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Need help determining ride height- Please help...

Old 10-28-2001, 11:55 AM
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WOW! That's pretty messed up... I was aware that there are many variables that will affect these kinds of things, but damn... I knew the flat surface thing was important, as I can SEE a difference on slight angles. I mean hell, cars are heavy- you can shift an extra 1600lbs towards one direction, and even if onyl a fraction of it goes that way, it still makes a differece- I saw the whole thing lower when a friend climbed in the other day- I may try to get some mearsurements this way

Anyway you said the radius was 11.5" and 11.7" (f/R)- this is really strange. I know about the static loed thing, but a standard 245/45/16 is 24.68" RD, or, 12.34" radius, and you have taller tires too... What are you running again BTW? I think you said you had 17's, so is it a 275/40/17? I remember talking w/you awhile back, and we came to the conclusion you wer 1" tall, so that sounds right, as a 275/40/17 is 25.66". What does your's run at 80mph or so (rpm's)? Do you have any specific #'s you're aware of for 5th gear?
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Old 10-28-2001, 12:17 PM
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Originally posted by Robby:

What type of spring rates are you runnig? 25.5 t-bars just sound kind of small(?)...
Does that sound like it would work???

Thanks, Robby</STRONG>
my 25.5 bars are from a M030 car. The stock 86 Turbo has 23.5 bars. I have the M030 front springs. They are about 175lbs depending on who you talk to. It actually made a significant difference. However, I'm now looking for more spring rate in the back (and front).

Your choices should be good, I'm not sure of the balance of the 250 springs to 27mm bars. I've heard of guys running up to 350lbs on the front with those rear torsion bars. But like I said, I don't really know.

Be aware the rears are a bear. You'll probably have to do them at least twice. Know that going in and it won't hurt so bad..

Good luck.
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Old 10-28-2001, 12:30 PM
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Robby, I edited my post a little so you may want to read - I put in the extreme measurement differences at different spots in the gas station. And this was a Holiday gas station, not some cut rate that had his drunk brother-in-law pour his concrete pad.

Tires: yes you recall correctly from our phone conversation. I have 275/40/17 on rear. And you are correct that they have a 25.7" diameter, however, Bridgestone says the static load radius is 11.7" .... which is quite a bit smaller. I think if you get rolling fast the radius would move up larger due to centrifugal force.

As far as speedo, I haven't really thought too much about this until yesterday when I was taking your dumb measurements. I'm about 4% off stock per Bridgestone's revolutions per mile - which seems to relate to my real world experience on highway. But I have not run a speed trap, GPS, mile markers, etc., with this setup. And I haven't spun the car up to top end with this rubber since I got nailed so bad the last time I got caught doing that on the highway. So I don't know if I have changed the ratio too long legged to bog things down and cut top speed.
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Old 10-28-2001, 02:17 PM
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OK, upside down with my tounge hanging out gets the following:

LF 24.5
LR 24.75
RF 24.5
RR 24.75

All four corners could use some air, so I'd figure around a quarter inch increase with the correct pressure. The earlier figures I gave on the LF were incorrect - seems I read better upside down that rightside up .
Still lookin to raise the rear a bit. The stocks are OEM with 75k on the clock. I'm hoping to get a bit more height with new shocks - but there seems to be some disagreement about the amount of increase amoungst those I've talked to. Some say none at all as the springs are supporting the car at rest, but I kinda expect some increase because the current shocks are shot. What do you guys think?
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Old 10-29-2001, 02:44 AM
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Thanks guys... oh, and Mr icat- I hope you don't have a headache (or even worse, a tongue ache...)!

Not sure about the spring thing, but if the original's are really worn out, then it might be, but I wouldn't expect much. Many people say that adding helper springs raises the rear slightly, and that the t-bars may need to be adjusted. BTW, I had a 1st Gen '89 Integra that I installed new Tokico 5-way adj shocks and Eibach springs when the car had 150k. I didn't get a chance to upgrade the t-bars, as I was run off the road before Mugen got them to me (back order). Integras had t-bars on the front w/springs in the rear. Those cars always had too much gap b/t the tire and fender. That was one reason why I wanted the new springs. It really needed to be dropped about 1" all around, and that's what the Eibachs were supposed to do. By the time I did the work, though (150k), it really only dropped the rear down about 1/2". I did notice, however, that the front end seemed to bow up b/c the A**holes that did the work, "didn't know how to adjust the torsion bars"- I took it elsewhere, and watched (helped) as it was being done- it was about the easiest thing in the world to do. One nut on each one, several turns each... We did lower the car, and drive it around for several minutes- two different times I believe (while it settled)- but it stayed fine after that afternoon. It took a total of no more than 45 minutes... It sounds like 951's must be different, though. Anyhow, part of the reason for this story, was to point out, that the rear lowering affected the front in the opposite way, AND, I'm sure the springs would have reduced the height by 1", BUT, the car was old, and had started to sag a little (1/2" maybe- the shocks could have had a little to do w/this, but I'm not too sure.
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Old 10-29-2001, 07:13 AM
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As promessed:
Car is Euro spec '86 951, standard and no major colision damage (to my knowlege).

L-F: 645 mm (25,39 inch)
R-F: 645 mm (25.39 inch)
L-R: 658 mm (25,91 inch)
R-R: 656 mm (25.82 inch)

Tire size front 205/55R16 - rear 225/50R16
Tire pressure 34 PSI all 4

Front clearence 131 mm (5.16 inch)
Measured at the lowest point of the (black)"horizontal" plate attached to the spoiler (don't know the English term for it), in the center about 2 inch behind the fastener.
The plate below the engine is a bit lower though, estimate: 1 inch max, cant get at it now.
Measurements are taken on a perfect smooth and leveled concrete garage floor.
Hope this is of help
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