I posted this on Pelican Parts back 9 months ago one day when World was down, so some of you may see overlap....

I need some help with Huey in getting it to handle right. I'm embarassed to say this, but in the past, I had my mechanic just put on what he thought was right. Worked great, but as time has gone on, I do a lot of the work myself so I really have no idea what was done in the past. ask me about anything on the car, and I'm good....except my suspension.

Anyway, we do not have stock 914 suspension: when we upgraded to 5 lug, I guess we put 911 stuff up front. 3.5" spacing for the caliper ears, (though we run 993 rear calipers on the front), and bilsteins. 22mm Welt adjust front sway, and I HAVE a Welt rear sway that is currently disconnected. Bilstein in the rear. 180# springs.

I am getting TERRIBLE understeer, never oversteer either with or without the rear sway connected. In fact on the track, were were getting the front inside wheel to lift, even getting a bit of that on an autocross. I'm thinking maybe the front sway is too stiff?

Basically, I have no bite in the front, it feels more like an old 911 that wants to just push through a corner.

I was told that I can't put 914 Koni adjustables on the car (someone on here has them for sale). Is that true? And based on what I have, what is the best suspension set up. for AX/Street use?

Thoughts?

There are tons of elements to play around with, but one point to consider is that many guys with race or dual-purpose cars run significantly stiffer rear springs (200-300lb) as well as front torsion bars (21 or 22mm or more). That's a good place to start if you want to flatten the car. Then you can fine-tune things with the swaybars. If you do not want to change spring rates right now, you can try backing-off the front bar gradually to see if that helps the turn-in.

Also, tire pressures can be a factor. What tires and pressures are you currently running?

Whats the front torsion bar diameter?

22mm front torsion bars

I saw that in the thread at PP when I looked in there.
That should provide a decent balance with the 180# rear springs.
You must have the anti-sway bar set pretty stiff.

How low is Huey? Are the spindles raised?
Do you have any kind of bump rubbers on the front shocks?
Are you sure the shocks aren't running out of travel? If they become fully compressed the spring rate rises suddenly which will cause a loss of grip.

It should be possible to make the car oversteer with the throttle when the suspension is set up well.

Bob,
I have pretty much the same set up. I have 21mm bars in front and 180lb springs, and a 19mm swaybar. As Chris says if the car is too low you run out of travel. I can dial in oversteer or understeer with the front swaybar. You need to loosen the swaybar and make sure the drop links are equal.
Good luck
Van

How low is Huey? Are the spindles raised? Not exceptionally low, lower than stock, but still street driveable. It's not hear right now or I would go measure. Spindles as far as I know are not raised. Probably can't tell from a picture, but here's one anyway.
Do you have any kind of bump rubbers on the front shocks? Good Question...
Are you sure the shocks aren't running out of travel? Another good question, in addition to the question of "Are you sure the shocks aren't completly shot and not doing much for you to begin with"....since they came off of an older car...




I'm going to start messing with the front sway, see what that does.

Now, another stupid question that I think I know the answer to but want expert feedback: rear sway bar - if it's disconnected, won't it induce understeer more than if it's connected? and...if I'm getting too much understeer, shouldn't I reconnect the rear?

Like I said previously, I realized I know nothing about 'stock' 914 suspension. I now need the little adjustment knobs and nitrogen canisters to do set up like I have on Papa Smurf...

Bob,
Call Koni and get their sport front bump rubbers or cut yours down. Hooking up the rear bar should produce oversteer. To keep from getting too much bump steer raise the steering rack with spacers and keep the A-arms level.
Van

With *21mm* front T bars, 275 lb rear springs, no rear AR bar, my front AR bar is set at half hard. It's a matter of balancing front to rear spring rates. Shocks & AR bars are for fine tuning after you get the spring balance close.
Mine still lifts the front inside tire.....but it goes where you point it.

What are your corner-weights?

None of this will get you anywhere unless your corner balance is where you want it to be.

Connecting/disconnecting the rear sway bar should make a noticeable difference.
Andy

With my weight (215 with gear) in the drivers seat it's:

FD 576 514 FP
RD 682 631 RP

49.8% x 50.2%

Yes, it's heavy (with me, full cage, 1/2 tank gas, all the oil, oil lines, cooler, etc...weight is 2403.

