Made lots of changes, now it pushes, Yes, I know I shouldn't have Options

[nhallman]

OK, so I finally decided to do some suspension upgrades on my autocross car ('75 1.8), and I kind of did everything at once (yeah, yeah, I know):

Koni yellow shocks/struts
930 tie rods
22mm Weltmeister front sway bar
180# Weltmeister springs
disconnected (stock) rear sway bar

I was sort of following an old (mid-90's) Weltmeister guide for autocross setup that I found on the Pelican board, except they recommended 21mm torsion bars up front. I sort of ran out of cash, so I left the stock torsion bars on the car.

So, I figured that by not stiffening the front as much as recommended, but making all the other changes, the car would tend toward loose (especially since that's how I tend to drive it). Wrong. It pushes... badly.

When I made my first few runs, I had the Koni's on full stiff. I took a full turn out of the front and that helped, but the car still pushed. I played with pressures, taking 3 lbs. out of the rear (Kumho V710's - an R compound tire), leaving the front at 35 lbs. and the rear at 32 lbs. That helped, too, but it did still push and was a concern because the car had been so neutral prior to the changes that I rarely had to adjust tire pressure.

So... now what? I have all this adjustment available to me, and I don't know what to try.

My fear is that in my quest to get the car back to neutral, I'll take away some of the major gains I've made in grip (did I mention it did stick like 500% better?). I don't want to do that.

My thoughts (ranging from simplest to craziest):

- adjust my driving style and deal with it
- soften the front struts even more
- loosen the front sway bar (currently set to full stiff)
- reconnect the rear sway bar
- set the rear toe to 0 (currently 1/16 toe in, front is 3/32 toe out)
- cut a coil from the rear springs (only a consideration b/c I can only get ~1.2 deg negative camber in the rear - all shims removed)

Any ideas? I'm a fairly experienced autocrosser with a lot of seat time in this car, but I'm a total novice at suspension setup. I just tended to jump in the car and drive it up till now.

TIA...

[jhadler]

- adjust my driving style and deal with it

I'd consider that if all else pans out.

- soften the front struts even more

Why, it won't fix the problem. A lot of people adjust Koni's like they're adding stiffness to the spring rate of the car. That's compression, and Koni's (at least single adjustable ones) only adjust the rebound. The intent is to match the damping of the shocks to the spring rate of the car. Not to increase or decrease spring rate.

- loosen the front sway bar (currently set to full stiff)

VERY likely your culprit.

- reconnect the rear sway bar

An option, but most would say that leads to wheel spin with stiffer springs. Especially with a stiffer front bar.

- set the rear toe to 0 (currently 1/16 toe in, front is 3/32 toe out)

Toe sounds good.

- cut a coil from the rear springs (only a consideration b/c I can only get ~1.2 deg negative camber in the rear - all shims removed)

DO NOT CUT THE SPRINGS!!@!#$#% Better to just get a coil over kit for the rear shocks, and corner balance the car. Then you can also adjust the ride height to your liking.

-Josh2

[nhallman]

Why, it won't fix the problem. A lot of people adjust Koni's like they're adding stiffness to the spring rate of the car. That's compression, and Koni's (at least single adjustable ones) only adjust the rebound. The intent is to match the damping of the shocks to the spring rate of the car. Not to increase or decrease spring rate.

Thanks, Josh... this is exactly the kind of thing I was looking for.

One question... ARE Koni yellows single or double adjustable? I can't find any info on them, and the stick figure drawings that came in the box with the shocks were worthless.

I know the knob at the top is only adjusting rebound... is there another adjustment?

[DanT]

Why, it won't fix the problem. A lot of people adjust Koni's like they're adding stiffness to the spring rate of the car. That's compression, and Koni's (at least single adjustable ones) only adjust the rebound. The intent is to match the damping of the shocks to the spring rate of the car. Not to increase or decrease spring rate.

Thanks, Josh... this is exactly the kind of thing I was looking for.

One question... ARE Koni yellows single or double adjustable? I can't find any info on them, and the stick figure drawings that came in the box with the shocks were worthless.

I know the knob at the top is only adjusting rebound... is there another adjustment?

not unless you have some really old Konis with a knob on the bottom (on the rear shocks). Or bought some very expensive "race" shocks. But they wouldn't be yellow IIRC.

