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914World.com _ 914World Garage _ Did someone say 914 rear hollow swaybar?

Posted by: Ira Ramin Nov 1 2004, 02:45 PM

Ok Brad, you’ve got my attention. Actually you had it all along and this project is finally getting close to the top of the new projects list. I’m finally looking at doing a 914 rear swaybar. The design would be similar to my existing swaybar designs with the following criteria. Target price will also be the same. Here is what I’m thinking so far.

1) Hollow chrome moly heat treated bar design.
2) Anodized 6061-T6 aluminum arms with slots for adjusting stiffness.
3) Adjustable droplinks with spherical bearing rod ends for eliminating preload.
4) Noncompliant bushings for the pivot points.
5) Bolt on design using all metric hardware, with no welding or cutting required.
6) Short droplinks to prevent contact with trunk on lowered cars.
7) Optional longer droplinks to allow mounting inside trunk.
8) Size will be about 16mm or 17mm equivalent stiffness and will be determined with testing.

I’m open to any suggestions, so feel everyone free to comment. Currently I’m trying to finalize the design requirements, come up with a realistic design solution, and determine if there’s a big enough market to justify moving forward. Unfortunately I don’t have a 914 to design around. Anyone with a 914 near San Diego interested in helping? Eventually I’ll also need some help with the testing. Initially, I’ll probably build three sets of prototypes and would like to get them on cars that are already sorted out and see a lot of track time. The test cars don’t necessarily need to be near by. At least one car needs to be relatively stock. I have a Weltmeister bar to start designing around, but could also use a factory bar to work with if anyone has one I can borrow or buy. This is your chance to get your opinions heard. Is there interest in a high quality 914 rear swaybar? What features would you like to see? Would anyone be interested in helping with a car to design around and with prototype testing? Target dates would be prototype testing in the spring and the 1st production run in the summer.

Thanks!
Ira

Posted by: Mueller Nov 1 2004, 02:54 PM

only thing missing is driver adjustable while in the driver seat smile.gif

seriously, I think it's a good idea, of course I've never driven a 914 with a rear bar and it seems that it used to be the 1st thing to get disconnected (cause "everyone" said it to be)......

it might be more popular with the track guys than the auto-x guys since very tight corners/open diff tends to favor no rear bar (from what I have read)..agressive street drivers could benifit as well.....

Posted by: Ira Ramin Nov 1 2004, 03:03 PM

Don't you need to go stiffer in the back to get the front to stick better on tight corners?

Posted by: SirAndy Nov 1 2004, 03:13 PM

QUOTE(Ira Ramin @ Nov 1 2004, 02:03 PM)
Don't you need to go stiffer in the back to get the front to stick better on tight corners?

yes, but on AX at tight corners, cars with a rear bar tend to lift a wheel off the ground and if you don't run a LS, you're soooo out of luck ...

having said that, i'd buy one!
one thing i always hate is when you don't have any markings on the slider for the droplink.
i always have to measure left right to get them close, would be nice to have a few lines (think ruler) to make that easier ...

smilie_pokal.gif Andy

Posted by: Mueller Nov 1 2004, 04:24 PM

QUOTE
i always have to measure left right to get them close, would be nice to have a few lines (think ruler) to make that easier ...


Andy, you do not have to get both sides even, in fact, you could just leave one side alone and only adjust the other side....the Carrera GTs rear bar (and possibly the front one as well, I have not looked at mine yet, LOL) is only adjustable on one side.

I do like the idea however of having some sort of "markings" or easy referance method for adjusting.

Posted by: seanery Nov 1 2004, 04:27 PM

IRA,
I'd be up for one late next year for Bluecar, front as well.

Posted by: Reiche Nov 1 2004, 04:31 PM

Ira:
My brother has an uninstalled rear bar he might let you borrow. He is in O-side. I have been trying to get him to join but he hasn't yet. PMing you his contact info.

