Potomac-Greg

Chuck Moreland's three-part writeup available on this site is fantastic. https://rennlist.com/forums/924-931-...-part-1-a.htmlThat doesn't mean it was easy! I just took my time. I had picked up a set of spring plates beforehand and cleaned them, and put on a set of Racer's Edge delrin bushings. So that part of the job was done before the real work started.

I worked a bit Thursday night (put the car on jackstands and pulled off the coilovers to install 600# springs). Friday I started unbolting the torsion tube.

Helpful hint: If you want to use the "tilting" method to remove the torsion bars, you should NOT put your jackstands under the torsion tube. Duh.

I ended up disconnecting the brake lines. With the coilovers out and the trailing arm off the torsion bar, the stress could have hurt my nearly-new ss brake lines. That led to a constant battle with dripping brake fluid.

The toughest job was prying the forward bushing of the aluminum spring plate cover out of it's housing (under/behind the doors). T'was a bitch and I had to walk away a couple of times.

Rather than take off the driver's side half-shaft, I instead took off the exhaust cat-back. Call me crazy, but five conventional bolts on a non-critical piece of equipment seems like a better option than messing with six(?) cheesehead fasteners on a critical driveshaft. I also took the opportunity to clean/paint the exhaust.

It was like birthing a baby cow when those t-bars slid out! The grunting and pulling followed by sheer joy. The tilting trick works, but it is REALLY close. Those mf'ers are heavy. I think I'll keep one under my bed! It was comforting to know that I would not be putting them back in!

The metal surfaces where the bushings were to ride both needed work. The outer surface was ok, and a little dremel sanding wheel did the trick. The inner was was pock-marked with fossilized rubber chunks that felt like enamel paint. I had to use a dremel grinding stone to chew them off. Then sanded for smoothness. I know they were rubber from the smell as they were rubbed off. The outer delrin bushing needed some sanding in order to fit and to allow relatively free motion. There's resistance but not enough to worry about.

Re-assembly was easier, until I stripped my upper shock mount bolts. Yes, both. Luckily I found a local Porsche guy who had two spares. My error? I was bolting on the bottom, and then trying to get it lined up in the top (which is a blind, dark hole). Stupid. The top was very easy to align and bolt FIRST, then the bottom bolt was easily installed.

I got it all done at about 9PM yesterday, and went for a short drive, but quickly discovered that I did not bleed my brake lines well enough, so I had very weak / mushy brakes. I'll have to bleed them tonight. I didn't want to go fast or far with no brakes, so I can't review the suspension at this point.

If anyone wants two spring plates with old rubber bushings, I'm more than happy to "pay it forward." Having that nasty job done in advance was a HUGE advantage.

aben8057

Hi Greg,

This is my next project as I know you were "another" running with TB and coilovers. What was the total weight savings and do you "feel' a difference?

Alex

Potomac-Greg

I would guess that a pair of t-bars weighs about 18 lbs. Of course, you're adding springs that weigh about ten.

I haven't test driven other than slow roll around the 'hood so I can't say.

DANNiE

What is the real point of removing these torsion bars..?

krazykarl

With coilovers it's much easier to adjust ride height and change spring rates then replacing and reindexing torsion bars.

Potomac-Greg

THe torsion bars can do everything the coilovers do, but it's just more complex. To change the ride height and spring rates with t-bars, you need to disassemble the rear suspension and remove the torsion bars, and replace or reset them to get the intended change. So a ride height change can take you 5 hours of sweating (if you suck at it like me) while coilovers let you adjust ride height with far less effort (pull the wheels, twist the spring seats.

So, if you're happy with your ride height and spring rate, there's no reason to go to coilovers. If not, then you either need to get good at t-bar adjustments, or you pull them and replace them with coilovers. It should be noted that if you are your own labor, the cheapest way by far is to change and adjust t-bars. T-bars are amazingly simple and elegant. It's too bad Porsche didn't make them more accessible. They also do not reduce weight or provide more room in the car. I suppose they were a carry-over from the rear engined architecture where the space is more important.

PORSCHE968

I had heard that the T bars transmit more road noise. Let us know if you see a dramatic reduction in highway noise. My 968 really howled once the tires wore past halfway.

roman944

its too bad there are no rear coilovers for the early car

I want to know what you think of the car when you come back from a race day

pormgb

Done mine three weeks ago, I'm using Aldan double adjustable shocks with Racers edge lower shock bolts. To be honest I was going to do a Torsion Bar reindex but I just decided to dump them, I was very concerned about my lower shock mounts so I spent the $150.00, Racer's Edge bolts worked well for me since my Aldan shocks already had 1/4" lower bearings.

What spring combinations are going to use? I currently have 400lb on the rear and 300lb on the front.

Potomac-Greg

I have 450 up front and 600 in the rear. I used to have 250 in the rear in tandem with the t-bars, and all I did was uprate the springs. I have the three-position M030 rear sway bar, but I set it on the softest setting for now.

pormgb

Wow, 450/600 are pretty stiff springs, is car specifically setup for autocross? how does your car feel on bumpy roads?

I find my setup to be very harsh on bumpy roads, I have a Weltmeister adjustable sway bar but I need to dial it in.

Potomac-Greg

It's stiff as hell. It's just a track car (HPDE) and occasional weekend fun. It's in line with what lots of racers use in 944 Cup racing. I've never done autocross, but it would be fun to try.

thirdgenbird

im running 350/450 on the street and will probably pick up a set of 600s so i can switch to 450/600 if need be

ArthurPE

this is an interesting thread...good info

the stock 951 (1986 no M30) rates are as follows?
F 125 lb/in
R 126 lb/in

correct?

I'm thinking a basic Paragon 1 Koni Cup kit and retaining the torsion bars
with 250 front, 250 rear(giving a ~266 effective rate) and the same rate ratio 1/1 as oem...

I would lower the rear using the eccentric ~6 mm or so...
the front would be adjusted for a 10 mm drop
my stock ride ht measured from floor to lip is 25.5 all 4 corners, the front may be +1/8"

the car will do schools, but no competition, and will be a summer/weekend car....
I like the stock ride and doubling the rate makes me a bit nervous, I'd rather be 175/175 or so but can't located such an option

any feedback? thnx

Potomac-Greg

If you want better handling without messing with the ride, the solution is beefy sway bars. You can get "M030" sway bars, which are the stiffest that Porsche sold with the 944, or go big time with Tarett adjustable sways.

PS: I have a pair of 250# x 7 inch x 2.25 ID springs looking for a home if anyone's interested.