908-3 Sti.

B85 · **Posted:** Sun Dec 02, 2012 1:24 pm

Been away from this chassis for some time but back at it now.

She is a mid engine being built to look like the Porsche 908-3.

I'm using the motor and trans from a 1995 JDM Sti. Have installed the spool and rear cover plate and am working on the shifter,and other things. :BH:

Wheel base is 96" x 68",Rim's are 8" f and 12" r Tires are 205/50/15 and 295/50/15.
Looking for 320HP ++ from the 2.0L turbo.Was something like 265HP stock .Thinking of going water to air cooling? Need some weight to help balance the car?

Working out the rear axle setup now ,the front end was done,some time ago. My bad! Like 5 years ago. Thinking I will use the front spindle system from the car? This would keep me from needing a custom axle? No parking brake but I could go line lock for that? Think this will speed thing up. I have the rear spindles on my other Lotus11/15 in the rear and she need a custom axle. And she needs to be finished also. My Bad! :oops:

Looking for input on the shifter system. Anyone working on this?

So off I go again. Randy

Off Road SHO · **Posted:** Sun Dec 02, 2012 1:55 pm

Randy,

Jim Cunningham from the old buggy shop, Brandwood Cars on University, builds a cable shifter setup for a lot of mid engined cars. He now works out of his huge shop in Apache Junction. Don't have his number off hand. His specialty was mid engined buggys.

Tom

KB58 · **Posted:** Sun Dec 02, 2012 2:45 pm

Wow... for a second I thought that was you in your car. Whew, wouldn't want to see someone complete such a nice car in such short order... makes the rest of us look bad.

egoman · **Posted:** Sun Dec 02, 2012 2:45 pm

I notice from looking at the pics that you will have the option of moving the driver position back several inches. Quite honestly the car in the photo looks like the driver is in a compromising position: ie. legs ahead of axle centerline and quite high up. Are these changes you are looking into for your design?. How hard was the install of the trans parts to convert the transaxle? This is gonna be great!

B85 · **Posted:** Sun Dec 02, 2012 6:27 pm

KB58 wrote:

Wow... for a second I thought that was you in your car. Whew, wouldn't want to see someone complete such a nice car in such short order... makes the rest of us look bad.

I've got your book around here some where????

Checked out your build ,looking GOOD!

Thanks Tom. I spent the day looking for my old shifter he built for me??? My BAD! Was hopping it would work for the Subaru trans? Headed back out to the shop to look some more.

Egoman, I'm going to be putting my feet about even with the front rim's. And yes in the 908-3 the drivers feet were about 9" in front of the wheels.

B85 · **Posted:** Sun Dec 02, 2012 7:39 pm

Not bad!!! :roll:

7 hours and now its found. Now to see if it will work with the 5-speed??? :shock:

B85 · **Posted:** Sun Dec 02, 2012 7:53 pm

Here is a shot of the 908-3 pedal box.

Off Road SHO · **Posted:** Sun Dec 02, 2012 8:01 pm

Wowser. Looking good.

Didn't I meet you at your place of business about 3 or 4 years ago?

Tom

B85 · **Posted:** Sun Dec 02, 2012 8:23 pm

Think so Tom. Drove out to the house to see one of the cars that I have still have not finished? :roll:

Think it was the 7 with the 5.0 ?
Randy

egoman · **Posted:** Sun Dec 02, 2012 10:45 pm

Yes that pic shows your feet about a foot ahead of the centerline. Most sanctioning bodies wont let that even race any more.
Thats why the first thing I noticed was how much more rearward you can place the driver with the suby drivetrain.

cheapracer · **Joined:** Wed Nov 12, 2008 6:29 am **Posts:** 2613

Amusing when a kit car or home built has bird-poo welds everyone is up in arms but when it's a Porsche .....

Kartracer47 · **Posted:** Mon Dec 03, 2012 2:52 pm

It is also an aluminum frame.

OptimusGlen · **Posted:** Mon Dec 03, 2012 4:23 pm

cheapracer wrote:

Amusing when a kit car or home built has bird-poo welds everyone is up in arms but when it's a Porsche .....

From another forum I'm on.

Quote:

the 917K and varients used a stressed aluminum alloy tubular space frame

AluSwiss consulted on alloy selection and method of joining tube ends

in order to more widely distribute frame loading (stressing) and to preserve al alloy strengthening treatment, a lower temp inert gas welding technique combined with eutectic alloy filler was employed, resulting in rather large and irregular weld fillets/lines

additionally a CibaGigy epoxy based sealant was applied over all weld areas @ tubing ends to eliminate weld porosity

as you may recall the entire finished frame structure formed a single "air chamber" charged with compressed dry nitrogen before each track outing

chief mechanic and/or porsche factory engineer would monitor gas pressure - any pressure drop would indicate micro fatigue fractures/ reduced structural integrity of aluminum alloy space frame

this space frame was capable of absorbing minor shunts without gas leakage occuring

the welds in fact are very special and have a unique appearance

the first time FIA Inspectors viewed the (917K) space frames, they were invited to a late afternoon lunch and a lengthy conversation unfolded (prior to homologation approval)

B85 · **Posted:** Mon Dec 03, 2012 9:35 pm

Did you know the welds are GAS!!!!

Worked on the rear uprights.

Here are some questions for some of you Formula guys.
What camber do you run in the rear?
Any caster?
Does your system have camber gain in bump?
How much toe in/out?

On to the upright,should I add a Spacer where the green tape is ?
Well maybe put a spacer up to the steering arm
The bottom 1"x2" x 11" will have outer pickup points for a wish bone.
In the center is a turned 2 1/2" x 1 1/2" mount for the old ball joint socket. The socket is like 1.492 x1". So that is what I turned the last 1" to. It has a nouch cut into for the bolt system.
The strut mount will get a adaptor to a ball joint.
Their will be trailing arms that will go to pickup points on the chassis.

Anybody know if the JDM Sti's had LSD in them stock? Front diff.

Also,the front will have non-vented brakes and the rear will have vented "BIG" brakes. Going to use a blance brake system and can size the masters to what will be needed. Big brakes in the rear ? BAD?

So, what do you think? And thanks for the help.
Randy.

Randy

cheapracer · **Joined:** Wed Nov 12, 2008 6:29 am **Posts:** 2613

B85 wrote:

Did you know the welds are GAS!!!!

How many pictures of "GAS!!!!!!!!!!!!!!!" welds would you like me to post?

Rickman for example made their reputation partly on their GAS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! welding from the early 60's.

But it wasn't the point, I was comparing the reactions to a homebuilt's Vs a Porsche - point was missed.

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908-3 Sti.

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