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Posted by: realred914 Nov 13 2010, 08:08 PM

what are the trick mods for performance power when building a D-jet motor . it is a tired 2 liter that will be getting a big bore 2056 piston kit.

what are recommendations for valves, porting compresion , etc....

will be a driver car 91 octane gas, , have SS heater exchanger, and I do want heat.

what can be done during rebuild to beef up the power????

Posted by: rdauenhauer Nov 13 2010, 08:17 PM

check out the eng. FS in my signature .

Posted by: Bleyseng Nov 14 2010, 09:20 AM

My recommendation is
Raby cam and lifters-(9950 or ?)
Porsche swivel feet
CR 9 to 1
tight Deck ht 0.40
42x36 valves w/HD springs
Raby new 914 2.0l heads
balanced everything


115-120hp with Djet and SSI HE's

Posted by: realred914 Nov 14 2010, 10:58 AM

thanks for the info, what is done to a raby head? i got my stock 2 liter heads and plan to rework them with new seats and weld any cracks. does a raby head have additional work done on it?, if so what?

Posted by: Jake Raby Nov 14 2010, 08:57 PM

First of all we don't rebuild any OE castings, the majority should have been disposed of 25 years ago. All heads that we offer are based on NEW castings.

For details on what separates our cylinder head program from the rest, follow this link, then each head offering- I even have flow charts for all the offerings.
http://www.aircooledtechnology.com/index.php?option=com_content&view=article&id=77&Itemid=91

Or if you want to just build the best stock FI 2056 you could just buy my full engine kit that has heads and the entire combination as well as all machine and balance work complete.
http://www.aircooledtechnology.com/index.php?option=com_content&view=article&id=57&Itemid=67

Or download this general presentation
http://www.rdtlabs.com/Presentations/v2RAT%20Engine%20kit%20program%20main.pps

Then see the specifics of the 2056 kit for stock FI to include dyno charts here
http://www.rdtlabs.com/Presentations/2010%20Porsche%202056%20kit%20details.pps

Posted by: realred914 Nov 15 2010, 10:18 AM

No technical info on parts selection was found on these powerpoint presentations.

i am looking for specific things to do on a 2056 engine. I am told i have to pick the compression , valves sizes and such first, before ording a cam.

I am looking for direction in picking these things as I have not purchased anything except main bearings at this point, so I am open to all the options

I t would be nice to have some suggested parts list that would be compatable with the correct cam and such, thats what i am looking for.

anyone?

Posted by: Bleyseng Nov 15 2010, 11:31 AM

Look at this for head info on the LE180 -http://www.aircooledtechnology.com/index.php?option=com_content&view=article&id=82&Itemid=96-

this is fairly technical but there isn't a "How to Preformance rebuild 914 Heads for Dummies" youtube video that I know of its how Jake and Len make their living.

Raby 95-- cam/valve train upgrade kit works fantastic with Djet.
cylinders bored out to 96mm with new Keith Black pistons to match...

CR from 8 to 9 to one
Rods have notched for oil squirting
balance everything!

Really, if you just want to build without hassle the "Best" 2056 engine just order a kit as its all ready to assemble with parts that fit with the proper clearances. Buying parts from all kinds of different suppliers will create some difficulties but you will learn alot !

Posted by: realred914 Nov 15 2010, 12:00 PM

Ok got it now, thanks, hard for me to find the info on rabys site, he has a lot of stuff on it
see below:

"Technical specifications for the RAT LE 180-914 cylinder heads:

Head casting type- NEW 2.0L Bus castings modified to 2.0/914

Combustion chamber shape- exact digitized replica of the 2.0-914 combustion chamber

Combustion chamber volume- 56cc+/-

Spark plug location- 2.0 914 location. Plug relocated from conventional location to promote efficiency, chamber strength and aesthetics for 2.0 engine owners.

Spark plug diameter- 12mm, reduced from 14mm to enhance chamber strength and help resist cracking related to potential over heating (should it occur)

Valve sizes- 42mm Intake/ 36mm Exhaust

Port work- Fully digitized CNC machined intake and exhaust ports that flow within 2% of the OEM 2.0 914 cylinder head!