Its the absolute best he could do. Jim Burton at Eurowerks is an expert in corner balance/car set up. He's done it with Rolex teams and all..... and what he did with Papa Smurf transformed the car, but we have much better control on set up.

Remember, this is the wrecked and fixed chassis from Targa Newfoundland. It's pretty close to straight but not perfect. I know that this will affect things, but I'm more looking for what is the best I can do with what I currently have, or can easily upgrade.

The crossweights look great.
It wouldn't hurt to get some more weight to the front, you seem a bit heavy on the rear.

My setup is similar to yours except i'm running 250lbs springs in the rear and have the rear bar connected.
I also run roller bearings in the rear which respond better than the rubber bushings.

Double check to make sure you get enough actual travel on your front shocks. If you bottom out on the rubber stops, your shock rate goes to infinite and the front won't stick.

Did you try to disconnect the front bar and see what the car does?
Andy

The problem I'm having right now is that we are doing all this discussion...and I don't have my car! It's at the shop getting a few engine tweeks worked out, so I haven't had a chance to mess with set up. we had an AX this weekend that I had to miss. The reason for my questions last week was so I could do some adjustments at this AX, but unfortunately....no car....

I get it back Wednesday then drive it down to Petit LeMans. Thinking of bringing it to our DE the following weekend and giving me a chance to do some set up...

I lowered the front-end on my car (about 3/4") and it got alot more bite in the corners, not sure why it made a huge difference. I was thinking maybe it gave a different pre-load on the torsion bars... last time at the track it did really good... I was pushing at the ax's, I'll report after this weekend and let you know how it runs with the front being lower.

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Hi Naro914:

You have gotten a lot of helpful information and it may seem confusing which to use and which does not apply to your car. I hope I can help. My 914 is a V8 conversion which I drive on street and track, like you. I've working on the handling for some time and have learned some basics that apply to ALL 914s.

Spring Rates: I attached my Excel spreadsheet that calculates spring & swaybar rates and finally ends up with the WHEEL RATES...that's the number that matters. Why: given the spring mounting, the rear wheel rate is 117.38 times the spring rate.

With your numbers plugged in, you can see that your wheel rates are very close to the SAME front to rear. JPStein offered your same setup with 275 lb/in rear spring as something that worked for him. It is obvious that you need more rear rate relative to front spring rate.
MY SUGGESTION: Go FULL soft on the front bar and TEST the car. See how it feels. Then RE-ATTACH the rear bar. Now you have softened the front and stiffened the rear. Now TEST DRIVE the car. It should get better, make notes.

If you like the feel: Great. If it s not there, you can try disconnecting the front bar and TEST DRIVE the car. If you STILL have to much understeer, want a stiffer (more responsive) car, then it is time to go up in the rear spring rate.
I would suggest going up to 300 lb or more: Why? 1) extra in the rear rate will allow you balancing-adjustment with the front bar and 2) I found that 400 lb/in springs still gave a reasonable ride on the street. If you have 2" (NON-914) coil-overs SummitRacing.com and great prices on 10" springs.

SHOCKS: First off: buy a copy of Carroll Smith's DRIVE TO WIN!!!! It is the best thing I have ever seen on setting shocks!
I'm running Koni sport shocks in my 911 boge front struts and have found them to be very good. The control REBOUND only, but that is what helps the front get bite according to Carroll. If you can afford the cost, the Koni 6811 series struts shocks are Dual-Adjustable, but the best price I found was $314ea.

For the rear, I sent my old shocks to Koni and had dual-adjustable guts inserted.
I am vehement about JOUNCE/REBOUND adjustment in the rear as the JOUNCE control is what just got my car right!: stable & drivable. However, they were much more EXPENSIVE than the 6811 fronts. So if I were to do it again, I'd buy a Standard Product koni dual-adjustable shock. This would also get you into a standard 2" coil-over shock design with ride height adjustment.

