING. Do you really think that that is good engineering??
Ok, you may go “ooooo” & ahhhhh” when you slap eyes on it, but really; its bloody stupid, over engineered and damn right dangerous.
Again your take off the Weber levers? Then fit pulley wheels with a counterbore in which to refit the lever retaining nut….so theres no provision then for the tab lock washer??
There is slotted brackets on which slotted brackets and eyebolts fit to hold the cable! This is BAD engineering and gives scope for the whole damn thing moving out of alignment.
You then link Carb A to B with a Bowden cable! So you are totally reliant upon Carb B’s return spring to keep the cable tension as well as return the throttle to idle when you lift off the gas pedal!!!
This in itself is plain stupid and dangerous as there is potential for not only imbalance in the control of the Twin carbs but also a chance that Carb B may stick open if the cable sticks or the return spring on Carb B breaks or weakens.
With age the Bowden cables will increase in resistance between the Carbs and to some minor extent suffer with heat expansion & contraction.
There is also a risk you run a cable off the pulley in a jam situation.
On rapid throttle operation the cable resistances will effect balanced “snap shut” responses between carbs. This will promote poor fuel balance and cause at best “popping” or at worst unwanted surge when you desire engine braking.
At least with a metal bar link rods you get positive shut off and proportional opening & closing between Carbs.
There is also the problem of running the accelerator cable to the first carb in this set up. The stock cable is either going to be too long or too short!

The whole Tangerine set up is intrinsically dangerous!
It’s a great example of “the emperors new clothes” engineering by someone without a clue of the big picture.


I'm not even sure why I bother responding to rants like this... but here it goes.

1) You're bashing the designs of a valued business member here, without much basis. I believe Chris has sold well over 100 of his linkages, and several of us have put them on race cars. Not one single failure thus far, as far as I know.

2) Like most people who feel that their opinion is the only one that counts, you have bashed two different designs, but as yet have not provided your own solution to the market. You know, the only "correct" linkage design. Congrats on being able to fab your own version, but unless you're selling it, I don't see why you're so angry.

3) Run a cable off the pulley in a jam situation? Oh, you mean like ALL modern throttle bodies before the manufacturers went to fly-by-wire? confused24.gif

4) Chris's design does not only rely on Carb B's throttle return spring. If you took the time to understand it, both carbs still have their own return springs. I went ahead and added a second return spring to both as well out of my own choosing. But I never had any of the issues you describe before I did that.

5) The stock cable works fine. It is neither too long or too short.

Chill out. If you have no constructive criticism, or can't at least present it that way, then please just relax.
Darren C
QUOTE(ThePaintedMan @ May 10 2016, 03:59 PM) *

QUOTE(Darren C @ May 10 2016, 03:25 AM) *

The tangerine racing cable system is SHOCKING. Do you really think that that is good engineering??
Ok, you may go “ooooo” & ahhhhh” when you slap eyes on it, but really; its bloody stupid, over engineered and damn right dangerous.
Again your take off the Weber levers? Then fit pulley wheels with a counterbore in which to refit the lever retaining nut….so theres no provision then for the tab lock washer??
There is slotted brackets on which slotted brackets and eyebolts fit to hold the cable! This is BAD engineering and gives scope for the whole damn thing moving out of alignment.
You then link Carb A to B with a Bowden cable! So you are totally reliant upon Carb B’s return spring to keep the cable tension as well as return the throttle to idle when you lift off the gas pedal!!!
This in itself is plain stupid and dangerous as there is potential for not only imbalance in the control of the Twin carbs but also a chance that Carb B may stick open if the cable sticks or the return spring on Carb B breaks or weakens.
With age the Bowden cables will increase in resistance between the Carbs and to some minor extent suffer with heat expansion & contraction.
There is also a risk you run a cable off the pulley in a jam situation.
On rapid throttle operation the cable resistances will effect balanced “snap shut” responses between carbs. This will promote poor fuel balance and cause at best “popping” or at worst unwanted surge when you desire engine braking.
At least with a metal bar link rods you get positive shut off and proportional opening & closing between Carbs.
There is also the problem of running the accelerator cable to the first carb in this set up. The stock cable is either going to be too long or too short!

