Im continuing to sort out my 914, Still cant figure out what springs are in my car I just know they are heavy.

They appear to be heavier than the 550# I have on the rear of my 911 . The p/o told me they were from Racers Group but couldnt remember the what rate springs they were. Had the car on a lift yesterday took the wheels off and cant find any marks on the springs indicating the spring rate.

My friend has a selection of 7X2 1/4 eibach springs at his shop ranging from #350-#650 Im thinking of trying #450 up front and #350 in the rear. Do you think im heading in the right direction? or should I use the same rate at all 4 corners?

Any of you guys using 7" springs?

Thanks for any insight

Sorry felt the need to bump

Will I run out of travel with 7 inch springs? I know if the car is stiffly sprung, the suspension travel wil be less.

problem is I cant let the car sit on my firends lift for a few days while I get my springs measured.. ( he runs a business)

I stumbled on a selection of 7 in springs and am just wondering if Im pissing in the wind trying to use them

The rear of my -6 has 400# 12" Hypercoil springs. They sit near the bottom of the adjustment perch. It's about as stiff as I'll ever want it. I may eventually try 350# 10". I'm still sorting my car out so I can't say what's right yet.

Not that I'm a racer-type, but I find that hard to believe
that people would put >600lb/in springs in a 914, I mean
my frame would actually be the spring in that situation,
and I'm not kidding.

Mark S.
'70 914-6

Personally, I don't think the 7" springs are long enough. Also there is no need to run spring rates so high on a 914. After 5 years of racing in SCCA Production on slicks, I am upgrading to #250, 2 1/2" ID, 12" long springs. This accompanies a front swaybar upgrade to a big (1 1/4") hollow bar.
Truechoice has a chart that specs the dimensions of their various springs, such as length at coil bind, etc.
It seems to me you might have trouble mounting such short springs high enough on the shock to work, unless you have a highly modified rear suspension, with short shock absorbers.

I have a lot of success running 8 and 10 inch springs.

I'll revisit this thread later... busy right now.

B

My car has 911 RSR suspension, the front is the raised spindle strut, the rear is a fully threaded shock body.

The way the car sit with the 9" leave plenty of thread to raise the seats 2 in for a 7" spring. There is also the option of installing spring spacers.

Still learning how to set this car up. Ill probably end up using tie wraps on the shocks and measuring how much travel I actually use on the track.

OK Im back 914 newbie Had the car on my friends Hunter alignment rack, was able to get the rear dialed in.

alignment specs

FR -1.9 camber, 0 toe, 5.2 caster
FL -2.1 camber, 0 toe, 5.2 caster
RR -1.8 camber, 0 toe
RL -1.9 camber, 0 toe

I would have liked to get some more toe in on the rear wheels but ran out adjustment...what do you guys do to get toe in, in the rear? On my 911 1/8" per wheel is a good toe target.. I was looking to get some toe in........ prior to this adjustment i had 1/2 deg toe out on each rear wheel...

I also measure the springs and calculated the spring rate.... my results are #650 springs all around....

This sounds way to heavy for a #2100 car.

The guy who set up the suspension works for Kevin Bucklers race team... so I think he may know a bit about car set up but the springs are way to heavy....what do you guys think about #450 all around?

Thanks again..... any input is appreciated

Tim, if you can't get rear toe in I think something is bent or the geometry
was changed by whatever parts were put in. This wouldn't make me
feel that the previous guy knew what he was doing.

Instead of starting with some crazyass setup and reducing springs by
some arbitrary percentage, why not take something close to what the
people on this board use and work your way up if necessary.

Actually, I don't remember getting any details about the car design or
what you're going to to do with it. That is very important also.

Mark S.
'70 914-6

The car is a semi-tube frame, w/911RSR suspension, poly bushings,carrera brakes, and warmed over 3.2 six. I also scaled the car while i was doing the aligment it weighs 2157, so it can still go on a substantial weight loss program.

The p/o raced the car in PCA GT-3S, and the car was set up by a guy that works for Racers Group. Im just wondering what thought process led to installing such heavy springs?


I think next time i get to use one of my friends lifts, Ill install a set of #450 springs to give the suspension some compliance.

One of the biggest things which affects the ability to set toe in at the rear is when trailing arm reinforcements are added. The welding of plates to the trailing arms warps them in a way which alters the toe. It is possible to increase the slotting of the atachment bracket to offset this somewhat. I manufacture a heavy duty bracket to eliminate flex at this critical suspension pickup, and leave much of the slotting to the customer, so he can achieve the settings he desires.
Having said this, I don't think you want any toe in at the rear of your car. It will only increase scrub losses and tire wear. I have found that zero toe all around works very well. The tendency of the driven wheels is to toe in during power application anyway, to whatever extent the suspension allows.
More importantly would be the bump steer effect during cornering, where the loaded side of the car is compressed. The extent of lowering has a significant effect on bump steer characteristics.
As far as camber goes, you will have to measure the effect on uniform tire temps with a pyrometer, then reset cambers accordingly. It depends heavily on the type of tire and suspension stiffness, as well as driving ability. The harder you drive through corners, the more body roll will occur, thus affecting the tire patch. For instance, I use Hoosier 23x9.5x15 slicks on 7x15 wheels and require less than 1 degree of camber at all 4 corners. I try to obtain accurate pyrometer readings by driving into the pits off a hot lap, avoiding a cooldown lap when I want good readings. I measure the outside rear tire first because it is the hottest, and the temps will degrade the fastest, then the outside front next. I make pressure readings last because they change much slower than the temps.
On the subject of spring rates, I think that the lowest rates which achieve good contact control are the best. Use higher antiroll bar rates to control body roll as much as possible. Also the shock valving must be matched to spring rates or they won't operate effectively either. Since you aren't experienced with a car like you now have, I suggest no higher than #350 rate springs all around, unless this would compromise the shocks you already have.

Thanks Chris,

What you have mentioned kind of confirms some of my suspicions. I was wondering if the trailing arms could have been distorted when they were reinforced.

I keep falling back to my 911 set up habits with this car. on my 911 i set up the rear with 1/8"total toe and 2.5 deg neg camber, the front is 3 deg neg camber with 0 total toe. On the 911's with hoosiers or slicks we try to dial in as much camber as we can..

I have a feeling the shocks and struts are valved as they came from bilstien. I happen to have a extra set of #450 springs. Its easy enough to swap springs so Ill try what I have. Ive been trying to get in touch with guy who set up the car but he is busy with Racers Group right now

Thanks for the input

Chris' response almost echo's what I would have told you (I'm revisiting a little late)

Something that sometimes goes unoticed: set the car up for your tracks. If you have tracks around you that are 90% left hand tracks... set the car up to go left. Run more negative camber in the right front than you do in the left front.


Sounds like a fun car. Run the 350's and get back to us with some tire temps and pressures the first time you run it.

B