Posted by: Aaron Cox Nov 1 2004, 04:45 PM

if its anything like your fronts, it'll be a great product!

i do have a question regarding my setup tho.

my car is lowered a bunch. optimal swaybar geometry is when the arm is parrelel to the ground. i can only adjust each side .5" in without the arms pointing upward instead of level with the ground. almost like the threaded sleeves need to be shorter.

Posted by: Ira Ramin Nov 1 2004, 05:14 PM

Aaron,
Having the arms parallel to the ground is optimal, but being slightly off is ok. The drop links should be able to go at least 1” shorter than stock. I designed them to fit my 911, which is very low. They need to be set almost as short as they’ll go to keep the arms level on my car. Are yours set as short as possible? I’m wondering if 914’s are slightly different. Please send or post a picture if you can. How much shorter do you think they need to be? There’s probably some room to make them a little shorter and still work for cars that are higher. Is anyone else seeing this problem?

Thanks,
Ira

Posted by: Aaron Cox Nov 1 2004, 05:17 PM

QUOTE(Ira Ramin @ Nov 1 2004, 04:14 PM)
Aaron,
Having the arms parallel to the ground is optimal, but being slightly off is ok. The drop links should be able to go at least 1” shorter than stock. I designed them to fit my 911, which is very low. They need to be set almost as short as they’ll go to keep the arms level on my car. Are yours set as short as possible? I’m wondering if 914’s are slightly different. Please send or post a picture if you can. How much shorter do you think they need to be? There’s probably some room to make them a little shorter and still work for cars that are higher. Is anyone else seeing this problem?

Thanks,
Ira

yeah. theyre as short ass possible. ill see if i can get a pic this weekend.

had to install it .5cm lower to clear the gas tank to.

Posted by: SirAndy Nov 1 2004, 05:30 PM

QUOTE(Ira Ramin @ Nov 1 2004, 04:14 PM)
Is anyone else seeing this problem?

yes! (and i thought i was alone) ...

i can post pictures later tonight from home.
type.gif Andy

Posted by: Ira Ramin Nov 1 2004, 05:31 PM

I haven’t heard about needing to install the bar lower to clear the tank. I have some thin jamb nuts that may allow enough additional adjustment to solve your problem. PM me your address, and I’ll send you some.

Thanks

Posted by: trekkor Nov 1 2004, 07:52 PM

Hey!

I want to be the tester guy. boldblue.gif

I'll drive it hard and often a/x, track and street. driving.gif

I'll post pics of the stock rear bar with the muffler off for easy viewing.
I had too turn my sway bar over to get more travel, as my car is VERY low and the bar was whacking the body all the time.

Regarding wheel lift: the addition of the rear bar and Engman's long kit eliminated front lift completly due to HUGE front bar.

KT

Posted by: Ira Ramin Nov 1 2004, 08:38 PM

QUOTE
I had too turn my sway bar over to get more travel

Do you mean that you put the rear bar in the trunk? A shorter drop link will help prevent it fron hitting, but there's a compromise.

Your pictures will be very helpfull at this point.

Posted by: TimT Nov 1 2004, 08:40 PM

Ira, make all your sway bars hollow!!! all that extra weight I carry with solid bars..

Posted by: ppickerell Nov 1 2004, 09:08 PM

I could laser mark the graduations!

Posted by: SirAndy Nov 1 2004, 09:34 PM

QUOTE(Ira Ramin @ Nov 1 2004, 07:38 PM)
Do you mean that you put the rear bar in the trunk?

no, you can flipp the stock bar over and gain more clearance without having to route it through the trunk ...

smash.gif Andy

Posted by: drew365 Nov 1 2004, 09:37 PM

I have a Weltmeister that I'd love to get rid of. I do a lot of track days so I'd be happy to be a tester. I'm not sure what size the Welt is but I would probably want one slightly smaller as my Welt is set a near full soft. I have big rear springs, 400#.

Posted by: Ira Ramin Nov 1 2004, 09:40 PM

Patrick,
I'd be very interisted in talking to you about laiser marking graduations. I've managed to not increase my swaybar prices in over four years. I've always wanted to do laiser marking but am worried about the cost. Send me your number and we can talk.