The whole Tangerine set up is intrinsically dangerous!
It’s a great example of “the emperors new clothes” engineering by someone without a clue of the big picture.


I'm not even sure why I bother responding to rants like this... but here is goes.

1) You're bashing the designs of a valued business member here, without much basis. I believe Chris has sold well over 100 of his linkages, and several of us have put them on race cars. Not one single failure thus far, as far as I know.

2) Like most people who feel that their opinion is the only one that counts, you have bashed two different designs, but as yet have not provided your own solution to the market. You know, the only "correct" linkage design. Congrats on being able to fab your own version, but unless you're selling it, I don't see why you're so angry.

3) Run a cable off the pulley in a jam situation? Oh, you mean like ALL modern throttle bodies before the manufacturers went to fly-by-wire? confused24.gif

4) Chris's design does not only rely on Carb B's throttle return spring. If you took the time to understand it, both carbs still have their own return springs. I went ahead and added a second return spring to both as well out of my own choosing. But I never had any of the issues you describe before I did that.

5) The stock cable works fine. It is neither too long or too short.

Chill out. If you have no constructive criticism, or can't at least present it that way, then please just relax.


Like most heated replies to opinion, you fail to correctly read and understand my concise observations and retort at a tangent that is not constructive.

I fully understand the fact that I’m sticking my head above the parapet here by stating that all the commercially available carb conversion linkage kits for the 914 are flawed in one way or another.
However, I certainly don’t in anyway want to make this a personal attack on any individual. Again I understand that the guy’s who make and sell these kits have done it with all good intention.
Unfortunately I feel that they could be so much better, and in pointing out the flaws they may be taken onboard and resolved.
Little has changed since the 1960’s with the twin carb conversion kits. Empi etc must have sold 1000’s of the hex bar kits over the years. In the cold light of day we all know they’re not great, yet they still make them and folks will still buy them. The quantity sold is no indication that they're any good, just that they fill a gap in the market for which there's a demand.
This is a Forum…..and as such I’m just venting my frustration as an engineer at the worlds acceptance of a compromise when things could be made so much better, from which everyone would benefit.
I don’t know any of the vendors from Adam, and my observations and opinion is not an attack on the person, its on the flaws of their product. I have no intention of mass producing the utopic linkage or cable kit to compete with anyone, I just wish to vent my opinion and maybe let the manufacturers take some of it onboard and improve their products at best. At worst if a single person/owner says “Ah, I get what you say about this or that issue you’ve raised” I’ll be content. I’m not here for a fight just to maybe open others eyes to the complacent acceptance of these products and the fact the issues can be easily resolved to make a mediocre product great.

It's always a hard pill to swallow when some stranger says "Geez your baby's ugly"
rhodyguy
If YOU can build a better mouse trap do so. Let it go George.

You've made much of what MIGHT happen. None of which have occurred in my experience, nor others using the cable linkage as far as I know. First hand experience speaks volumes. Engineering posturing? Not so much. Btw, you came off as a prat with your ranting.
rgolia
Well sorry I chimed in and thanks for defending Chris's product boys. All I have to say is that I have put about 75k miles on my 914 with carbs on it. I have used the csp type linkage, the hex bar linkage, and now the tangerine set up. The carb syncing has never been so easy, the throttle response never so good......and no popping that came along with the other linkages. Did I add a spring or two, sure just like George did. beer3.gif
Darren C
Ok, time out.

George,

Please change anger & rant you read in my posts for passion. I’m sorry you find my presentation harsh especially the way I express constructive solutions, but I’m a Brit and this is how we are (Cold). Our tongues can cut folk to ribbons when we are expressing praise or advice its a form of tough love.

Rhodyguy,

Please challenge the opinion, not attack the man unless you know him.