Valve type- Stainless Steel

Valve Springs- RAT single heavy duty. Will control valves to 6,250 RPM +/- dependant upon camshaft and valve train mass.

Valve spring pressures- 215#@ .500 lift/ 120# seated

Retainers- Chromoly steel

Intake manifold pattern- original 4 stud pattern, no alterations made. Port matched manifolds are not included in the price. Installer is responsible for port matching manifolds. OPTIONAL "3 studding" available at added expense
"


so what I gather is offered by raby is a new bus head modified to replicate the 2 liter 914 head with smaller diameter spark plug threads but same chamber and ports. and same valve sizes. does this seem right?

So it appears I can fix my heads to be more or less the same not sure if i will change the plug hole or not.

so the stock valves work with the raby cam (still have no idea which cam to choose, several are offered)


I also see Elgin cams offers some choices on performance cams that are D-jet compatible, (for example 330 cam(shown in bold print below)) has any one used these cams? It was suggested by Elgin to clearance some metal on the heads that support a stud (if I remember right) that should help performacne. has anyone done that modification?
Elgin Cams listing:......................................

"PORSCHE 914 PROFILES

On the 7208 and wilder grinds we recommend having a slot cut down the middle of the timing gear to create two rows of teeth. This helps reduce oil throw off and oil foaming at high rpms.

Lifters must always be reconditioned or replaced. Beware of aftermarket 914 lifters, some of them are of very poor quality.

INTAKE ROCKER ARM RATIO = 1.3:1 EXHAUST ROCKER ARM RATIO = 1.25:1



GRIND NO.
SEAT DURATION
CAM LIFT
LASH
APPLICATION

64508-H
258

258
.294

.294
I HYD.

E HYD
HYDRAULIC LIFTER.

WILL WORK WITH F.I.

6508-H
260

260
.292

.292
I HYD.

E HYD
HYDRAULIC LIFTER STREET GRIND A LITTLE ROUGH WITH F.I.

68508-H
274

274
.302

.302
I HYD.

E HYD
PERFORMANCE HYDRAULIC, MORE COMP, & GOOD EXH. SYSTEM.

914
255

254
.296

.282
I STD.

E STD.
STOCK SOLID LIFTER GRIND.

330-1
256

255
.296

.296
I STD.

E STD.
IMPROVED STOCK. MORE LOBE AREA THAN STOCK. GOOD W/ F.I.

6408-18
256

256
.296

.296
I STD.

E STD.
WIDE TORQUE BAND. A LITTLE ROUGH WITH FUEL INJECTION.

66508-19
266

266
.305

.305
I STD.

E STD.
CARBS REQUIRED. SMOOTH IDLE, 1500-4500 RPM.

M6708-18
268

268
.314

.314
I STD.

E STD.
REQUIRES CARB AND A GOOD EXHAUST SYSTEM.

7008-17
280

280
.333

.333
I STD.

E STD.
BIG BORE KIT, CARBS, 9:1 AND HEADER, 2000-6000 RPM

7208-17
288

288
.333

.333
I STD.

E STD.
BIG BORE KIT, 9.5:1, CARBS, AND HEADER 2500-6000 RPM

7207-19
288

288
.369

.369
I STD.

E STD.
HOT STREET - AUTOCROSS. 9.5+:1, 2500-7000 RPM.

7508-18
300

300
.350

.350
I STD.

E STD.
AUTOCROSS. 10.5:1, 3800-7300 RPM.

7708-17
308

308
.369

.369
I .008

E .010
FULL RACE. 11.5:1, 3800-7300 RPM.

Posted by: Root_Werks Nov 15 2010, 12:10 PM

Loose the D-Jet!

Posted by: realred914 Nov 15 2010, 12:31 PM

sorry not an option for me.


just wondering what other folks have done with valve sizes, head work, cam shafts, compression etc... for a 2056 cc motor that must run with D-jet

I am told my existing 2 liter heads are usable after some welding and we will be repalceing all eight valve seats. we can perform some chamber modificatins and porting as needed.

just want to get an idea of what you all have done in simular situation(keeping the D-jet)

I do understand that I can send my MPS to Bleyseng for recalibration (as tradisrad has done) to the new motor.

other than that I am pretty open to suggestions.