Thanks

Posted by: Ira Ramin Nov 1 2004, 09:51 PM

Andy,
If the Weltmeister bar fits better flipped over, why wouldn’t it always be mounted that way. Does anyone have a picture of this?

Drew,
What are you running up front to balance out those springs? I’ve seen your car at Willow before. Where are you located?

Tim,
Hollow of course.

Posted by: ppickerell Nov 1 2004, 09:54 PM

Ira,
Email sent.

Posted by: trekkor Nov 1 2004, 10:03 PM

QUOTE(Ira Ramin @ Nov 1 2004, 07:38 PM)

Do you mean that you put the rear bar in the trunk?



The bar is in the stock position. Mounted above the exhaust.
Installed in one position the bar has only 1" of travel.
Installed upside down from the previous you get 3-4" 's.

The bar is curved on the arms so it does matter which position it is in on a LOW car.

KT

Posted by: drew365 Nov 2 2004, 09:11 AM

QUOTE
Drew,
What are you running up front to balance out those springs? I’ve seen your car at Willow before. Where are you located?


Ira; Up front I have 22mm torsion bars, 23mm Smart bar, Koni adjustable shocks. My rear Welt is a 16mm. I am in the Van Nuys area of the San Fernando Valley.

Posted by: trekkor Nov 2 2004, 12:47 PM

here's some pics of the rear susp.

2-3 inches of travel with bar in this position.
.5 inch upside down.


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Posted by: trekkor Nov 2 2004, 12:53 PM

here


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Posted by: trekkor Nov 2 2004, 12:58 PM

'gain


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Posted by: trekkor Nov 2 2004, 01:00 PM

last


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Posted by: Brad Roberts Nov 2 2004, 01:31 PM

Thanks Ira. You will be contacted very soon about your products for our ecomm.

Yes. The secret to keeping your STOCK 914 rear bar form hitting the trunk floor.... flip it over from stock.


B

Posted by: Britain Smith Nov 2 2004, 04:18 PM

You get even more travel if you install upside down and attach the droplinks going down...like this. It works just the same.



-Britain


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Posted by: Aaron Cox Nov 2 2004, 06:16 PM

hmmm... almost looks like you could hook the swaybar directly to the trailing arms idea.gif

Posted by: Dave Bell Nov 2 2004, 07:36 PM

I'm interested in the rear sway... from you IRA... love the front bar I have.

Keep us posted and give us a group buy on the new item before it hits the distributors they can get pissed off about it.

- Dave

Posted by: Brad Roberts Nov 2 2004, 07:37 PM

That distributor will probably be US Dave... LOL

B

Posted by: trekkor Nov 2 2004, 07:40 PM

Britain, does the bar loses any of it's effectiveness pushing instead of pulling?

KT

Posted by: Brad Roberts Nov 2 2004, 07:41 PM

The bar doesnt care which direction it is being pulled or pushed. I told you about this last week.


B

Posted by: trekkor Nov 2 2004, 07:50 PM

Yes, I remember. I even made the changes on my car before the a/x.

I'm just curious if changing the drop link angle like that is like softening the bar. Full travel but, less overall bar action.

KT

Posted by: Brad Roberts Nov 2 2004, 07:52 PM

Bar action didnt change. You didnt change the effective length of the bar...



B

Posted by: Aaron Cox Nov 2 2004, 07:54 PM

QUOTE(Brad Roberts @ Nov 2 2004, 06:52 PM)
Bar action didnt change. You didnt change the effective length of the bar...



B

the angle changed tho. so you lose some advantage, droplinks work best when pointed staright up

Posted by: trekkor Nov 2 2004, 07:55 PM

Not my bar...Britain's, in the picture.

KT

Posted by: Brad Roberts Nov 2 2004, 07:58 PM

The drop link length didnt change either. I see NO way that the effective rate changed. The angle is the same just opposite.


B

Posted by: Aaron Cox Nov 2 2004, 08:00 PM

be right back with some illustrations.