You seem like an intelligent guy, but we don’t know the first thing about each others experiences.
I’ve got almost 40 years experience with flat four engines and I’ve built many, many, street, track and drag strip VW & Porsche motors over the years. In my working career you may have briefly read in my Build-off Challenge that I lived in the US and worked on the Challenger Shuttle wreckage recovery and investigation in 86 thru 87. This gave me an obsessive compulsive outlook on engineering fault finding. This carried on in my work career with the work I did at EADS Astrium after NASA for the European Space Agency where we built military and commercial Satellites and developed projects for Mars Rover and Boeing to name a few. I then finally got my career in line with my passion…cars. I trained at Bentley Crewe in 2000 and now work at Rolls-Royce Motorcars Goodwood designing, developing and analysing complex engineering projects. From concept to design and now 10 year evaluations.
My engineering opinion and natural ability to just look at something and see potential fault/failure and remedy is highly respected by R-R, Bentley and Jaguar motorcars (who I did some freelance work for). I've been doing just that for so long, 30 years + now and can't help myself.
Here’s a small window into my working environment. This is the ONLY personal moving film footage that has ever been allowed by R-R to be published outside of factory approved filming in Area 51 deep within the R & D department; such is the respect R-R have for me. (I'm the guy at the end in the lab coat getting out of the car) This was the very first mule Wraith prototype car that was mocked up as a pre-production car. with pre-launch alloy design wheels and one of the 1st six interior trims to be built to the new design. No BS here check the dates I made the film that UK format for 5th March!

https://www.youtube.com/watch?v=2pcCBJiSFDg

I have a large collection of classic cars that I’ve been extremely fortunate to acquire along the way. I’m active in numerous car clubs (and offer advice worldwide as the "spares and technical officer" for the RREC,..... http://www.chichesterweb.co.uk/rrec/rr05officers.htm I'm also a renown and respected world concours judge with an eagle eye for detail. I once awarded poor marks to Arnold Schwarzeneggers car!) and run a small business from home called D.C. Shed Industries, (a little like Mark does at 914rubber) making unobtainium parts for classic cars and new improved parts for several marques that I’m passionate about. This I all do voluntarily and ALL income from the sale of the parts I donate to charity.
This gives me the knowledge to make constructive comments and have opinion on bringing products to the open market “half cooked” and to welcome all criticism, good, bad or indifferent with open arms that may lead to a better product for all.
Just today I’ve finished a new batch of parts for one club.
Link (go to page 16) and you’ll see this is not BS.

http://www.deloreaneurotec.uk/viewtopic.ph...;p=70293#p70293

I’m currently working at R-R on the finishing details and infrastructure for manufacture of new models to be launched in 2018 (to be confirmed)

So I think I can justify my experience which allows me the freedom to rant on the simple throttle linkage and cable issues of aftermarket 914 kits!

Rgolia,

I truly appreciate your experience, but you have just re-enforced my whole point.

By saying that you needed to add a few springs here and there as George has, it’s proved my point that the kits (made by whoever) just aren’t right and need modifications.

All,

I’m not seeking anything here, just acceptance that I have an opinion based upon experience, I’d never shoot my mouth off about something I know nothing about. If any of the vendors visit this site or if any of you know them, please get them to PM me, I’d be only too pleased to help them develop their products, free of charge.
Just please don’t attack me for airing my opinion. I'm a Brit, we mostly moan about stuff, that's what we do!
rgolia
Darren,
All good here. I understand where you are coming from. Continuous improvement is a good thing. beerchug.gif Cheers...and if you do some engineering for 914 parts I would be happy to be one of the first to try it.
rhodyguy
So, your bluntness can be acceptable and explained/justified due to nationality? You seem to interpret my bluntness as anger. I'm American by birth and Irish by genetics, but I still have to watch my tone and tenor. Or not. Depends on my mood.

Darren C
QUOTE(rhodyguy @ May 10 2016, 11:04 PM) *

So, your bluntness can be acceptable and explained/justified due to nationality? You seem to interpret my bluntness as anger. I'm American by birth and Irish by genetics, but I still have to watch my tone and tenor. Or not. Depends on my mood.


Sounds like my ex-wife...

:-)

Can we just kiss and make up now?
rhodyguy
Of course!

