Alignment Shops Arghhhh!!!

[240260280z]

Thanks John Just about to pour the concrete for my "shed". When I do the garage there will be 4 special square areas where I will install threaded tubes for levelling plates.

[John Coffey]

Want to know how they did it back in the day? Modify the motor mounts and move the engine to the right by 0.75-1.00 inches.

Or you can move it back about 4" like I did. Had to cut out the hood latch mount and to get the head off over the head studs you have to loose the engine and trans mounts and jack the tailshaft up a couple inches - but it did help get me a 48F/52R weight distribution.

At the end of the day, you'll never get an S30 body to be perfectly balanced unless you can physically move or add weight (likely to the right front).

And since you're already building custom engine mounts, the engine can lean to right a bit more which gives you perfect diagonals (50% on both).

[jmortensen]

No need to move components around to get the diags to match, that's what the coilovers (weight jacks) are for. It's getting the same weight on the corners LF and RF or LR and RR that necessitates moving stuff around IME.

[gnosez]

Can't say I agree with you on not moving things around after doing two race cars this year. Coil-overs get you just so far. The drivers weight is the issue and there's nothing in the right front to offset it unless you want the ride height to be so far off from side to side that folks will wonder what's wrong with your car. Moving the battery back to the front of the car would help (some).

BSR moved the engine over 0.75-1.0 inch and back just under an inch. This helped balance the car and allow the custom exhaust header to fit and not hit the steering coupler.

John to get the 48/52 we just have Pete drive the car with the seat all the way back. The delta between him and me is a good 100 lbs. We made a foam booster seat for me that allowed us to weld the seat in one spot. Nothing like having the sliding seat bracket move during a race.

[jmortensen]

I'm not sure what you guys are doing differently, but this info from Dennis Grant matches my experience pretty well. I wasn't smart enough to try and make the left front and rear carry the same percentage of weight, but I did have the experience that "a couple turns on the adjusters usually hit the target." I've probably done 5 cars total, so it's not like I have a whole lot of experience, but if all you're doing is trying to get the diagonals even, it just doesn't take a lot of adjustment unless there is something way out of whack.

http://farnorthracing.com/autocross_secrets11.html

On my Z I had the engine in the stock location and had an Autopower bar and R200 with LSD, and full interior and I came up within 20 lbs or so of even crossweights right out of the gate. Made a small change to one corner and I was within 5 or 10 lbs IIRC, and had 49.5% weight in the front. For my rebuild I moved the fuel cell as far to the pass side as possible and will move the engine right as well. That makes the corner weights more even, but it doesn't make the diagonals easier to adjust, at least in my limited experience. My buddies 510 which weighed something like 1800 lbs + driver of 225 was really left side heavy, but getting diagonals correct required about 1/4 turn on the rear weight jacks that he had installed. I think that was the very first car that I was present for weighting (his too) and we were looking at it like: "That was it?!?" I did a 911 once that was low on the LR corner and we didn't want to mess with the spring plate adjustment to raise that corner, so we tried to jack the weight around without it and ended up with a balanced car that was close to bottomed out on the RF corner IIRC. Got it done, it was a real bitch, the boss looked at it, and said: "Start all over. Adjust the spring plate first, realign, then corner weight." That was not a happy day for me, but it corner weighted out with very little trouble the second time.

[TomoHawk]

From my experiences with alignment shop, they will only try to get things to be "within specs" which means plus or minus so much from being perfect, even after giving them an order and a print out of what I require for the S30. they just look up your vehicle on a computer or in a book, type it into the alignment machine, and start (banging and twisting) things under there until you hear the beep and it's "done."

If you really want things to be perfect, you need to find a custom shop, not an "alignment shop."

Edited November 11, 2012 by TomoHawk