Posted by: McMark Nov 2 2004, 08:00 PM

QUOTE(acox914 @ Nov 2 2004, 05:54 PM)
QUOTE(Brad Roberts @ Nov 2 2004, 06:52 PM)
Bar action didnt change. You didnt change the effective length of the bar...



B

the angle changed tho. so you lose some advantage, droplinks work best when pointed staright up

*Armchair Engineer Says*

Not necessarily straight up, more specifically, parallel to the path of travel of the suspension pickup.

Posted by: trekkor Nov 2 2004, 08:05 PM

In my pic the link is parallel to the shock, while Britain's is not.

His link is kicked slightly toward the back of the car.

confused24.gif

Wouldn't it take more force to move Britain's link the same distance as mine?

I don't really know anything. lol2.gif
Just making noise.

KT

Posted by: Aaron Cox Nov 2 2004, 08:08 PM

ok here goes. (armchair engineer LMAO!!!)
seems like shortening drop links to make them parellel to suspension movement would be ideal.

think front sway bars: works best when arm is parallel to ground.


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Posted by: redshift Nov 2 2004, 08:10 PM

Sorry to get off-topic, but

SHUT UP AARON.


Sorry...


M

Posted by: Aaron Cox Nov 2 2004, 08:11 PM

dammit miles! your meds are on the table, take them!!!

be a good boy and go to bed!

Posted by: Brad Roberts Nov 2 2004, 08:11 PM

I dont agree about the front bar working "better" with the arms parrallel... lol

B

Posted by: Aaron Cox Nov 2 2004, 08:12 PM

QUOTE(Brad Roberts @ Nov 2 2004, 07:11 PM)
I dont agree about the front bar working "better" with the arms parrallel... lol

B

im sorry. you lose mechanical advantage when they arent parralell confused24.gif smile.gif

wheres CF bob when you need him? hes a physics guru....or even alfred. dont make me do it! laugh.gif

Posted by: redshift Nov 2 2004, 08:13 PM

I have enough xanax to pack a Mack truck in a boxcar, and use the xanax for popcorn.

wacko.gif

Posted by: Brad Roberts Nov 2 2004, 08:16 PM

The rear links are not straight up and down when the rear bar is in its stock location. They are angled just like in Trekkors pics.. the angle doesnt change when you flip the bar over.

Can you tell me how much mechanical advantage is lost ?

Honestly I dont care. I adjust the bars as needed... doesnt matter whether they are parrallel or not. I dial them according to what the car needs for that given course.


B

Posted by: Aaron Cox Nov 2 2004, 08:24 PM

QUOTE(Brad Roberts @ Nov 2 2004, 07:16 PM)
The rear links are not straight up and down when the rear bar is in its stock location. They are angled just like in Trekkors pics.. the angle doesnt change when you flip the bar over.

Can you tell me how much mechanical advantage is lost ?

Honestly I dont care. I adjust the bars as needed... doesnt matter whether they are parrallel or not. I dial them according to what the car needs for that given course.


B

the angle of the "arms" and drop links have alot do do with it.

you get less rotation of the bar, from non parellel arms.....

cant tell you how much advantage is lost... but it is.

Posted by: McMark Nov 2 2004, 08:33 PM

Worst case scenario would be that the link is perpendicular to the path of travel. In this case none of the motion of the suspension would be applied to the bar because the link would just rotate.

Best case scenario would be that the link is parallel to the path of travel. In this case all motion of the suspension would be transmitted to the bar with no rotation of the link.

Anything in between is a compromise. This may be splitting hairs. I couldn't tell you where the drop off in effectiveness is. It could be perfectly fine until you get to 80 degrees out of sync with the direction of travel. In which case this is all pointless. But I'd bet it's a direct correlation and the closer you are to parallel, the better because less of your action is spent rotating the link.

If you're using a bar, none of this matters, you just use what you got and make it work. If you're designing a bar you have to think about these sorts of things if you want to make The Best ™.

