Handling issues - need adjustment advice Options

[Brian Fuerbach]

When driving large sweepers like freeway on ramps at high speed I experience what I can only describe as front end scrubbing. Not understeer, more like the front is just not planted and tracking. Things get better with a full tank of fuel. Is that just the nature of the 914, full tank factored into weight bias, or can the suspension be tuned to emulate the weight.

Here is what Im working with;
-19mm adjustable sway-bar set about 1” back from full soft.
-Koni yellow adjustable shocks
-Stock front torsions
-Rear springs are aftermarket (reddish orange color) but I do not know the poundage.

Any input would be appreciated.

[roblav1]

Soften the end that's not working. FARB is probably too stiff. Probably too much front toe-in too.

[Superhawk996]

Soften the end that's not working. FARB is probably too stiff. Probably too much front toe-in too.

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I think you've got to much stiffness on the front between the dampers and the Anti-roll Bar (ARB).

As Brant suggested. Move the ARB links toward the absolute end of the adjustable bar. I.e. increase the length of the arm - decreasing stiffness of the front ARB.

As Roblav1 suggested. Dial out dampers (softer). Adjustable dampers are only adjusting rebound damping. Lots of front rebound damping ends up fighting the ARB on the inside wheel. In additon, the net effect of too much front damping only further stiffens the front end in addition to the what the ARB has already added.

What we're working on here is to soften the front end relative to the rear.

My impression is that you like the extra body roll control that the front ARB added but that it's been over done with the 19mm front bar. I don't think you have mentioned yet if there is a rear bar. The OEM set up added a bar on both front (15mm) and rear (16mm). The dual bars provides a more balanced split of body roll control. If you don't have a rear bar, you're trying to do all roll control off the front end which stiffens the front end, inducing steady state understeer.

When you added some damping to the rear, you stiffened it - which has the same net effect as softening the front end relative to the rear. Hope this makes sense the way I've written it.

All tuning is done on a relative basis. You can soften the front or stiffen the rear for the same net effect. Sometimes you will have to do both to achive a desired result. But for right now, no need to get into additional rear spring or damper changes. Just work on one end of the car at a time with the overall direction of softening the front relative to the rear. Ideally, you work on the end you want to affect. I.e. if you want to soften the front; do the work in the front. When you run out of front "knobs" to turn then you can start stiffening the rear further.

I'm in Pasadena and do some suspension tuning on the side if you want to drop by and show me what it's doing.

Take Yeahmag up on this. It is always way easier to tune when you can see and feel what is happening vs. trying to do it by words on a forum like this.