BUT, considering the other linkage offerings available for carb conversions, Chris' functions better. You'll have to trust us on that one.
Darren C
I'll give you that one.

But genetically you know you're 50% banana.
cary
Is it me, or is the bar style dual carb linkage pretty stiff? Finishing up Mark's car this am it just seems like it takes quite a bit pressure to push down the gas pedal.
Cable itself is silky smooth. I did convert to a lighter spring. Helps a little.

It feels like a drive to Medford would wear out your leg.

somd914
QUOTE(cary @ May 10 2016, 08:12 PM) *

Is it me, or is the bar style dual carb linkage pretty stiff? Finishing up Mark's car this am it just seems like it takes quite a bit pressure to push down the gas pedal.
Cable itself is silky smooth. I did convert to a lighter spring. Helps a little.

It feels like a drive to Medford would wear out your leg.


I recall the hex bar on my silver car was a but stiffer than my CSP linkage, but not as you describe.

The Revenna green car also a hex bar system but is extremely stiff. I removed one of the two return springs and now has a tendency to stick. Cable seems to run freely, and also note this system has the cable connection at the passenger side of bar next to the carb, not a center-mounted cable. So, the cable runs the factory path except for the left-hand bend towards the bar which is a large radius.

cary
I'll retract that statement/question. I didn't have a point of reference.
I just went out and tried the D-Jet in my DD. Its about the same. The carbs may be a bit stiffer, but not significant.
Darren C
Cary,
Sometimes you have to go with your gut feeling. The DD is a good but not fallible reference.
You need to consider several things in our 40+ year old cars.
Starting at front.
1, The gas pedal.
I’ve changed several of these over the years in my various 911’s and also in my 914 and got a whole new feel.
The metal hinges inside the pedal rust and go stiff so can affect the resistance and feel. The hinges can also wear and even break inside the rubber and you wouldn’t necessarily know. The pedal design also relies in part to the rubber moulded around the hinge to act as a natural return to the upright position when you let your foot off.
If you replace it, buy GENUINE Porsche, for a few dollars more you get a thicker steel inside and better quality hinge than the aftermarket copies.
2, Pedal set bushes.
If worn these will cause issues in smooth operation and increased friction.
3, Cable route at the pedal end and chassis tube.
It is possible to cross over the accelerator & clutch cables inadvertently when replacing them so one runs across another. You can’t see easily inside the tunnel and this can happen especially if the accelerator cable tube breaks free at the pedal end. Corrosion is an issue here as it causes friction and closes down on the cable if the tube is rusty.
4, Cable.
ALL cables wear. Most owners carryout a Carb conversion and use their old accelerator cable thinking it’s ok. Bowden cables wear the nylon sheath on the inside radius of any bend and the outside radius at each end of any bend and cable outlet from each end of a sheath. Over time if a cable is undisturbed you don’t really feel any difference as you get used to it and the change is so infinitely small. It only becomes an issue if the nylon sheath breaks somewhere (usually where the steel ferrule fits at the bulkhead) wears through, the cable sheds a wire or jams and the sheath external spring rusts out.
Cables also pick up dirt and dust and fray which can give resistance. I've had cables out of a car and they run free (making you think they're fine) refitted them and they bind under operational tension or when asked to lay in awkward routes.
The worst thing owners can do is oil these accelerator cables in good faith. This can swell the sheath, attract dust/dirt to quickly clog up and although you think you've solved an issue temporarily, long term its just made things worse.
The cable is a cheap item (in Porsche terms) and easy to replace, so if you're unsure how old your cable is and what condition it's in...just change it for peace of mind.

