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View Full Version : 1st Gen RX-7 Springs.What rates?



rxracer96
02-17-2008, 04:13 PM
What kind of rates are you guys running? Way back when the numbers were 300fr/175rear.Im up to 450fr/275re and Im thinking of going higher.This is with 1 1/8 front bar.I see some of you are running a stock bar.Looking for some input.Thanks

lateapex911
02-18-2008, 11:48 AM
before going higher, consider chassis frequency, and most importantly, damper capability.

tom_sprecher
02-18-2008, 12:32 PM
I'm running 350F/200R springs, 28mmF/stockR bars and Tokicos. Don't take anything I say as advice since I'm new at driving and too slow at this point but have lots of great learning experiences ahead so I've got that going for me. ;)

ddewhurst
02-18-2008, 02:07 PM
rxracer96, what are you trying to cure with your car? Oversteer, understeer?

Past 1st gener:023:

Tak
02-19-2008, 02:24 AM
400F and 275 rear. 1.25 x .188 wall front tubular bar and no rear bar. I too would consider stiffer coils (and a softer sway bar), but I am very unhappy with the quality of ANY rear spring over 200# for the Gen 1. Don't try this with Tokikos! If you have a decent spring source, I want to hear about it!

Tak
#29 ITA SFR

tom_sprecher
02-19-2008, 11:37 AM
I've heard the Tokico's are only good up to 450# up front and 300# in the rear. I need to get some more springs and play around. What other shocks and struts are available that won't cost me an arm and a leg?

As far as springs go what is the problem you have had with the rear coils over 200#? Have you tried http://www.bluecoilspring.com/?

mustanghammer
02-19-2008, 02:20 PM
Currently:

400 Front and 250 Rear
RB Front sway bar, no rear bar
Koni SA 2810 racing struts front and Pro Shocks WB735 rear
tri-link w/panhard bar

My car came with 450's front and 300's in the rear with Tokico Illumina 5's. The orginal combination was not too bad but a little rough at HPT before the repave. Also the local EP guys have started pulling out spring rate and they are going faster. A trick they learned from Tom Thrash who runs a pretty soft setup.

For my current rear springs I started with 200lbs springs and shortened them to get the desired rate. I also wanted to be able to use an ISC spring adjuster so a shorter static spring was needed. I have access to a Longacre spring rate checker which makes this sort of thing easy.

rxracer96
02-21-2008, 07:49 PM
I see my follow up post has been removed.I mentioned spring manf ect...might be why.Thanks all for your input,Ill answer what I can.My chassis frequency at Mid Ohio is some 80's station around 82.5 I think.Im running advance design shocks,super stiff cage,all bearings no urethane,trilink with my own adj. panhard,corrected front steering geometry.My complaint is the car works very well in a single corner but doing a left right or visa versa it takes longer than I care to settle.Too much body roll and pictures to proove it.I have a couple tubular front bars,install one and go up on the springs all around.Throw a new set up on it and see what happens.Thanks again for your posts.See you in the sand traps,I mean at the races.

ddewhurst
02-21-2008, 10:17 PM
Which series of corners at Mid Ohio give you your issues? "Too much body roll" Does this mean the front sticks like it's glued to the track? If so lossen up the rear for better balance. Or stronger bar in front. With the suspension do one (1) thing at a time & test before changing another thing.

Tak
02-24-2008, 03:37 PM
Thanks for the link Tom. Looks promising. Now I just need to dust off my spring rate equations to figure out what length to cut them off at!

Tak

miketrier
03-16-2008, 12:31 AM
I used to race against Scott. My 1st gen had 350 fronts, 175 rears, and the ISC tubular front sway bar, and no rear sway bar. I held the MAM track record for IT7 and the driver who purchased the car from me makes it go even faster. I wouldn't do much different with the car today.

lateapex911
03-16-2008, 01:58 PM
Misc comments:
Tom, call Lee Grimes at Koni for your damper needs. remind him of the help he gave me in Mid Ohio, and he'll get you that set up pretty reasonably. There's a neat application he has for the RX-7. If you have trouble getting a hold of him, let me know and I'll hook you up.

Advance design: To those using them, beware, there have been a lot of reports of constant nitrogen leakage...like every day. You need to be on top of that. Which is a massive pain up front. Reliability in other aspects of them has been suspect.

I think the Tokiko estimate (400F, 300R) is a tad high....