Suspension for 1971 911... 21/28?

Micker747 · Micker747's Garage

Hi,

i have almost finished restoring my 1971 coupe with 3,2 and 915 gearbox. Now engine power is adequate, but suspension...

Any good ideas for an ideal setup for comfortable street use, and some track day action?

The car is all original otherwise, with 6X15 Fuchs.

I heard 21/28 with Bilstein clubsport dampers is nice, but i am very open to suggestions.

Have a nice weekend

Mike

Jim Richards · 10-20-2006, 07:31 AM

Mike, I have a 22/29 set-up with Bilstein HD's (front) and Sport's (back). I have a 2.7RS-spec engine. It's OK on the street and good on the track, though I think I can improve things with custom valved shocks. BTW, my sways are 19mm (front) and 15mm (back).

Micker747 · Micker747's Garage

Jim,

Thank you for your fast reply. Nice setup you have there. As it is, i don't even have sway bars! Can you recommend a place to buy the parts at reasonable prices?

-Mike

Jim Richards · 10-20-2006, 07:39 AM

Mike, I usually watch for used items for sale here on Pelican's classified ads. That's where i found the torsion bars. I also watch ebay, where I found the front sway bar. I forget where I found the shocks, which were purchased new. Good luck...early cars rock!

IROC · IROC's Garage

If you're leaning towards "ideal setup for comfortable street use" with only some track use, then I would stick with the 21/28s. I have 22/29s in my 2400lb '76 (w/3.2) and I would say it's a little stiff for anything but nice streets if you place any value on comfort.

I have red Konis vs the Bilsteins, BTW.

Mike

randywebb · 10-20-2006, 11:59 AM

How comfortable ?? And how bumpy are the streets??

I just drove my twisty & bumpy personal test track near my house and altho the city slapped some new asphalt patches down it still reminds me to REDUCE the stiffness of my torsion bars. I've tested cars with stock bars and with (IIRC) 28's (current car) on this same road back to back - many times. The result is that the less stiff bars are not only more comfy they are FASTER. So you need to compromise based on what you do.

Also, put the Wevo spring plates on - you want all the 'stiction' out of that suspension.

Jim Richards · 10-20-2006, 12:08 PM

Randy, are you sure reducing the t-bar stiffness is necessary? I think the ride comfort could be improved dramatically by revalved shocks. At least that's what I've been told. I plan to do just that myself one of these days (like my car's winter hiatus).

Micker747 · Micker747's Garage

Thanks,

the stock 23mm are way too soft, the exhaust almost hit the ground on hard accelerations....!

Maybe 26 or 27mm is better..? I'm running 195/65-15, so the tires gives a bit of comfort.

Jim Richards · 10-20-2006, 01:15 PM

Mike, you do have some extra weight in back with the 3,2L.

Micker747 · Micker747's Garage

Jim,

extra weight? It's all the same as before

Jim Richards · 10-20-2006, 01:22 PM

vs. a 2.2 that's standard on your car. When I ran a 2,4L in the back of my '73E, 26mm t-bars were reasonable for street/track use. My engine is now 2,7L, which is heavier, and I run 29mm t-bars in back. I was going to use 28mm, but went a step larger with no regrets.

randywebb · 10-20-2006, 01:23 PM

The DME motors are heavier than some of the earlier ones due mainly to the induction and exhaust. Not sure when the bigger oil pumps wer added; and chain ramps > 1984 add a bit.

re revalved shocks - I put new Bilsteins on. I doubt that revalving them will help much if any -- that is really for heavily modded suspensions AFAIK. e.g. look at the SRP guide in their catalog.

If the exhaust is hitting on accel, then something is way wrong - you may reallly really worn shocks.

tobluforu · tobluforu's Garage

I have a 72 with semi rs motor, lowered about 3 inches, adjustable bars, swayaway spring plates, and 21, 28 bars. It's a tad stiff on the road, but with car being that lowered and koni shocks on full hard-oh well.