[Joe Ricard]

To fix your push loosen the front bar.

Also what kind of camber do you have infront? What were your tire temps across the face for all tires.
Don't mess with air pressures till you know where the heck you are at temp wise. V710 can go down to the low 30's on these light cars IF YOUR TEMPS ALLOW IT..

[ConeDodger]

Take your front bar back to full loose and then move back from there.

The tendency seems to always go full stiff... It's like if a little is good then a lot should be way good. It isn't. Sneak up on neutral by going full loose and moving stiff by baby steps.

I doubt you have double adjustable Konis. Rare and old. Seems to be a rash of them showing up lately though.

[grantsfo]

My 1.8 had exact setup for a short period. Didnt see what you had for camber in the front. What size wheels/tires are you running?

I ran with front bar set about 1/2 way to full. Front koni's set at 3/4 firm and rears full firm. Front camber was about -2.

When I ran 8" wheels with 205/50/15 Hoosier A6 tires the car turned like crazy. With stock fuchs and Yokohama A032's it pushed more and I had to adjust my driving style.

[nhallman]

Tires are 205/50/15 Kumho V710's on stock 5.5" wheels.

I can't get more than 1 deg neg camber in front and about 1.2 deg in the rear. I have the front adjustment on the strut towers pushed as far negative as they will go, and all shims removed in the rear..

[DanT]

Tires are 205/50/15 Kumho V710's on stock 5.5" wheels.

I can't get more than 1 deg neg camber in front and about 1.2 deg in the rear. I have the front adjustment on the strut towers pushed as far negative as they will go, and all shims removed in the rear..

that doesn't sound like much negative camber front or rear.
how low is your car?
you need a minimum of -2 in front to get the car to turn in very well, regardless of the torsion bars, sway bars, or shocks.

[nhallman]

I'm not exactly sure what the ride height is, I was having trouble getting an accurate measurement. It's only slightly lower than stock, though.

So, I can get more neg camber in the front by lowering the ride height, but what about the rear? What can be done there, and how much neg camber do you recommend?

I do still drive this on the street, but tire wear isn't a huge, huge issue... it's only money, right?

[jhadler]

Camber. Gotta get it. If you don't have it, find a way to get it.

Camber really doesn't wear out tires as nearly as much as toe does. And actually you can get longer tire life (for a car that autoxes) with more camber as you're not riding on the shoulder of the tire all the time. You'll also get better grip.

Front camber can be found by lowering the front of the car using the factory torsion bar adjusters. But first start by getting the car aligned and set the camber plates to as far back, and in, as you can. A _very_ common practice is to have the slots for the bolts of the camber plates widened, so you can get more caster and camber.

Rear camber can also be gained by lowering, but best to do it with the proper shims. In general, a 914 neds a little more front camber than rear.

To solve your push, the cheapest and easiest thing to do is soften the front bar. Start by going to 50% on the adjuster (It's a welty right?). If it's still pushing, try 25%.

If, after softening the front bar, you still have a push, look into getting a good alignment done. Get as MUCH caster, and as much camber as you can get in the front. If you have to sacrafice a little bit of camber to get a little more caster, do it. Caster is _dynamic_ camber. The more you turn the wheel, the more camber gain you get.

The change from little caster to a lot will shock and surprise you. If you've only got minimal caster right now, dialing in a lot will plant the front end and the rear will have little choice but to swing around... Caster is gooooood. (IMG:style_emoticons/default/cool.gif)

-Josh2

[nhallman]

I have the front caster set to the max. Slotting the bolt holes didn't seem to be much of a help, because it didn't seem like there was enough room at the top of the strut to even move it over any further... it's a tight fit under there.

As for the rear, removing the shims from the trailing arms makes camber more negative, correct? I've removed all of them.

[jhadler]

Then it may be time to see if your chassis is straight. You should be able to get a little more camber than that.

-Josh2

[nhallman]

Then it may be time to see if your chassis is straight. You should be able to get a little more camber than that.

-Josh2

OK... when I had the stock setup on the car (stock springs, stock sway bars, original tie rods), I had -1.5 deg camber in the rear (with 1 shim still in on each side) and -1 in front. When I switched to this setup, I was *barely* able to get -1 in front (it's actually slightly less) and rear camber went to -1.2 deg, even AFTER removing the shim (before, it was ~.9 deg).

