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View Full Version : Alignment questions? (Help an Auto-xer, please!)



bfrance
06-08-2003, 09:30 AM
Hello,

First off, I know this is an IT board, but I have yet to locate hardly any auto-xer's that run the 240sx chassis, so here goes.

I have a '89 240sx hatchback that I autox and daily drive and I am having some issues with getting it sorted. My problem is that it always seems to push on the auto-x course. I'm running KYB AGX shocks, (adjustable for rebound only, I believe that bump is fixed,) Whiteline springs,(linear rates, slighlty stiffer than stock,) with poly t/c rod bushings. The tires are stock size, (195/60-15,) Yoko AVs intermediates, stretched over a 15x7 enkei rim.

Alignment specs are as follows: 1.75 degree negative camber front, 1.5 degree negative rear, 0 toe front and rear, (in the interest of tire wear,) and castor at stock,(non adjustable.)

I usually start the day with the tire pressures at 42 front and 38-40 rear and then adjust from there.

My problem is that the car seems really sluggish to turn, and it always pushes. I've even resorted to clutch-kicking it a couple of times to try to get the rear to rotate, but that isn't the fastest/most predictable way to achieve it, as you all know.

Any ideas?

Thanks in advance,

Ben France

Tristan Smith
06-08-2003, 11:00 AM
Ok, I'll take a stab at it.....and please help me out guys. Disclaimer: I am a racer, not an autoxer, so I'll tell you how we would fix it for the track.

There are a couple of ways to eliminate push. First, reduce your front tire pressure a few pounds, and put a few more in your rear. Keep adjusting the pressures until you feel a difference.
You didn't mention what type of sway bar you are running, so I'll assume it's stock and non adjustable. If you have any adjustment in the bar, soften the front bar up.
You did say you have adjustable shocks. I would think that the compression is the adjustable factor, not the rebound, so you may want to try progressively softening them up as well.
What you are trying to do it to get the front end to "bite". If everything is as stiff (including the tires) as you can get, then the front end will transfer all the cars energy to the area that has the least amount of resistence. In this case that will be the tires, or more specifically the tires contact patch or adhension to the ground.
The tire pressures will propably be the easiest and fastest way to see some improvement. Always start with the easiest fix first. Make one adjustment at a time. First, take a few pounds out of the front tires. See what the car feels like, then add a few to the rear to see if that helps the rear end rotate. Then on to the sway bars and shocks.
The 240's like a pretty soft setup to handle their best. So don't be tricked into thinking that everything needs to be low, and stiff.
Those are my comments. Hope it helps some, have fun, and good luck.


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Tristan Smith
Buffalo's Southwest Cafe
ITA Nissan 240sx #56

[This message has been edited by Tristan Smith (edited June 08, 2003).]

dpc
06-08-2003, 07:12 PM
Try just a little toe-out(1/16 or less. dave

erlrich
06-10-2003, 06:26 PM
Ben - I just want to second what Tristan and Dave have already said - keep thinking softer front, stiffer rear. Oh, and I'm almost certain the AGX's adjustment affects both bump and rebound, so you might see results if you play around there. One other comment - be careful not to get too used to using tire pressures to correct handling problems. It is often the easiest way to make corrections, but you may end up sacrificing grip to achieve the desired balance. Ideally you want the most grip possible from your tires, and should use the other suspension components (shocks, springs, sway bars, alignment) to get the right balance.

Good luck

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Earl
ITA 240SX in process