OK guys. I've got a handling question., I've got no experience setting up a mid engined car for taking on Options

[Dr. Roger]

Here's where the car stands.

Front:
911 Targa front suspension
22mm Elephant Racing torsion bars
Bilsteins
8X18 Hollow spoke turbo twisties
Almost new Pilot Sports
About 1.5 degrees of camber.
Minimal caster and toe.
No sway bar.

Rear:
Koni Sports set on stiff rebound
150 lb. coils (and no, I'm not going stiffer. I have back problems as it is)
11X18 Hollow spoke turbo twisties
Almost new Pilot Sports
Approximately 2 degrees of camber.
Approximately 0 degree of toe
No sway bar.

I'm finding the car is predictably over-steering with balanced throttle.

Is there a way to adjust either of the suspensions to get a more centered drift and less over-steer given my current setup?

All suggestions are greatly appreciated.

Cheers. (IMG:style_emoticons/default/smile.gif)

[nebreitling]

install front sway bar. an adjustable 19 or 22mm ought to do the trick -- or even a stock bar. will help your handling and won't adversly effect ride quality.

[Dr. Roger]

That puzzles me. I can barely compress the front suspension 3/4" and you're suggesting I make the front suspension even more "sway resistant"?

I do have both stock and race front sway bars collecting dust. Tabs are already on the A arms.

I guess I've been afraid to tackle this installation as I've never installed one before and I don't want to screw up getting the bar too close to the gas tank and then REALLY F** things up.

[Chris Pincetich]

(IMG:style_emoticons/default/agree.gif)
Maybe those underbody 911 types would work best as far as being easier to install on your 914.

Now, if your problem is too much throttle oversteer, be jentle on the big pedal to right (IMG:style_emoticons/default/biggrin.gif)
(IMG:style_emoticons/default/beerchug.gif)

[Andyrew]

Predictable over steer with a balanced throttle is what you want. IE if you can control it 100% with ease and make it do what you want..

If you want to lay on more throttle during the corners, YES add a front sway bar.

Besides its not that hard, all 914's have an embossed area for putting the say bar.. Do a search, Orange914 just did this. No way for you to fuck it up.

BTW you have too much camber on the back vs the front. take a degree off the rear and see what that does (you'll need some shims and an alignment) You should be at 1/2 a degree or more added to the front than you do the back. Also your tires will wear more.

Andrew

[nebreitling]

your set-up is a bit unusual (no sway bars, big T-bars, relatively light springs), and i'm a bit surprised that it would oversteer -- unless it's entirely throttle-induced (IMG:style_emoticons/default/biggrin.gif) .

either way, increasing the front roll rate will help your cause. for a street car, i would prefer 19mm t-bars and a bigger sway bar (would ride smoother).

a sway bar install is easy -- don't worry, you won't screw it up.

your only other real option for the street is to decrease rear spring rate, or start playing with tire sizes, compounds, etc...

[nebreitling]

i don't necessarily agree with Andrew on the rear vs. front camber thing for a 914. YMMV.

[Jeffs9146]

3/4" front suspension travel is not enough! Your car is too low for the suspension to properly function. You should consider lowering the spindles if you need it that low!

My .02 cents.

[DanT]

i don't necessarily agree with Andrew on the rear vs. front camber thing for a 914. YMMV.

(IMG:style_emoticons/default/agree.gif) I have always had more negative in the rear than on the front on every track car I have owned.
4 914s, 2 911s, 1 951 and my Boxster all run more negative in the rear with good results.
Everything in moderation....
my current set up is -2.25 in front and -2.75 in the rear on the Puttputt.

[Andyrew]

I was talking about street setups, but hey you guys definately know more about that then I do.

[nebreitling]

3/4" front suspension travel is not enough! Your car is too low for the suspension to properly function. You should consider lowering the spindles if you need it that low!

My .02 cents.

i think (hope!) he's talking about how much bump he can achieve by pushing down by hand -- not total travel. otherwise, he definitely has a problem!