Posted by: Jake Raby Nov 15 2010, 01:03 PM

Partially. The smaller plugs make for stronger chambers more resistant to cracking.



But you'll be making a significant investment in a set of castings that are still 35+ years old and are on their ninth life. I believe in spending more money initially but ending up with a component thats fresh and still on its first life, seems like money better spent to me. thats the reason why ALL my new engines and kits use these same cylinder heads.


I work it differently.. You supply me with the specs of the engine, your RPM range and a ton more info and I select the cam from my library. Here we do not use the "one line description" for camshafts because no one understands these cams better than I do, since I developed each of them and have used them in complete engines so I know their characteristics when coupled to various combinations..

You might be better off going with Elgin, they let you pick exactly what you want. The only problem with that is most people have no idea what they really need. There is a very good reason why so many people have told you to buy my cam kit.

Posted by: tradisrad Nov 15 2010, 01:06 PM

I am happy with Jakes cam, but I got one w/o the push rods. The engine runs great and has nice power. Ken Jansen did the build for me.

Posted by: realred914 Nov 15 2010, 04:44 PM

i will get you the engine specs once i get the data from others results, compression changes for example also depends on the cam cgoice, so my static compression ratio plus the cam choice and some other factors help determine the actual dynamic compression ratio., got to select them togther both teh camand the compression , I dont want to pick a compression that may get a cam that compromises something else maybe???

open to any discusion on pros- and cons of the varius combonations with a D-jet compatble engine as the constraint.?????????????

Posted by: Cap'n Krusty Nov 15 2010, 05:58 PM

Over the last 37 (almost 38!) years I've used a number of camshafts that were advertised as D-jet compatible. None were. (I've not tried Jake's, but I respect his knowledge and the hands on practical research he's done to ensure his WILL work as advertised.) Many (most?) of the others have been designed by engineers who haven't used them in an emissions controlled environment, nor do they appear to have had any practical experience in driveability. The system expects to see a certain set of vacuum characteristics that come from the stock camshaft profile, and few, if any, offerings of the big names in camshaft grinding provide those characteristics. Web Cam doesn't, Norris didn't, Isky, the same, nor any of the others I've tried. They all run really fat at idle, have a flat spot you could play pool on, and are otherwise a PITA to tune and to drive.

Consider that, please, before you pick a cam. They're a REAL PITA to replace once you've decided I might just be right.

The Cap'n

Posted by: rdauenhauer Nov 15 2010, 06:04 PM

Not unless he decides to come back from Suriname
When he does Im at the front o' that line

Posted by: Jake Raby Nov 15 2010, 06:59 PM

I agree with The Cap'n... I tried all the off the shelf offerings with no success until I developed the 9550, 9560 and 9590 grinds back in 1999. They were all developed to have a very conservative opening event to enhance the vaccum signature that the MPS sees. This is VERY critical to proper operation.

I tried over ten variations of the first version which is based from the Web 73 grind, the lobe separation and exhaust profile are altered from that base grind.

I've sold about 1500 of these camshafts, about 60 of those were sold this year. Out of all those I've had two complaints, both from people who misconfigured the remainder of their engine around the 9550 camshaft. Thats the reason why I am so critical of the combination that my camshaft will be used in conjunction with.

Cam grinders aren't engine builders, they have no idea how their product couples to different head configurations, induction systems or exhaust systems. I tell the cam grinder what to grind, I don't ask them to recommend what I need. They are about the worst person to make the selection. I wonder how many of them drove a TIV powered car to work today?

Posted by: TargaToy Nov 15 2010, 09:23 PM

For you guys with experience, what kind of power could one hope to achieve with a fuel injected 2056 (D-Jet OR L-Jet) assuming the entire system was optimized as per Jake's recommendations? I've been following almost every string on the subject and it often seems the big hp numbers and drivability claims are from owners of carbed cars. Is there no hope to make 120-130 hp with a tuned EFI TIV? Is it the intake runners or the cams or what that are the major hurdle?

Posted by: Jake Raby Nov 15 2010, 09:37 PM

Here is the MOST I have ever made with stock FI.. typically the peak power is 4-6HP less than this and generally made at or below 5,500 RPM.