When owners carryout a FI to carb conversion, one big issue is moving an old cable around the engine bay to the new linkage mounting point. Just doing this itself can create a binding as the old worn cable is now bending/laying in a different position so any internal wear from where its “worn in and settled” over the years can be an issue
Cary, its difficult to have a good reference unless your reference is a car with all new parts down the chain. If you jumped in the car and thought “hey this pedal feels stiff” then 9 times out of 10 I’d say go with your gut feeling. Comparing it to an “unknown quantity” another DD is a starting point but certainly not to be relied upon.
Looking at it logically, on FI you have only one throttle body, one butterfly valve and 2 springs (dependent on year, there’s a coil on the shaft and a secondary emergency spring introduced a little later). On a carb conversion you have 2 spindle, 4 throttle butterflies, two coil springs, and additional springs that come with your linkage, and maybe more springs owners have added to get the throttles to return. Plus most linkages have friction points and odd mechanical advantages thrown into the equation.
It’s for this reason that I’d question your comparison with the DD against your gut feeling here.
If anything I'd say the DD with FI has an issue if its got the same heavy pedal feel/resistance as the carb conversion car!

Regards
Darren
yeahmag
QUOTE(Darren C @ May 10 2016, 12:25 AM) *

RG,
The tangerine racing cable system is SHOCKING. Do you really think that that is good engineering??
Ok, you may go “ooooo” & ahhhhh” when you slap eyes on it, but really; its bloody stupid, over engineered and damn right dangerous.
Again your take off the Weber levers? Then fit pulley wheels with a counterbore in which to refit the lever retaining nut….so theres no provision then for the tab lock washer??
There is slotted brackets on which slotted brackets and eyebolts fit to hold the cable! This is BAD engineering and gives scope for the whole damn thing moving out of alignment.
You then link Carb A to B with a Bowden cable! So you are totally reliant upon Carb B’s return spring to keep the cable tension as well as return the throttle to idle when you lift off the gas pedal!!!
This in itself is plain stupid and dangerous as there is potential for not only imbalance in the control of the Twin carbs but also a chance that Carb B may stick open if the cable sticks or the return spring on Carb B breaks or weakens.
With age the Bowden cables will increase in resistance between the Carbs and to some minor extent suffer with heat expansion & contraction.
There is also a risk you run a cable off the pulley in a jam situation.
On rapid throttle operation the cable resistances will effect balanced “snap shut” responses between carbs. This will promote poor fuel balance and cause at best “popping” or at worst unwanted surge when you desire engine braking.
At least with a metal bar link rods you get positive shut off and proportional opening & closing between Carbs.
There is also the problem of running the accelerator cable to the first carb in this set up. The stock cable is either going to be too long or too short!

The whole Tangerine set up is intrinsically dangerous!
It’s a great example of “the emperors new clothes” engineering by someone without a clue of the big picture.


To be frank... You have no idea what you are talking about.

The throttle levers stay on and are "pinned" to the pulleys.

The cable connecting the master to the slave is ideal as it doesn't change with heat or expansion. Once the slack is taken out you are more or less done.

All the standard springs for the carbs stay in place, so you are no better or worse than with a linkage. If one carb hangs open with either system you have a potential problem.

This setup is WAY smoother than my PERFECT CB hexbar set up. My balance and feel is perfect with this setup. Something I could never achieve no matter what I did with a hexbar setup.

I race the stuff Chris builds and appreciate his engineering greatly. Not a fan boy, just a user.
Darren C
Ok Aaron,

Lets look at what I wrote and what you replied….

1, To be frank... You have no idea what you are talking about.

You are perfectly entitled to your opinion I respect that, so let me answer.

2. The throttle levers stay on and are "pinned" to the pulleys.

I wrote, you take off the weber levers with a QUESTION mark as I was NOT 100% certain.
I wrote that in my opinion it was over engineered. Pinning pulleys to levers is over engineering. Like the bracketry to the carbs it's lazy engineering to have all those slotted holes and even more lazy to fit a pulley to a spindle instead of a lever, then leave the lever on and pin a pulley to that. The lever is only held on with one nut for heavens sake. Your point has totally confirmed my observation that its bad engineering.

3, The cable connecting the master to the slave is ideal as it doesn't change with heat or expansion. Once the slack is taken out you are more or less done.

A cable between master and slave I wrote “you’re totally reliant upon Carb B’s return spring to keep the cable tension” this is ok until a spring breaks. It is not fail safe like a solid rod linkage.

4, All the standard springs for the carbs stay in place, so you are no better or worse than with a linkage. If one carb hangs open with either system you have a potential problem.

