View Full Version : Live axles and LSD's.
ottocycle
10-17-2007, 07:20 PM
Hello all,
I noticed that nobody had posted here for a while so here goes. See my little blurb in the wanted section.
I think my car needs an LSD. She has snap oversteer when try to exit a corner under power. I have a Ford Escort live rear axle and would like to get a Quaife ATB LSD or find another axle that I can make work. I am thinking I might like taller gearing as I am running out of wind on the main straight at Summit Polnt (my local track). Does anybody have any suggestions as to what type of diff I should look for and what rear axle I should consider. Any suggestions as to what else could be inducing this condition would be appreciated. I had extra weight in the car (an instructor of about 180lbs.) and my shocks were set rather firm. I will be on the track again next Saturday and will set the shocks soft with zipties on their shafts to make sure I am not bottoming them out.
What do you think?
Cheers,
Dermot.
Fury/Hayabusa.
slngsht
10-17-2007, 07:46 PM
Dermot, just to clarify, you have an open diff now, and when you put the power on coming out of a corner, you oversteer? If that's the case, any kind of LSD will make that condition worse.
R1 Seven
10-19-2007, 04:50 AM
I would certainly soften the shocks in the rear. Really, the shocks should not be used to keep the suspension from bottoming anyways. Conversely, you may want to increase the damping on the front shocks as an experiment as well. You may have tried this already, but adjusting driving technique may help as well. I know in my car, I have to ease into the throttle gradually coming out of the turns to keep from spinning the tires as much. Our cars are so light, they get a little nervous at times.
I am not sure if you have driven on the new pavement at Summit Point yet, but I did last weekend and it is nice and smooth with plenty more grip. The car will probably drive different just because of that.
Kitcat
10-22-2007, 09:35 AM
Tried stickier rubber?
sporqster
10-22-2007, 11:42 AM
I found that a lot of my oversteer was coming from sloppy rubber bushings in my trailing arms, causing the rear end to go into 'four wheel steering mode'. I changed to rod ends with poly races (along with fatter, stickier rubber) and now the car handles much more neutral and predictable... maybe even pushs just a little on track-out.
I'm using an Alfa Romeo LSD.
ottocycle
10-22-2007, 08:30 PM
Thanks guys for the feedback, keep it up.
You are all partly right , I think. I was back on the track last Saturday driving solo with a few changes. Because of that I cannot definitively say what initiated the improvement. I backed off the shocks to full soft and dialed in more pre load on the front. I ran with tire pressures of 17R 16F. The car ran better but still needs work. I was able to get it to slide a little but it felt like it was on marbles. It was not a comfortable slide and I did not let it happen often. It had rained Friday night and the runoff was wet and muddy. I did not want to be the one who trashed the racing line! I changed my driving style in that I was very gentle with the gas pedal. I am thinking my tires are limiting me. I have Falken Azenis 195 60 14 on her at the moment and I cannot get any heat into them. I would put my hand on them after a 20 min, track session and they would feel barely warm, on a par with body temperature. Theh should have been a lot hotter. I think my choice of tire was bad. I believe the tire is great it is just not soft enough for a car as light as mine (about 1,350 lbs). I willl put them on my Alfa this spring and look for another. (Any suggestions).
I think if I can find a soft 14" tire I will put a slightly wider one on the rear, perhaps 195 front 205 rear. I happen to have an Alfa rear axle and it has an LSD among my spares stash. I might re engineer things this winter and fit it. My rear bushings are good.
Thanks all.
Dermot.
Fury/Hayabusa.
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