This combo was:
-2056cc
-KB 96mm P&C
-RAT 9560 cam
-.035 deck height
- LE 180 CNC heads
-8.8:1 CR
-Stock D jet with MPS tuning
-Tangerine Racing header in 1-5/8"

Posted by: TargaToy Nov 15 2010, 09:44 PM

That's good stuff, Jake.

How about with a 1911?

Posted by: draganc Nov 15 2010, 10:22 PM

@realred914, what is your budget?

you know that you will spend at least $4-6000 with the engine mods that you want, which will lead you to a max of 120hp.

if you want a lot of HP for your $$$ you should consider as well other options as a V8 or a subaru "upgrade".

Posted by: vsg914 Nov 16 2010, 06:09 AM

[quote name='draganc' date='Nov 15 2010, 10:22 PM' post='1395030']
@realred914, what is your budget?

you know that you will spend at least $4-6000 with the engine mods that you want, which will lead you to a max of 120hp.

if you want a lot of HP for your $$$ you should consider as well other options as a V8 or a subaru "upgrade".
[I/quote]
G[quote name='draganc' date='Nov 15 2010, 10:22 PM' post='1395030']
@realred914, what is your budget?

you know that you will spend at least $4-6000 with the engine mods that you want, which will lead you to a max of 120hp.

if you want a lot of HP for your $$$ you should consider as well other options as a V8 or a subaru "upgrade".
[/quote]
I disagree! I have all my parts and have started the build with jakes cam set and have less than $2500 invested

Posted by: Jake Raby Nov 16 2010, 07:49 AM

To those who are seriously dedicated its about much more than cost.

Retaining the stock FI and keeping displacement at 2056 allows the vehicle to remain very simple, just as simple as it was 35 years ago. Simple carries a lot of value and will carry more tomorrow.

As Gretzky said "Skate to where the puck will be, not where it was or where its at right now." The demographic of 914 ownership has changed and will continue to.

Posted by: tradisrad Nov 16 2010, 08:31 AM

He has a 914 with a buick V6. I think he wants his 4 to be quicker than mine, but I think he is quickly finding out that not a lot more can be done while keeping the stock F.I.
-realred you just need to get you car running and stop trying to squeeze out 2 more horses than me. You have the V6....

Posted by: realred914 Nov 16 2010, 01:01 PM

not limited on budget, just looking for bang for the buck that is good. spend what i have to spend to make it work. just lookingfor teh best value on parts and making it all work together to get nice driver perfromance. prefer lower rpm power over higher rpm power as I would rarely rev above 4000 almost never above 4500 rpm. good reliability and mpg is also important. so what ever it takes.

i got D-jet down and want to keep it cause i like it

when i want lots of power, I look to the 3.8 liter V6 car. this car is different

Posted by: Root_Werks Nov 16 2010, 02:56 PM

Ooooooooooor, you could just loose the D-Jet and go L-jet.

Posted by: draganc Nov 16 2010, 07:55 PM

@realred914, what is your budget?

you know that you will spend at least $4-6000 with the engine mods that you want, which will lead you to a max of 120hp.

if you want a lot of HP for your $$$ you should consider as well other options as a V8 or a subaru "upgrade".
[/quote]

I disagree! I have all my parts and have started the build with jakes cam set and have less than $2500 invested
[/quote]



@vsg914, can you list the parts that you have bought for $2500? How about new heads or head work? Balancing?
I have about the same amount invested in parts, plus balancing and ceramic coating. main bearings only are about $150 a set. Then you need/should refurb the old injectors, that's about $120 a set.
It's difficult for me to believe that a T4 overhaul is only $2500.
If you can do it please share your secrets. I would very much appreciate your input.

@ Jake, I’m sure that a lot of fellow club members are seriously dedicated to their 914, however, the budget is the budget. Unfortunately not everybody is able to spend $10k on a engine build.
I know you don’t cut corners and that’s good and is very well reflected in your great engine kits, however, the 914 was introduced to the market as a budget alternative to the 911.

Posted by: Jake Raby Nov 16 2010, 08:12 PM

And the 914 is still more of a budget minded vehicle than the 911... If budgets play such a key role why are people going out of their way to make the car a"mid-engined 911"? Use 911 brakes, 911 suspension and a 911 engine and what the car was developed to be is history... Not that those are bad things, it's just part of an argument about what the car was and what it is today.

