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T-Bar Swap on Snailshell Tranny

 
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Rasta Monsta  



Joined: 12 Jul 2006
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PostPosted: Fri Apr 18, 2008 4:02 am    Post subject: T-Bar Swap on Snailshell Tranny Reply with quote

OK, so I found a couple of comprehensive write-ups* for swapping t-bars on a 944, but I also know that the snail has a different 'relationship' with the t-bar carrier than the Audi box.

Anyone who has done this, can you briefly summarize the differences in the procedure?

TIA


rasta

*Clark's Garage & Kevin Gross FAQ.
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924RACR  



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PostPosted: Fri Apr 18, 2008 6:53 am    Post subject: Reply with quote

I haven't done it exactly, but since the trans is mounted to the t-bar carrier, seems like you'll have a different prospect getting the rear suspension out. Ideal might be keeping the trans in place, after unbolting it from the t-bar carrier, perhaps with good jack stands, while you lower the rear suspension out.
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ideola  



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PostPosted: Fri Apr 18, 2008 12:32 pm    Post subject: Reply with quote

Rasta
I have a set of the 30mm T-bars you're after which will be going into my snailshell / LSD equipped UWB...so we can learn together on this one...
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Paul  



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PostPosted: Fri Apr 18, 2008 1:01 pm    Post subject: Reply with quote

924RACR wrote:
I haven't done it exactly, but since the trans is mounted to the t-bar carrier, seems like you'll have a different prospect getting the rear suspension out. Ideal might be keeping the trans in place, after unbolting it from the t-bar carrier, perhaps with good jack stands, while you lower the rear suspension out.


That can be done, or a couple of concrete blocks with a foot long 2 x 6 on top of the blocks. Do this centered on the differential. You will have to remove the rear section of the exhaust.

Once the rear suspension is out, its easy to check the shift linkage, etc.
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ideola  



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PostPosted: Fri Apr 18, 2008 1:16 pm    Post subject: Reply with quote

In my case, everything is already out of the car...exhaust, torque tube, tranny, suspension, everything. I'm putting 30mm t-bars into a snail shell torsion carrier, and then will be adding on refurbed / race-prepped 944 alu trailing arms, etc. My question is how do I properly index the new setup. I'll have a complete snail shell 5-lug rear suspension assembly available to compare with...can I use that as a reference for proper indexing, or is there a better / easier way?
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Rasta Monsta  



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PostPosted: Fri Apr 18, 2008 3:20 pm    Post subject: Reply with quote

Dan, check the links in the first post.
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morghen  



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PostPosted: Fri Apr 18, 2008 3:33 pm    Post subject: Reply with quote

like i said...i'd recomand taking the gearbox out and anchoring the torgue tube because once you got the carrier down...you probably will find it not so easy to fit it back up if you dont lower the elevator. I used an elevator to raise the car...take the carrier out and when it was fit back time i just placed the t-bar carrier on wooden blocks and lowered the car on it.
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924RACR  



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PostPosted: Fri Apr 18, 2008 9:47 pm    Post subject: Reply with quote

Dan - what ride height do you want on the thing?!?

Most important thing when swapping torsion bars is to make sure the two sides end up LEVEL. Center the height adjustment in the spring plates before setting the indexing of the t-bars, too - otherwise you could easily find yourself with the two at opposite ends and no chance to fine-tune height without again reindexing.

Expect to need to do the install twice. Sorry. It's just that hard, when you're changing to a completely different bar size.

Note that if you put the spring plates (with 30mm bars installed) at the same unloaded angle as the spring plates, unloaded, with stock 23.5mm bars installed... the car's gonna look like a dune buggy, the ass end's gonna be so high in the air! So you have to drop them down considerably.

Dan, what's your schedule like for this install? 'Cause I've got to get over to Chris's and dial in his new rear suspension, probably happen on Sunday, might be a good time to meet up, whether it's just to compare/take measurements on his car and/or check out your rear axle. At least I'll be over that side of town.

Our cars are set to a ride height of about 5" (to the rockers), maybe 5.25" in the back... you'll need to decide if you want the UWB car that low or not... probably not - makes jacking a real PITA. I'm guessing 6" might be as low as you'd want to go with a street car, think that's where I'm going to target for my 931 (when I do the suspension).
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ideola  



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PostPosted: Fri Apr 18, 2008 10:03 pm    Post subject: Reply with quote

Vaughan
I'm not in a huge hurry to get this installed, but I've been disassembling the 944 suspensions that I have, and I'm planning to get the 5-lug suspension out of one of my donor 931's very soon, hopefully this weekend. So I've been thinking a lot about suspension recently Before I tear that 931 5-lug suspension apart, would it make sense to keep it intact so we have a point of reference?

Regarding the ride height, I would like a good balance between street & track. While the car will be streetable, it probably won't see that much pure street driving (i.e., won't be planning to drive it to Hershey or anything like that). So I would say probably 5" would be the lowest I'd want to go, but probably lower than stock. The 941 was lowered quite a bit by the PO, so I know what you mean about being a PITA to jack up!

You know the front spring / strut set up I have, so I'll definitely be needing your input on how to set it up properly As for Sunday, where will you be, Brighton or Livonia? I might be able to make it later in the afternoon...
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924RACR  



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PostPosted: Fri Apr 18, 2008 10:15 pm    Post subject: Reply with quote

Sunday would be in Livonia, at Chris's shop. You were there once before, when we were installing the MSD in his car.

Those front struts will be set up for about a 5.5" ride height.

I don't think the stock/spare suspension provides much of a reference point - the 30mm bars are something like 4x as stiff as stock.
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ideola  



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PostPosted: Fri Apr 18, 2008 10:37 pm    Post subject: Reply with quote

5.5" will probably be just fine.

What time will you be at Chris's shop? Livonia is a lot closer, so I can probably come on over.
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Rasta Monsta  



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PostPosted: Sat Apr 19, 2008 12:50 am    Post subject: Reply with quote

<==jealous

. . .you guys are lucky to have one another's help.

As to ride height setting, etc, if you read the links I posted above, they use math, trig, etc to provide an educated starting point for the indexing nightmare, including a calculation which takes stiffness into account.
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924RACR  



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PostPosted: Sat Apr 19, 2008 7:53 am    Post subject: Reply with quote

LOL... well, dude, my wife does love the scenics of the Pac NW, so all's you gotta do is fly us in for a long race weekend, and yer covered... race setup, crew, AND catering!

Dan - Brighton is Steve P.'s shop, not Chris's... time at Chris's is TBD, but we'll need to make a plan... OTOH, we usually aim for 10AM, so sometime after that would be wise... best bet is to call me on my cell...
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fiat22turbo  



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PostPosted: Fri May 02, 2008 7:29 am    Post subject: Reply with quote

I'd like to look into this as well. So Rasta you can either come over to my garage and help me screw up my car, er fix up my car or we can screw yours up first. Either way, there is local help available. Just wish I was more experienced in the ways of the 924.
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924RACR  



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PostPosted: Fri May 02, 2008 11:04 pm    Post subject: Reply with quote

We did end up re-working Chris's suspension completely, due to a mismatch of spring plates from swapping back to steel trailing arms from the alloy arms... but Dan ended up busy (work interfered), so no chance for him to attend and learn.

But we are going to make a plan to tackle his suspension before long, so we'll keep you posted...
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