Suspension settings: Since you are running radials on relatively soft springs, I would recommend -3 degrees all around. Before I made my car STIFF, I had perfect wear patterns across the Yokohama 245 fronts and 315 rears with -3 degrees. If your car is also a daily driver, you would probably have to back off the aggressive camber to -2 to -2.5 degrees. (I am currently at -2 with 450# rear springs) So camber HELPS.

Caster: stay with stock

Toe-in: THIS IS A BIG ISSUE FOR 914s. I did a big post about it on the thread: "Alignment specs for V8 DE 914". The short version I suggest 0 to 1/16" toe-in at the front. Racers run toe-out to aid turn-in, but again the trade off is that on the street ,with uneven payment, the car gets nervous....but not scary.
REAR-TOE: This is the big issue in that when the car rolls into a corner the LOADED wheels moves up and toe-in. I measured .200" toe-in GAIN for 2" of travel. At the same time the UN-LOADED wheel goes TOE-OUT at the same rate.
The clever Porsche engineers designed a rear suspension where BOTH wheels point into the corner and almost eliminates OVERSTEER. This was doubtless due to Ralph Nader and lawsuit worries. I have set my car at 1/16" toe-in per wheel and may go less. At Laguna Seca Historics, a Porsche specialist told me he sets 914s with TOE-OUT in the rear.
My Suggestion: With all the adjustments above to decrease understeer, BEFORE you spend $$ on rear springs, try setting your rear to toe-out at 1/16" per side and TEST DRIVE the car. If you like how it feels, try MORE toe-out. Keep in mind that you would have to go to .at least 200" toe-out to end up at 0-toe when loaded in a corner.

Ride Height: just looking at your car 's photo tells me the ride height is not a negative factor. 914s CANNOT be lowered much before screwing up the camber arc of the suspension. To truly lower a 914, racers and REMOUNTED the suspension UP in the car. I run my car at 5" at the sheet metal bumps at each corner of the underside of the chassis.

Corner weight: I used to use bath room scales to balance out my Formula Ford, but for a street car, it is 1)hard to do and 2) nearly impossible to achieve. That said, your car is fine.

I hope this give you some help on setting up your car. The only other suggestion is READ tech books on racecar suspension and setting.

Best,
Terry

you want to try that again Terry?

Thanks Terry, that is a BIG help. I may have a few more questions as I go, but that gives me something to work with.

FYI, I softened up the front sway and it made a bid difference even on the street, so we'll see how it does on an AX, though none scheduled anytime soon...

Hey Naro914,

I'm glad I could help and would enjoy tackling any further questions you have. While I tried to explain the "Why" of my suggestions, I know I haven't done so completely, so feel free to ask away. If you would like to email directly where I can attach any number of photos, try porschepiloto914@verizon.net.

BTW: I've had the luck of being befriended by a VERY sharp engineer/racer. He is the best Race-Engineer I have seen and comes to all my track days to sort out my car, while I watch and learn. He is the genius behind getting my car where it is now: He makes a suggestion and I do the work (his brains, my brawn) He is also a forum member and has always said: 1) change 1 thing and a time and test and 2) EVERY time you go out for a track session, CHANGE SOMETHING as a way to learn more. We keep making changes (now getting smaller & smaller) and we keep learning more about the 914 chassis. I have to admit resisting his methods at times, but have learned how right he has been!

Hey, I went to your web site and see how active you are with PCA and other events. Great fun! I'm really envious in your runs in the Targa Newfoundland!!
I LOVE watching the coverage of the event on SpeedTV and will look for your car
at the next running. I'm thinkin' that with so many tight and gravely corners there,
you would find understeer VERY scary!! Well, I KNOW you can get that turned around.

Best,
Terry

Terry,
Yep, very active with PCA. I'm actually the Zone 3 Rep for PCA - meaning I'm middle management I guess. My job to help out the regions in the southeast with questions and procedures and such. Really good gig honestly, lots of fun.

Yes, Targa is a blast. We may go back one day, even thinking of doing Targa Tasmania someday in Australia!!! We'll see, gotta get my company to be profitable at some point to afford that adventure. We have friends over there that run Targa Newfoundland, so they can help us out...