We agree believe it or not. This is my point entirely because its a cable between A & B if any carb hangs open or its return spring breaks (carb B) you have a potential problem. Any throttle linkage needs to be intrinsically safe. This is why a fully cable system is not a good idea.


5, This setup is WAY smoother than my PERFECT CB hexbar set up. My balance and feel is perfect with this setup. Something I could never achieve no matter what I did with a hexbar setup.

Again I never said this set up wasn’t smooth, I never said it wasn’t better than the hex set up for smoothness or feel or ease of set up. I said it was worse only in its inability to fail safe as in point 4 that we both agree on. We both know the Hex bar system is poor.

I race the stuff Chris builds and appreciate his engineering greatly. Not a fan boy, just a user.

I understand fully that I’m against fans and friends of Chris or whoever makes whichever linkage. I have constantly maintained that I am not interested in the people behind these linkages, only to point out as an engineer, the areas in which these linkages can be improved for the benefit of all.

Again Arron I respectfully ask those of you who have issues with my observations to take a little time to read into and understand what I’m saying here rather than shoot me down based upon your interpretation of what you think I’m saying.
ChrisFoley
QUOTE(Darren C @ May 10 2016, 05:05 PM) *

If any of the vendors visit this site or if any of you know them, please get them to PM me, I’d be only too pleased to help them develop their products, free of charge.

You're just too smart for the rest of us Darren. dry.gif
However, none of your strongly worded opinion about my linkage kit is based in any semblance of factual (real-world) information.
It's unlikely I'd ever ask for advice (on any subject) from you after reading this thread.
KMA.gif
somd914
QUOTE(Darren C @ May 12 2016, 07:44 AM) *


If anything I'd say the DD with FI has an issue if its got the same heavy pedal feel/resistance as the carb conversion car!



I can say that I converted from D-Jet to dual carbs using the existing cable that was re-routed. My CSP linkage turned out to be somewhat lighter, better throttle feel, and returns faster in comparison to how the D-Jet was, though I'll admit this is a qualitative assesment as I didn't instrument the rig.

I'm not attempting to draw out an argument, just saying what my experience has been.
Darren C
QUOTE(Racer Chris @ May 12 2016, 10:46 PM) *

QUOTE(Darren C @ May 10 2016, 05:05 PM) *

If any of the vendors visit this site or if any of you know them, please get them to PM me, I’d be only too pleased to help them develop their products, free of charge.

You're just too smart for the rest of us Darren. dry.gif
However, none of your strongly worded opinion about my linkage kit is based in any semblance of factual (real-world) information.
It's unlikely I'd ever ask for advice (on any subject) from you after reading this thread.
KMA.gif


Hey Chris,

Finally.

Unfortunate everyone before you has muddied the water with what they think my intentions are here and a general consensus has been reached that is incorrect.
I just want to see better products for everyone, no more no less.

When reactions simmer down, have a think again, my doors always open.

Regards
Darren
rhodyguy
Muddied the fucking water? Dude, you tore the linkage up! Let us see...."bloody stupid" (tally ho!), "over engineered", "damn right dangerous", next "plain stupid" ( make up your mind!) and then dangerous again. Have you forgotten what you have written? My cable goes thu the tin, with a grommet, where it is supposed to, stays where it's supposed to at the firewall and operates nicely. My last entry on this one. One wonderful thing about the British (IMHO) is you can tell them to fuck off and nobody breaks a sweat. Calling someone a cunt works for both genders and as a general rule is no foul. There you have it....bob's your uncle.
Darren C
QUOTE(rhodyguy @ May 12 2016, 11:28 PM) *

Muddied the fucking water? Dude, you tore the linkage up! Let us see...."bloody stupid" (tally ho!), "over engineered", "damn right dangerous", next "plain stupid" ( make up your mind!) and then dangerous again. Have you forgotten what you have written? My cable goes thu the tin, with a grommet,where it is supposed to, stay where it's supposed to at the firewall and operates nicely. My last entry on this one. One wonderful thing about the British (IMHO) is you can tell them to fuck off and nobody breaks a sweat. Calling someone a cunt works for both genders. There you have it....bob's your uncle.