So what changed? Is there some adjustment I've missed here? I removed both rear trailing arms to replace the bushings and rear wheel bearings, and I had the entire front suspension apart as well.

And... failing that, what can be done to achieve more neg camber in the rear... that was why I was considering cutting coils...

[jhadler]

You've already got Koni's right? Get the adjustable threaded collars for the rear shocks so you can lower the rear. Lowering the car will get you more camber.

With adjustable ride height on all four corners, you should be able to get a good corner balance on the car as well...

-Josh2

[nhallman]

You've already got Koni's right? Get the adjustable threaded collars for the rear shocks so you can lower the rear. Lowering the car will get you more camber.

Guess I should have thought of that. I didn't realize any existed, but sure enough... it appears that for my shock (8241 1050Sport), the 50mm ID sleeve and perch (30.0000.0005 and 30.0000.0006) from Koni will work.

Unfortunately, I can't seem to find ANYONE that sells these. Paragon, Pelican, Performance Products - nil. I've gone through a bunch of the resellers listed on the Koni site, with no results, either.

Does anyone know where to find these?

[jhadler]

Not sure why you can't find 'em anymore. But try Ground Control. They are a huge suspension seller, and if they can't help you, a good custom suspension shop should be able to do something. Really, the threaded sleve and collar are not rocket science. Heck, I knew someone who made their own threaded collar and perch out of plumbing supplies (trekkor, you reading this?). Not that it would be my first choice though...


... Okay, I just called ground control. You can get 'em from them for $199.

Now keep in mind that you'll need new springs, as the standard spring for a 914 does not fit a modern coilover setup. On the plus side, you can now get ANY spring weight and length you want for something like $50.

-Josh2

[914forme]

That is very minal camber there. You will notice that the tops on your stuts, can be swapped side to side. It might help you with a little extra. You get them mixed up????

The rears should be able to go way more than that also, the rear shims come in different thicknesses, also.

Another thing I see is you changed your bushings. That could have changed your posistiion also. The down side of deformed bushings is that they are compliant. So at rest you could be getting a very bogus reading, they would have had to let your front arms push out but it is possible. The rears it is much more doable that the bushings allowed for a higher degree of camber.

Nothing wrong with changing everything at once. Now just change one thing at a time and see the results, keep notes and understand what hte changes you do, and how they effected your car.

BTW, 5.5" are kinda narrow for hte V710s yes lots of people do them, but I would recommend a rim width increase myself. And yes they are on Kumho's size chart for hte tire but I consider them small for that app. I would run 7s or 6.5s if you can find them.

I happen to be one that run a rear bar, it could be used to increase rear stiffeness and thus help balance out your car. But you do run the risk, of wheel lift. I have in the past.

[nhallman]

Awesome... thanks for checking on that, Josh.

So the Koni page says any spring with a 2.5" ID should fit on the perch. Are the Weltmeister 180 lb. springs too small? Too large?

I'll check the tops on the strut tower... I could very well have mixed them up. I wouldn't put it past me. :-)

About the shims on the rear. I have removed all of them, which made the camber more negative. If all the shims are out, then I have no more adjustment I can do, correct?

New wheels are on the list, I've held off because I'm kicking around the idea of flares which will of course significantly affect what wheel and tire width I run.

[nine14cats]

Awesome... thanks for checking on that, Josh.

So the Koni page says any spring with a 2.5" ID should fit on the perch. Are the Weltmeister 180 lb. springs too small? Too large?

I'll check the tops on the strut tower... I could very well have mixed them up. I wouldn't put it past me. :-)

About the shims on the rear. I have removed all of them, which made the camber more negative. If all the shims are out, then I have no more adjustment I can do, correct?

New wheels are on the list, I've held off because I'm kicking around the idea of flares which will of course significantly affect what wheel and tire width I run.

Several of us have found that 2.5 ID springs with a 10 inch length work well with the Koni's or Bilsteins and adjustable collars. Now you can get into the discussion of progressive versus linear rate springs..... (IMG:style_emoticons/default/biggrin.gif)

Thanks,

Bill P.