Posted by: trekkor Nov 2 2004, 08:47 PM

I did not intend to create a storm on our calm sea. huh.gif

All I can say is that Britain has set his bar in a position that is softer compared to mine.

He has demonstrated a way to adjust the "unadjustable" rear bar...Brilliant!

Unlike the SRP front bar with infinate adjustment.

KT

Posted by: Ira Ramin Nov 2 2004, 09:58 PM

Interesting theories presented here. The design goal will be to have the swaybar arm and trailing arm close to being parallel to each other, and the drop links perpendicular to them. It doesn’t need to be perfect, but will help provide the most efficient design and minimize additional component loading.

Thanks for all the pictures, comments, and offers to help!! I’d like to work out some kind of initial release at a discounted rate on the first run. Brad would get his discount on the discount. It will kind of be a big test group. I wont promote the bars to my other customers until afterwards.

Brad, I’m looking forward to hearing about your e-commerce site. I’m currently working on my own as well, in between Boxter/996 droplinks, 914 swaybars, boxter swaybars, and keeping up with all the daily stuff.

Here’s a picture of what the 914 bar is starting to look like. There’s still LOT of work to do. smash.gif


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Posted by: Aaron Cox Nov 2 2004, 09:59 PM

im down for a test vehicle. got a t bar up front, why not one in the rear

Posted by: Duffster Nov 2 2004, 10:54 PM

Hey Ira...

I just bought your front bar system ...(Don Kravig called you re: my car). My car is pretty well slammed down and the drop links from the stock rear bar are about 30 degrees from vertical at rest. I'm operating on the theory that I can get a lot more compliance and a lot less roll with 165 pound rear springs and a rear bar than going back to 250 pound rear springs with no bar. Andy Ritter likes that feeling of loose fillings I guess laugh.gif but I drive a lot of less than perfect non-track surfaces, and my old fat butt likes a little "give". If I can edge in front of the rest of these miscreants, I'd love to get your rear bar set up (sorry AAron...) when its ready... driving.gif

Posted by: trekkor Feb 6 2005, 09:38 PM

It's been a while...Why are we still waiting? lol2.gif

KT

Posted by: McMark Feb 6 2005, 10:59 PM

I wouldn't expect anything until next year. confused24.gif

Posted by: Ira Ramin Feb 7 2005, 09:57 AM

“Next Year” ??

It’s coming along slowly, but not that slowly. It’s actually almost ready for testing and was on display yesterday at the Euro/Dunkel swap event. Just received the last of the NC machine parts on Friday. I still need to finish the softer bar (this week) that we’ll be testing, but it will be going onto the test car (thanks Mark G.) in two weeks. We’ll be testing at the next PCA event at the end of next month, but hopefully we can find an SCCA slalom or at least an empty parking lot for some pretesting. I’ll post some pictures later on tonight.

Ira

Posted by: nine14cats Feb 7 2005, 02:18 PM

Hi Ira,

Did Brad Roberts talk with you about using my new race car as a test bed for the rear bar? Late last year he said he spoke to you about it.


914-6 3.6 liter 993 motor
Semi-Tube Frame
Raised suspension points
Slicks all around
etc....

I've been curious as the frame is close to painting....I want all of the welding done soon.

Let me know. Thanks.

Bill P.



Posted by: Ira Ramin Feb 7 2005, 10:40 PM

Hi Bill,
Thanks for your offer to help out with testing. I haven’t talked to Brad about it much lately, except that he did mention that he would have a car to do some testing with. I built two sets of prototypes and will be testing the first one on a local San Diego car. After some initial testing here, the other set will probably go on one of Brad’s customer cars so that he could be involved with the testing. Please tell me a little more about your car, springs, shocks, wheel size, ect. There’re a few guys that have offered to help with testing so far. If Brad still wants to be involved, I’m probably going to leave it up to him to decide who would be the best candidate.

BTW where is Brad these days? I haven’t heard much from him lately. Is he still stuck in the snow somewhere?

