Dak

Quick question about rear ride height in relation to the front. I'm installing my coil overs and wanted to know where the rear height should be in relation to the front. Higher, the same, or lower. I measured all four corners before I started and none of them matched but the rear sat about 0.5" higher on the driver side and 1" higher on the passenger side. If its relevant stock spings with 330k miles on them. Stock front struts and Tokico Blues in the rear. I am aiming for 1/2 inch drop on the front in the end( the rear will drop more than that if it needs to be the same height or lower than the front).. Where should the rear set for best performance? The same height as the front or higher or lower.? If higher or lower by how much? My gut tells me the rear should be same or slightly lower. Don't laugh too hard but this is mostly from suspension settings in Gran Turismo being that way. Thanks.

Edit to add: This is more for when I make my final adjustments after I've driven the car and things settle in. My initial setting will have the rear approx. 1/8 inch higher than the front.

Turbonut

iTrader: (1)

'89 TII Factory original suspension
Measured center of front wheel to fender, middle of rear wheel to qtr. and adjusting for tire height difference.
rear 5/8" higher than front.
FYI-Both sides the same

j9fd3s

iTrader: (3)

i have a Japanese Rx7 magazine with an FC suspension tuning article by I Feelin, and they end up with the rear higher by 10mm. season to taste, but its probably a good start.
i've been meaning to post snippets, they go into really big detail. with all of the camber and toe curves and such

you want to end up with the thing level side to side, ideally fully loaded, IE with driver.

Dak

Thanks. Sounds like my original thought of the rear 1/2" higher than the front was pretty close to the factory setup but 1/8" inch lower. I did some research last night and if I understand what I read last night right raising or lowering the front or rear affects the center of gravity, I think giving the lower of the two more grip and affecting oversteer and understeer characteristics. I know I'm referencing video games again, but I looked through some of my Gran Turismo settings and most were equal but when I was lowering the rear it was on high horsepower RWD cars, so I think I was trying to add grip to the rear to counter oversteer. I also found I would raise the rear sometimes on FWD cars. Anyway, I think I am going to stay close to the factory setup and make the rear 1/2" to 5/8" higher than the front but with 1/2" of drop for now.

Dak

I've been thinking I may need to have someone close to my weight sit in the car while I take my measurements. That article sounds interesting as I'm going to get an alignment once I get my rims/tires put on and I need a baseline on where to start. Mainly with toe. Since it's a streetcar I was going to run a max of 1 degree camber in the front and if I understand correctly the rear is pretty much I have what I got since there's not much camber adjustment in the stock setup. I was going to start searching your posts as think you've posted this info in various posts throughout the years. I may eventually get the camber link for the rear so I can dial some out if need be.

j9fd3s

iTrader: (3)

i had an 87 GXL and a set of toe plates a few years ago, and i just tried some stuff. i found in the front that toe in didn't really make much difference in handling, but it felt best at zero. front camber with the stock stuff was like -0.5, which was probably good for that car, essentially the more traction you have the more the car will roll in a turn, and the more it rolls the more camber you need.

in the rear, you're kind of stuck with the camber you have, the lower the car is the more you get too. rear toe made a huge difference, stock is a ton of rear toe and it feels really stable, because it is. zero toe made the turn in really amazing, but it also wanted you to be on the throttle, which was hard to do on the street... i ended up about halfway between stock and zero.

with all of that the car felt really great. razor sharp. really light on its feet. which i find really fun.

Turbonut

iTrader: (1)

If you're looking for actual height at the wheel center, front/rear 25.375"/26.25", but that's with 215/55-16 & 235/50-16 tires.

j9fd3s

iTrader: (3)

it varies with the different models too. i've seen them at 27/28" before
mine is about 24.5/25, thinking about trying it higher. for a street car i care more about how it feels than anything else, and too low felt weird (and my tire attacked the fender)

Turbonut

iTrader: (1)

With the factory suspension unchanged, really can't see how it can change drastically, as the '89TII only has two options, leather and CD.
Actually the '91 TII is almost the same difference, 25/25.6875" but that's with the factory 205 tires, and yes, believe it or not they are the factory Gatorbacks, albeit a little square from sitting.
Not doubting you're experiences, but 2" difference is quite a bit, maybe somebody wanted a 4x4.

j9fd3s

iTrader: (3)

oh, i've measured all the ones i've had, so Vert's, the S4 GXL, etc
they vary quite a bit (the vert in the garage is really low too)

taking a step back, with the race cars, lower has always been faster. however on the street there is no faster, so IMO, how it feels becomes more important. it feels weird when its too low, to me, and it feels more like a good FC when its close to stock ~25" in the front give or take.... higher doesn't seem to really hurt anything either

Dak

Took some measurements last night when I adjusted the passenger front. I still have to readjust the rear but it looks like I am going to end up at 25" F and 25.5" R on the stock 205/55-16 tires. Lower than I started but looks like about the same as a S5 TII. Right now the rear is about .125" lower than the front and cosmetically I think I like the look with the rear a touch higher than the front.