There were times when the 914 made up a smaller portion of our net sales every year, primarily due to costs related to producing things at our level. This is no longer true and since 2007 their has been a huge difference in the percentages of our sales that are 914 specific. For many years VW converts were nabbing up 914 engines for their cars and while they still do this on a large scale the percentages have changed regarding where our engines are being applied.

Yes it's a reality that someone can spend 10k on a 4 cylinder performance engine for their 914 but atleast it'll make 150-175hp... How about a bone stock 356 engine that starts at 10k and might make 85 hp on a good day costing 15k??

Most of those who I've sold these engines to don't post here... They are readers and lurkers, but they want the car a certain way and that's what we deliver, no matter the cost.. If me and my team are going to exert 100 hours of our lives into a single engine, not to mention the incurred cost of developing that engines components and combination we will be compensated monetarily.. My schedule is booked through July of 2011 so people obviously feel that what we offer is worth the price and worth the wait.

It's not for everyone, I wouldn't like doing it if it was.

Posted by: realred914 Nov 17 2010, 10:16 AM

my engien should be near 2 grand parts and labour. rebuilt heads, all new seats spin balance, new bearigngs, new 96 pistons, bored cylinders. align bore case, re-plug oil passages.

will update when it is done

i am hoping to get some ideas on modifications to teh 2.0 liter within the realm of using D-jet. lets keep to that idea on this post, rather than pie in the sky engines

Posted by: vsg914 Nov 17 2010, 10:51 AM

Draganc, 2500 bucks includes everything, including head and all machine work. I don't know about the rest, but my bearings cost about half of yours. Will i tell you where i get them? Sorry, but no.

Posted by: tradisrad Nov 17 2010, 11:15 AM

I think he got his main bearing for about $100...

Posted by: Cap'n Krusty Nov 17 2010, 01:37 PM

Considering the fact that 914 cylinder head reconditioning can EASILY exceed $1500, not including valves and springs, it's my opinion that $2000 might be a bit optimistic.
And, as Jake says, you still have 35 year old heat cycled castings.

The Cap'n

Posted by: john rogers Nov 17 2010, 04:00 PM

There is a shop in the Venice Beach area, I think, named "NARW" and the owner raced a 2L type four in vintage events for a few years and it made about 120 to 130 HP and had a "stock looking" throttle body, FI brain, injectors, etc. I think the brain was done over by a shop in northern L.A. and used heavier injectors and the throttle body was honed a bit as the engine would easily rev to 7K RPM which is difficult to do if the FI system is stock. I used to have the contact info but it all went with my car when I sold it but that could be a place to start. But as some have said, anything will NOT be cheap!

Posted by: Root_Werks Nov 17 2010, 04:47 PM

Unlikely stock D-Jet trigger points for the injectors would stay accurate at 7k rpm's.

Posted by: stugray Nov 17 2010, 05:18 PM

vsg914,

"Will i tell you where i get them? Sorry, but no."

What kind of attitude is that for a forum where people help each other?

I am in the middle of trying to do the same as realred914: "build the best 2.0L D-jet that I can on a reasonable budget".

If I found a good source for parts or a trick to make the D-jet go faster, I would definitely post it....

There are mods that can be made to the ECU and the temp & pressure sensors.....

Maybe I'll tell you.... maybe not ;-).......

http://members.rennlist.com/pbanders/

If realred914 is constrained by sticking with the D-jet ECU, then his hands are tied ( as are mine ).

If one can make the mods, then one can install a megasquirt ECU and keep all of the other components the same for less than $500.

Stu

Posted by: Bleyseng Nov 18 2010, 04:50 AM

Even then the old rebuilt heads can and do fail, ask Dave Hunt!

Posted by: vsg914 Nov 18 2010, 06:41 AM

Stu,if i share my source with the world, i would no longer have that source. Do you think Jake, engman, James adams, or mikey would share all their r&d? I think not.

If you read some of my 3000+ post you will see what I share. There are several local guys that use my shop,tools, and my knowledge free of charge. I get parts for them and don't mark them up.

If that gives me an attitude, then yes I have one. Its not my fault if you are not as resouceful as me.