Here’s a picture of what it looks like so far. I still need to finish a softer bar and build some backing plates for mounting to the bottom of the trunk.

Ira



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Posted by: Ira Ramin Feb 7 2005, 10:43 PM

This view is a mock up that kind of shows where it will be mounted.


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Posted by: Aaron Cox Feb 7 2005, 10:53 PM

how do you keep it from bottoming on the trunk floor? idea.gif

Posted by: Ira Ramin Feb 7 2005, 11:03 PM

I have a few different sized drop links to try out. I’ll use the longest one that is a safe distance from the trunk floor. The one in the mock up view looks very close to the floor, but it’s actually a bit shorter than the Weltmeister version, so it may be ok. If not, I have a shorter one.

Posted by: Aaron Cox Feb 7 2005, 11:05 PM

QUOTE (Ira Ramin @ Feb 7 2005, 10:03 PM)
I have a few different sized drop links to try out. I’ll use the longest one that is a safe distance from the trunk floor. The one in the mock up view looks very close to the floor, but it’s actually a bit shorter than the Weltmeister version, so it may be ok. If not, I have a shorter one.

good idea. wink.gif

Posted by: Brad Roberts Feb 12 2005, 08:50 PM

Ira,

Bills car has the entire rear trunk floor cut out of it. This will make for GREAT viewing of a new rear sway bar setup. The tub is being powder coated soon, so if you have the billet rear pivot blocks done.. send them to me so we can weld some brackets to the rear frame section to hold them. Give the distance they need to be apart.

Send them here:

Yeaman Autobody
2025 East Bayshore road
Palo Alto, Ca. 94303

I have to have custom rear shock bolts made to hold the race shocks we are running.. I'll need to know what size heim joint you plan to run on the drop links.

B

Posted by: trekkor Feb 12 2005, 09:01 PM

This is gonna be cool cool.gif

More parts... dry.gif

KT

Posted by: Ira Ramin Feb 15 2005, 01:35 AM

Brad,
I’m using 10mm rod ends for my drop links. They will be positioned .8” from the edge of a Koni shock lower mounting bushing. See my shock bolt below.

I’d like to send you the entire assembly so that you can set it up in the correct position more easily. I’ll have it ready to send to you within the next couple of days. It will include a mocked up bar with shaft collars installed to locate the bearing blocks. All you’ll need to do is position it relative to the rest of the suspension.

Ira


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Posted by: Racer Chris Feb 15 2005, 06:04 AM

I don't think I like that arrangement at all.
With the weltmeister and the stock bars at least the arms are long enough so the rear wheels will droop a bit when the car is lifted up.
Because the bar comes from the opposite direction as the trailing arm the torsion bar will cause binding of the rear suspension whenever the droop straightens out the drop link, which will happen easily since the arm and drop link are so short. You will have AX guys coming in from their runs with the car cocked to one side.
Another thing, if someone is using stock type springs on Bilsteins with the car heavily lowered the drop links will interfere with the spring perches unless the drop links come up from below. Doing this was discussed earlier in the thread.

Posted by: nine14cats Feb 15 2005, 07:52 AM

Hi Ira and Brad,

Thanks for arranging my car to be a test vehicle....what we learn we can apply to all the members on the board...

Brad and Scott are building one of the nicest race cars in the 914 community for Doris and I. It's hard sitting in the pits while the season starts, but the wait will be well worth it once the car is up and running and dialed in.

Thanks guys!

Bill P.

Posted by: Ira Ramin Feb 15 2005, 10:20 AM

Chris,
Thanks for your comments. These are very good points and are also my biggest concerns with the design. I moved the bar forward because it significantly simplified the arm design. It was difficult to design a machined arm to clear the sheet metal rib on the bottom of the trunk. The arms are shorter but the drop links should be slightly longer than the Welt design. They connect to the upper edge of the arms which makes them the highest point and allows their length to be maximized. My hope was that this would help make up for the shorter arms.

