V2Rocket

Would you have any concern with running a 400 or less rated spring on a street car, without torsion bars? I recall that on a 944 the effective spring rate is like half of the actual rate based on the positioning of the pivot point, so I was thinking like 350 or 375s to match with my 200# fronts...

catamax944

I dont see why rubber bushings would be a problem on a street car with torsion bar delete , a race car is a whole diffrent story. The torsion bar delete setup is very similar to the 964 rear suspension setup and it works fine with rubber bushings.Why would on the 944 be any different ?

MAGK944

That would work fine as long as you don't venture to anything more aggressive, look at it this way:

Stock F = 140lb ish = 130 effective
Stock R = 23.5 TB = 126 effective

Now move to a typical upgraded street car:

F = 200lb = 180 effective
R = 25.5 TB = 175 effective

If you remove the 25.5 TB you will need a 300-325lb coilover spring to achieve the same F&R balance. This set-up should handle that rate quite well.

Now, if you want a more aggressive street set-up, say 350 F, you are looking at very high (500lb+) rear springs. The main problem with that sort of rate on this set-up is the rubber bushes. The rubber "squishes" and deforms way before the damper valving has time to do it's job. Maybe some Delrin bushes would be a cheap alternative to sphericals, but something other than rubber is needed.

V2Rocket

Fine by me...

...with the build quality of southern California roads, 200# is plenty stiff

Justin S2

I wish Bilstein would get their act together and make front struts for the later cars (87+.) I recently went with a Koni setup but if Bilstein had matching front and rear pairs for my s2, I would have the correct shocks to do this conversion. Anyways, It was a nice read and good job Robstah!

Justin S2

Nice choice! I hope to own a Z3 M Coupe after I graduate. Probably an S52, as the S54 seems to be more expensive for parts.

Crackership

Did you have to re-index the t-bars in order to lower the car with these? I know there's some height adjustment in the factory suspension, but not a lot. I would assume that the primary motivation for this setup would be improving the ride/performance of the suspension more than gaining height adjustment, but it would seem that you'd wind up with coilovers that weren't really adjustable.

Please, correct me if I'm wrong. I'm just trying to apply what I learned from the coilovers I installed on my Alfa. That has t-bars in the front and you have to re-index them a bit in order to gain adjust-ability when you add the coilovers. Obviously, that's a totally different suspension, just wondering how you approached it. Regardless, it's an awesome setup, and I very well may have to get myself a set. I hate how hard the car squats on acceleration.

This is the front RS Racing coilover for the GTV6... it's a touch more expensive than most 944 coilovers I've priced, but it does work well

Crackership

Honestly, I'm not really looking to lower my car much at all... I rather enjoy being able to drive over speed bumps and such. Plus, it rains so much around here that the entrance to every parking lot is crowned heavily, so they can be quite difficult to get in and out of in a low car. I was just wondering if there was much height adjustment available without re-indexing.

I'm pretty sure I'll be giving this a shot in the near future. I've been wanting to add something to the rear for a while now, but this is the first reasonably affordable option I've found.

On a related note, how do you like the Bilsteins on the 944? I had them on my GTV6 before the RSR suspension, and I really liked their compression, but I thought the rebound was a little too fast. They may have just not been well matched to the spring rates. I don't know. Wither way, I honestly think I would drive my GTV6 more if it still had the Bilsteins on it though, the RSR suspension performs amazingly well... it also excels at knocking out teeth and rupturing spleens...

Basically what I want to do with the 951 is get rid of the squat on accel, the dive on decel, and the ducking and weaving it does in the corners, but still be able to comfortably drive it daily and not need a chiropractor any more than I already do... You think your setup would accomplish that?

Thanks!

PHert

Have you guys heard or figured out a solution for the early 944 steel arm?

car_slave

Very cool! I wonder if the Konis come apart the same way, they already have a lip for the spring perch. Anyone ever take a Koni apart? I guess you'd have to cut away the dust shield before you get any grip on the shaft.

jharding

Yes, early 944 steel arm has been figured out. I assume you are talking rear suspension. I have the coil-over kits, springs, and an entire torsion bar delete rear carrier that will fit an early 944. Or you can get just the early shock coil-over kits from me and buy lower spring rate springs to use with your current torsion bars. Although I don't know what the advantage of keeping your torsion bars is, as you'll still only get to lower as far as the eccentric will let you without re-indexing the torsion bars.

But, back to the program. PM me if interested in the coil-overs and/or torsion carrier. I used that set up for years in DE. The car handled great.

McMikey

I was wondering how hard of a job it was and about how long did it take?

Thanks!!

Butters944

Bumping this AWESOME write up

I'm a little confused reading some of these posts? This write up, is it for any 944 or just early/late? And am I correct that in my understanding, if your torsion bar spring plate is adjusted as low as possible, the coil over won't be able to lower the car without reindexing or deleting?

Last question. What rear spring rate (torsion bar delete) would be equivalent to stock torsion bar stiffness?

veleno

Great idea!

Like above, is this for an early or late setup, maybe both with some adjustments?

MAGK944

Moving the spring plate doesn't adjust the rate of the torsion bar it just raises or lowers the car. The rate of the torsion remains the same throughout. However if you adjust the height with the spring plate the rear coilover will have more or less preload, so you have to wind the lower perch up or down to compensate for the new height.

In reality with a combined tb and coilover system you still have to reindex to adjust height.

The equivalent coilover spring for a stock tb (23.5mm) with tb deleted would be 225lb. This would give you the same effective rate as the stock tb.