Capn, my heads were in good enough shape, and low enough miles, and my machinist is retired and works from his garage when he feels good enough to work. He doesn't charge much. Sometimes being old and knowing most everyone in town is a good thing!

Posted by: realred914 Nov 18 2010, 12:11 PM

could yo not bend the trigger points spring (or shim it) to increase tension to prevent bounce? (of course the wear blocks would wear faster)

Posted by: realred914 Nov 18 2010, 12:19 PM

If folks wont share data, please post elsewhere, some of these posts are not about info, there simply ads or boasting, and not at all helpfull to finding out which parts work well on a 2056 cc motor constrained by D-jet. I just want technical info on the components and assembly that make these motors better posted here.

Posted by: rdauenhauer Nov 18 2010, 04:00 PM

Im confused, you ask for detailed information yet you ignore anecdotal warning by members who have BTDT.
The 30 yr old analog FI *IS* your limiting factor.
Seems you have made up your mind already? What more do you need ?
Visit Brads site, educate yourself, spend your 2500. rebuild your eng. and let us know how it goes?
If you can pry more from some combo or tweeks no one has tried in 30 yrs you'll be all our hero.
(I think) Im like you I understand and like D-Jet. so have made the decision on the motor I posted above to to accept the cap in HP/TQ due to D-Jet, but have been eying DIY PEFI solutions for future application..
I only wish I had a chassis w/o issues that I could mate it to.

Oh.. and there is always the search function

Posted by: realred914 Nov 18 2010, 04:30 PM

What anecdotal warning Have I ignored?

Yup I want detail on modifications, within the realm of D-jet. but I dont see any warning to which you refer?????

PEFI, what does that mean?????

Posted by: HAM Inc Nov 18 2010, 04:38 PM

Here's the info you need for the internals from a DIYer who has been down this road.

Here's the info from a pro with a proven track record for the internals.



As for the D-Jet tuning there is a lot of info on this forum and some in this thread. As long as you don't try to re-invent the wheel you won't have any trouble getting what you want.

As a cautionary note if your budget for the internals is less than the good parts cost, especially the heads, save your money until you can do it right. These old heads are not very forgiving, and they are critical to good, trouble free performance!

Same goes for the cam and lifters. Aside from possibly getting the wrong lobe specs (despite what the card says), there are a lot of cams out there ground on the wrong blanks, improperly ground and mated to lifters that are not compatible. Buy the good stuff once and be done with it.

And don't forget to have your case decked by a competent machinist familiar with these engines. I assure you it needs it.

Posted by: realred914 Nov 18 2010, 06:24 PM

good points, I believe deck of case is being done but will confirm it.

looking at a full flow oil system. does anyone make a fitting to replace the the oil filter flange? I will be doing a remote filter and cooler (retian stock cooler also) it be nice to elimiate the oil filter flange arm thingy with block off plate with ports for supply/return hoses to the remote.

Posted by: realred914 Nov 18 2010, 06:28 PM

ps my under standing of the 911 swivil feet is that they have longer life and dont tend to deform which can thorw off valve adjustment as the stock feet do. is there any other benifit to them other than this factor?

Posted by: draganc Nov 18 2010, 09:01 PM

i wrote: "...you know that you will spend at least $4-6000 with the engine mods that you want, which will lead you to a max of 120hp..."

keywords 120hp = $4-6k.

i'm glad you can do the job for $2500 but i can't.

i'm posting about my experience and nothing else, and no i don't have +35 years of type 4 experience nor do i have a "...machinist is retired and works from his garage when he feels good enough to work. He doesn't charge much...".

since i learned a lot from this form i thought it would be the proper attitude to return some of my information and experience.

all the work i do on my 914, i do it for fun and because i enjoy it. and no i don't expect pros like jake, the capt'n and others to share all of their secrets, they have to pay thei bills as well.

as far as "...Will i tell you where i get them? Sorry, but no...." - good for you.

here is my secret: i got my main bearings (kolbenschmidt) in germany and with the euro/$ exchange rate they are not cheap. i even offered in the past to get some for club members and i sold a set in the past to a club member.

no further comments...........