I designed the bars around a car with Koni shocks and aftermarket springs. The drop links are spaced far enough away from the shock to clear that setup and I thought it would clear the stock spring setup, but I’ll double check. I may have access to some KYB shocks to check this out with. Do you think that it would be similar as far as clearing is concerned? If needed, I can make the bar shorter and space the links farther away.

Brad,
Since I haven’t even mounted the prototype yet, it’s a little premature to put it on a car like Bill’s. I would hate to see you need to make changes to Bill’s beautifully powder coated frame to fix binding or spring interference problems. If you have the complete rear suspension on it, you can fully check it out before welding in mounting brackets. That was part of the reason for me sending the complete swaybar assembly. If needed, we can probably build longer drop links for his car to address any binding problems. Clearance between the drop links and spring hats will need to be checked.

Thanks,
Ira

Posted by: trekkor Feb 15 2005, 10:35 AM

I'll be on the a/x track in 3 weeks. I wanna help! boldblue.gif

Does the new rear bar mount in the stock bushings or do you need to do an all new install?

KT


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Posted by: Cloudbuster Feb 15 2005, 11:01 AM

QUOTE (trekkor @ Feb 15 2005, 08:35 AM)
Does the new rear bar mount in the stock bushings or do you need to do a all new install?

It looks like it would need new mount points. This is because a hollow bar would have to be straight and it can't snake around the tranny mounts like the solid bars do.

Posted by: SirAndy Feb 15 2005, 11:59 AM

QUOTE (Ira Ramin @ Feb 15 2005, 08:20 AM)
These are very good points and are also my biggest concerns with the design.

i've said this before, i for one wouldn't hesitate to install a version that mounts like on the factory GT's.
bar inside the trunk, droplinks down through the trunk floor. not bottom out, droplinks hitting anything ...

idea.gif Andy

i hope glenn doesn't mind posting this ...



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Posted by: Brad Roberts Feb 15 2005, 01:16 PM

Send it to me. I'll mock it up and see what we have.

Notice in the GT pic that sway bar doesnt pick-up at the rear shock mount. It has to be mounted to some place on the control arm forward of the axle. I promise travel is limited on this setup.

I have Randal Barricks really clean 914 that we can test with also (stock tub on slicks)


B

Posted by: SirAndy Feb 15 2005, 01:27 PM

QUOTE (Brad Roberts @ Feb 15 2005, 11:16 AM)
Notice in the GT pic that sway bar doesnt pick-up at the rear shock mount. It has to be mounted to some place on the control arm forward of the axle. I promise travel is limited on this setup.

i would have to disagree with that assesment. look at the GT pic closely, then look at trekkor's under body shot.

you can see that the GT droplinks come down right where the stock droplinks mount.
i think all they did was making longer droplinks ...

cool.gif Andy

Posted by: Aaron Cox Feb 15 2005, 01:32 PM

QUOTE (SirAndy @ Feb 15 2005, 12:27 PM)
QUOTE (Brad Roberts @ Feb 15 2005, 11:16 AM)
Notice in the GT pic that sway bar doesnt pick-up at the rear shock mount. It has to be mounted to some place on the control arm forward of the axle. I promise travel is limited on this setup.

i would have to disagree with that assesment. look at the GT pic closely, then look at trekkor's under body shot.

you can see that the GT droplinks come down right where the stock droplinks mount.
i think all they did was making longer droplinks ...

cool.gif Andy

i agree....mounted in the exact same place....just on top of the sheet metal... huh.gif

Posted by: McMark Feb 15 2005, 01:38 PM

Looks like a stock bar mounted on top. confused24.gif

Posted by: SirAndy Feb 15 2005, 06:20 PM

QUOTE (McMark @ Feb 15 2005, 11:38 AM)
Looks like a stock bar mounted on top. confused24.gif

yepp, stock bar in the stock mounting location, just on the other side of the floor sheetmetal.

cool.gif Andy

Posted by: Aaron Cox Feb 15 2005, 07:02 PM

QUOTE (SirAndy @ Feb 15 2005, 05:20 PM)
QUOTE (McMark @ Feb 15 2005, 11:38 AM)
Looks like a stock bar mounted on top.  :confused:

yepp, stock bar in the stock mounting location, just on the other side of the floor sheetmetal.

cool.gif Andy

why did they do it?

my guess is to keep the bar from bottoming on the trunk floor... conventional wisdom would say that thet used the same length droplinks..... unsure.gif bar wont bind into the floor..