Hey Bananaman,

Are you sure you're not my ex wife?

Yes I tore the linkages up. All types in equal measure, no particular favorite.
Every now and then you have to shake the tree to clear the dead wood.
Got to admit it's made a hot topic out of it now.
Maybe that's what's needed to effect change or just make people look at things with a fresh perspective. Either that or just alienate me then....
rhodyguy
Ok one more since you have now made personal. As others might attest to, this is where it starts to get interesting. I didn't tell you to FUCK OFF! or call you a CUNT!!!. Simply observations from personal experience. One would presume that learned gentleman as yourself would understand the applications and the differences. Perhaps the contrary?

ZOIKS! "Bananaman". I don't know. I'm crushed.






















Wait for it.
















Nope.












Wait for it.

















Did your ex wife have a penis?
ThePaintedMan
QUOTE(Racer Chris @ May 12 2016, 05:46 PM) *

You're just too smart for the rest of us Darren. dry.gif
However, none of your strongly worded opinion about my linkage kit is based in any semblance of factual (real-world) information.
It's unlikely I'd ever ask for advice (on any subject) from you after reading this thread.
KMA.gif


av-943.gif That's why I love this guy! ^

I don't have to keep defending Chris' product. It works for me, and that's what I know.

Either order one of Chris' linkages and take the time to truly understand how it works before bashing it, or go back into your shed with your hacksaw and create some more of your product, try to sell it, and let's see who gets more business. Otherwise your argument is invalid. You're trying to help, I get it, but you lack tact and factual knowledge of other systems. Yours is probably great, but unavailable to others. Chris's is for sale, has been tested (works great), and he didn't start off by bashing others.
Darren C
QUOTE(rhodyguy @ May 12 2016, 11:58 PM) *

Ok one more since you have now made personal. As others might attest to, this is where it starts to get interesting. I didn't tell you to FUCK OFF! or call you a CUNT!!!. Simply observations from personal experience. One would presume that learned gentleman as yourself would understand the applications and the differences. Perhaps the contrary?

ZOIKS! "Bananaman". I don't know. I'm crushed.

Did your ex wife have a penis?


I know you didn't tell me those thing's directly rhodyguy, it's called "baiting me" (particularly the "nope & wait for it". Classic baiting) to add fuel to a fire and intended to make others giggle, snigger, cheer and actually think you did call me directly those things, and maybe to promote or encite someone else to do so directly in their next post. (because no one reads into the intention on the internet, just sees the words which is why we're where we are now on this thread). But I've been around the block, I kinda know you wanted to call me those things anyway and used the observation and experience as a convenient tool to deliver the elephant in the room.

My Bananaman respose is a non offensive word, light hearted reply to you trying to bait me. If you take it as a personal attack to be playfully called Bananaman, you need to lighten up a little and you're letting this thread get to you.
As for my wife having a gentlemans part, she thought she did sometimes. Thinking about it, it would have gone with her moustache though.

Paintedman, I have nothing against any of the folks who make these products.
It seems that if I highlight any issue where they could be improved (whichever way that opinion is expressed on whatever product) the drawbridges are raised and the arrows are fired by their supporters.
I get it.
What I don't get is why everyone has to take this personally when I'm talking about a product not a man, and then get so hot under the collar?
Is it because you don't think I appreciate that the vendors have gotten up of their behinds and invested their time and money in bringing to market a product?
Is it because you think I dont understand how tough that is?
Do you think that I have no appreciation of how many people they've helped out.
Is it because you think I don't realize that (apart from Empi) that they probably haven't made any money out of it?
Do you think I simply don't appreciate everyones gratitude for what they've done?

Trust me I do.

All of this toing and froing is unfortunately detracting from the linkage and cable issues.
There are good points made in this thread that are getting lost in the bun fight.
This is a real shame.
rhodyguy
Chum the waters. The sparkling lure flashes. Fish on!!! owned.gif blowup.gif
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