Posted by: vsg914 Nov 19 2010, 06:18 AM

J[quote name='draganc' date='Nov 18 2010, 09:01 PM' post='1396028'


no further comments...........
[/quote]

Posted by: HAM Inc Nov 19 2010, 09:09 AM

The 911 swivel screws eliminate the friction loading at the valve/adjuster interface (if you think the unit loading is high at the cam/lifter just consider what it is at the valve/adjuster with its much smaller contact area) so there is no wear at that interface and therefore valve adjustments hold longer. It also all but eliminates the side loading of the valve which in turn all but eliminates guide wear if the rocker geometry is correct. Reducing guide wear will also contribute to less valve/valve seat wear.

In Bleysing's post he listed the cam he used as a 9950 or ? I'm pretty sure he used a Raby 9550. It is very popular with D-Jet users.

Posted by: realred914 Nov 19 2010, 12:26 PM

what is the lift and duration on the raby cams that folks are using? i what to get some comparisions on this, will make a chart of varius combos of cams and such.

Posted by: Bleyseng Nov 20 2010, 05:30 AM

Good luck finding out that data as a few years ago it was pulled due to some idiot copying it and posting it on his website.

Maybe Jake will email it to you.

Posted by: HAM Inc Nov 20 2010, 10:27 AM

I understand the desire to scrutinize the cam specs, but IMO you can save yourselve a lot of time and trouble and the possiblity of coming to the wrong conclusion about an option by simply letting Jake make the selection for you based on the performance criteria that he draws from you. He won't miss the mark. No one out there has done more R&D with the T4 in general and the D-Jet 2056 in particular.

You can then ask users of the same cam & combo as yours their opinions of the drivability and overall performance before making your final decision.

The combo you have outlined for your engine is a pretty tried and true one with a lot of folks running it. No need to complicate the process. Stastically speaking if you strike out on your own (by that I mean trying unproven components i.e. cam and heads) you are more likely to miss than to hit the target.

BTW, the #'s on a cam card tell very little of the complete picture, and the #'s from at least one very popular manufacturer of some very popular T4 cams are not what they read on a Cam Dr.

And also, Jake won't likely reveal the critical specs of his cam offerings. He clamped down on proprietary data years ago. You will get a card when you purchase the cam with lift and CL info for set-up purposes. Jake has plenty of business. If the fact that the product he is offering has been exhaustively tested and proven correct for a given application isn't enough for a prospective customer then he just lets them go there own way.

Posted by: realred914 Nov 20 2010, 10:35 AM

i tried getting info from him, it is a no go, he wont recommend any parts or configuration to me. I asked about that. Seems like he dont want to make the sale?????? I can't figure it out with him.

Posted by: roadster fan Nov 22 2010, 03:08 PM

The MPS. The issue is with the Djet or Ljet as it is not easily modified/tuned for performance gains. It is an old system that works great in a stock configuration but you are limited to tweaking the MPS. If you went aftermarket EFI the limit is your checkbook and tuning expertise with the type4.

Many have used Megasquirt, SDS, and other aftermarket EFI systems with good success. How ambitious are you? I think post #41 says all you need to know about the combo to use with D-jet.

Jim

Posted by: Jake Raby Nov 22 2010, 08:10 PM

I don't operate conventionally.. My arrangements aren't conventional and due to that they are not as thoroughly understood by general enthusiasts as they need to be.

Here you place the order, fill out my questionnaire and have a phone consultation with me and i choose the cam of mine that you NEED, you will then understand.

Sorry, if you are looking for a bunch of numbers and a one line description of what a cam is supposed to that you can choose from, you'll not get that here.. Thats just not what I believe in or how I operate. Doing things in the method I prescribe is how I have pleased thousands of people on these forums, and it damn sure wasn't easy. I understand my camshafts better than anyone.

The way I design cams is much different, you can't compare my offerings to others without comparing apples to oranges.

No, making a sale isn't important enough for me to not follow our procedures or release information freely to anyone who requests it, before they make a purchase. I'd love to help you and it isn't complicated at all after the order is placed.

Posted by: Bleyseng Nov 23 2010, 10:14 AM

They are both a challenge to adjust to "tune" but it can be done. In a way since they are the only way to set the AFR easier then a Modern EFI with nearly infinite options.