Posted by: Racer Chris Feb 15 2005, 10:08 PM

Ira,
Here is a picture of my car with the Weltmeister bar installed and my custom drop link arrangement. This worked out very well by the way.
When I had stock type 180lb springs the lower perch was located at the lowest adjustment groove on the shock. If the drop link was above the shock attachment point it would interfere with the spring perch.
When I had the bar set a bit stiffer it interfered less but I sometimes ran into problems on the race track with the unloaded side binding up in a corner, which totally ruined the handling for the rest of the session. The reason it bound up is that the drop link would extend horizontally in line with the sway bar arm as the inside trailing arm drooped and would not return to the correct position after exiting the corner.
I guess a chain to prevent the trailing arm from dropping too far would eliminate the possibility of this happening but there is another issue. If the trailing arms are restricted from extending downward when the car is raised it becomes difficult to remove/install the wheels. There is a delicate balance somewhere in all this, and I would rather see you build the best possible system without investing in a lot of parts that become unsuitable for sale first.


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Posted by: Ira Ramin Feb 17 2005, 01:06 AM

Trekkor,
The bar mounts in a different position, about 3” forward. I figured that was no big deal since most cars don’t have factory brackets anyways. Thanks for offering to help with testing. I wish that I had built three sets, but I only built two and they’re already spoken for. I’ll definitely keep you in mind if things don’t work out with them, or for the next batch.

Andy,
I will probably be doing a version that could be mounted in the trunk. It may only consist of changing to a longer drop link, possibly the one that I use on the front swaybar. Keep in mind that it will need more than just a hole in the floor for the drop link. It will need a long slot to allow for the adjustment. Hopefully I will end up with a design that will work good without needing to be mounted in the trunk.

Brad,
The bar is on its way to the shop for Bill’s car.

Chris,
What do you think about mounting the bar below the transmission and connecting the drop link the way you did? It would probably solve the possible binding and clearance issues, and the geometry might be a little better than your current setup. It would be similar to my rear 911 design. Figuring out what to mount the bearing blocks to would be a little bit of a challenge.

Ira

Posted by: Travis Neff Feb 17 2005, 04:56 PM

Since the dogbone/tranny mount seems to be a bit of an obstacle, what if you reverse positioned the bar, not upside down - but turn it around.

Something like this: obviously the pillow blocks would need to be further inward due to the rear shock mount cutouts, hell it is an idea...


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Posted by: Travis Neff Feb 17 2005, 04:58 PM

Also, since the bars up an down movement is in unisyn (sort of) with the shock and control arm, I don't know how there would be an interference with the rear shocks. As long as there is X amount of room away from them, that X should always stay the same, no?

Posted by: Ira Ramin Feb 18 2005, 12:51 AM

Travis,
Your sketch has the best geometry of any of the designs but I think that the engine or the starter may be in the way. I think we considered mounting that way, but it’s definitely worth taking another look. We’ll be installing the prototype on Saturday morning and will try to take a fresh look at the other possibilities.

I see what you’re saying about clearing the shocks, it makes sense.

Ira

Posted by: Racer Chris Feb 18 2005, 05:49 AM

If you made long mounting blocks to position the bar beneath the tranny (at the back) you still have exhaust interference issues to deal with (except with the Tangerine header), as well as worker access issues. sad.gif

Posted by: Travis Neff Feb 18 2005, 09:50 AM

Should be no problems with engine interference, but I didn't think about the starter. that'll be a tight fit.

Or you could do a through body one (like the front) but have it in the trunk going through the walls of the rear strut mounts, obviously you would need longer and doglegged arms for clearance.

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