22 Tbars are definitely well on the stiff side for a street car.

[dan10101]

Roger,
Here are a couple charts that may help understand what does what when dealing with understeer and oversteer.

http://www.derporsche.net/links/steer.htm

http://www.ffcobra.com/FAQ/handling101.html

Dan

[Demick]

As to the camber discussion: you normally need more negative camber in the rear. Reason is, whatever camber you have there is fixed, while in the front, your caster turns into negative camber when you turn the wheel - so in reality you are getting more negative camber in the front in a turn than you measure statically with the wheels straight ahead.

[Dr. Roger]

Wow, I'm glad I asked the question. (IMG:style_emoticons/default/thumb3d.gif)

I Googled for an hour trying to find a real world camber spec for 11" wide tires on a 914 and came up with nothing.

Yes, the 22mm torsions are way too stiff for a performance/street application but they came with the front suspension (off of a wrecked 914 track car).



Nate, Dan, and Dan,
I appreciate you all sharing your suspension setup experience with me. You guys are real racers. (IMG:style_emoticons/default/grouphug.gif)


I think I will see if anyone local wants to swap their 911 20mm torsions for my 22's. I wonder what Andy's running???? LOL
(IMG:style_emoticons/default/driving.gif) (IMG:style_emoticons/default/clap56.gif)

Then install that adjustable front sway bar.... Yikes... (IMG:style_emoticons/default/barf.gif)

[Dr. Roger]

Oh, and Demick,

I think 914's have "semi-trailing" arms at the rear which actually sees some camber increase as the load is increased in a turn.
Regular trailing arms see no change in camber.

[Dave_Darling]

Try softening the rear shocks before you go bolting parts on. That should give you a little better front grip.

Yes, it's counterintuitive--but stiffening one end of the car makes the other stick better!!

--DD

[Dr. Roger]

Thanks Dave,

I will loosen my rears shocks a little and see what that does for me.


Unfortunately I think I threw a rod yesterday running the twisties up at Grizzly Peak Blvd. in Berkeley. I guess I'm not the engine builder I thought I was. (IMG:style_emoticons/default/alfred.gif)

I did find 2 threads on front sway bar installations and both were VERY helpful. I actually think I can do it. (IMG:style_emoticons/default/boldblue.gif)
here
http://www.914world.com/bbs2/index.php?sho...c=70221&hl=
and here
http://www.pelicanparts.com/techarticles/9...ont_swaybar.htm

I have run out of money at this time so Bebe will take a little rest for now as I continue my plans (studying for the CA Real Estate license).

I will be playing with paint schemes and installing that adjustable sway bar in the mean time. I've gotta' say this car has been an adventure to say the least. (IMG:style_emoticons/default/driving.gif)

[nebreitling]

also, your alignment specs are pretty loose. for a V8 car with loads of power, i'd really be looking for some rear toe-in. that should help plant the rear. you may see where that gets you before you bolt on parts.

additionally, unless your steering is too heavy with those monster tires, i'd increase your caster. most guys run as much as they can in these cars. yes, that will help stick your front end (potentially making things even more loose), but if you're going to add a sway bar anyway, then it's easy to tune out. in any case, adding that front sway bar will help keep your inside-rear down, which will help stick the rear -- especially if you don't have LSD. sway bar install will only take a few hours if you don't stop for beers.

[Dr. Roger]

Hey Nate,

Yes, that's right, I did adjust my front caster to a minimum to reduce the heavy steering and for less fatigue running the twisties. Of course the price I paid was to reduce high speed stability. I have to pay more attention when driving the highways.

With added caster it is reassuring to have such great straight line stability when running her above ***MPH. =) Maybe I'll add a little bit now that you mention it.

Is rear toe-in to compensate for hard braking? Or shouldn't it be toe-out for hard accelerating?

I think my MBZ and my old Maserati both had toe-out on the rear suspension. (IMG:style_emoticons/default/confused24.gif)

[nebreitling]

yikes! w/out commenting on your mbz and maserati (not familiar), i will say that few performance oriented RWD cars will run rear toe out (which will cause, errrr, rear wheel steering!).

i'd run 1/16 in per side, if not a bit more. will also increase your high speed stability. zero toe up front, or a bit of toe in if you want the stability (at the expense of turn-in).