suspension

Dan944t · 12-11-2000, 08:20 AM

I have a 1987 944 Turbo that unfortunetly doesn't have the M030 sport option. I would like to upgrade the the springs and wheels for local club racing. I have decided on ATP 17"x7.5 fronts and 17"x8.5 rears, but I have no clue on what spring i should run? Any suggustions would be great. I want a street/race spring. Thanks
Dan

wolfrpi · 12-11-2000, 12:57 PM

I think that your choice on spring rates depends on your ability to put up with a harsh ride. With that said, my 944 with 275lb springs (with adjustable ride height) in the front rides very well on smooth California roads. I think Paragon Products reccomends a maximum rate of 250lb without changing the rear torsion bars. I'm currently replacing my bars with 28mmm so I have yet to see how the ride is effected. In addition I would seriously consider upgrading the shocks if you have not done so already. My suggestion would be to go with Koni sport yellows all around. Total cost without the rear bars should be about $1000.

Best of Luck,

Erick

todd951 · 12-11-2000, 02:32 PM

I've got Bilstein coil-overs with 350# springs in the front, and 30mm torsion bars in the rear with Bilstein shocks. Surprisingly, it doesn't seem very much harsher than the stock suspension with the original Koni sport shocks, although it is definitely harsher than your average four-door sedan. Again, it's a matter of how harsh a ride you're willing to tolerate. I think my car is just fine, but that's just my opinion.

Dan944t · 12-11-2000, 05:17 PM

I thought a 951 that wasen't equiped with konis could never be because of the Aarm layout? Anyways I really don't have the money to sink in another grand in suspension when i just did that in wheels and tires. Would it be beneficial to run stock shocks with harder springs? I can tolarate a hard ride but I still want my suspension to absorb some of the bumps. I would also like to lower the car about an inch. Would i have to buy both front and rear springs if I wanted to lower it an inch? Basically I just want to tweek out as much performance with just wheels tires and springs for the best all round street/track car. I want the car to be more tighter in the turns and handle better.

Thanks
dan

wolfrpi · 12-11-2000, 05:53 PM

Check out automotion...here's the link...it looks like you'll end up spending about $180 for 250lb springs for the front if that is all you want to do. The springs will lower the car about 1.5? inches. To lower the rear, adjust the eccentrics on the rear trailing arms.
http://www.***************/am/page_listings2.asp?c=23100&p=31755

diannone · 12-11-2000, 07:07 PM

less 20% for pca members

mike944 · 12-11-2000, 08:14 PM

Dan,

If you use stiffer springs with the stock shocks, just be aware that the shocks won't last as long. Without getting into a long explanation, a heavier spring can store more energy, and needs a stronger shock to absorb it all.

as WOLFRPI said, the rears are adjustable. If you don't have enough range in the excentric adjuster, you can dissassemble the rear torsion bar assembly, and remove, and rotate the torsion bar. Porsche has a clever differential spline design on the rear torsion bars. if you remove the bars, you'll notice that one end has 1 fewer splines than the other end. ( i think one has 31, and one has 32) using those numbers for example: if you rotate 1 end by one spline
(360/32=11.25 deg)
and rotate the other end by 1 spline
(360/31=11.6129 deg)
you are left with the difference between the 2, which is .3629 deg. By using the rear susp. geometry, each 1 deg. move will move the wheel approx .3" therefore a 1 spline difference will move the wheel approx. .1"

this conbined with the excentric adjuster gives you a very fine adjustment with which to tune the rear suspension. it's too bad they didn't do something as clever on the front end.

I hope i didn't make it too confusing.

one question i have for people who replaced front springs without doing any other mods, does the car push (understeer) more now? i would think it would. when you make one end of the car stiffer, the other end will bite more, and the end with the new parts will slide more.

Dan944t · 12-11-2000, 08:28 PM

Thanks for all the information it is helping me out greatly. Paragon Products has weltmesiter springs 250# for $114 a pair plus $10 shipping. Basically I will just have to save up and purchase konis. I really want sport shocks that are adjustable but i just dont have the funds right now with school and my recent wheel tire purchase. However maybe next year. Do you think I can get by on this setup until next year? I think I have standard boge shocks(there black) and I would like to run the 250# spring in them. I think I will have a local shop install my springs as I dont have a compressor or anything like that. About how much am I looking at to have a install the springs?

Thanks
Dan

mike944 · 12-11-2000, 08:47 PM

your shocks should last fine, unless they are marginal already.

I want to do some suspension work this winter, but having an old house with oil heat, isn't going to leave me much play money. I would love to be able to do front springs, koni adjustables front and rear, a stiffer rear sway bar, and polygraphite bushings. but i can't do it all at once, and i'm afraid i'll throw off the handling too much if i piecemeal it. i'll just have to save up, and do the entire thing next summer.

Sorry i don't know how much it'll cost to have springs installed, i hardly ever pay someone else to fix my car. I don't trust anyone else to fix my car and not screw something up in the process.

Mike