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wrxracer55 01-21-05 12:08 PM

preparing first gen for csp, looking for opinions/advice
 
i did some searching, and this is the combo that i have come up with so far for my 85 rx-7. just looking for any additional advice or opinions on this set up

-13x7 steel wheels with 215/15/13 kuhmos
-350 lb ground control front coilovers, 175lb ground control rear springs
-tokico adjustable struts
-front strut bar
-sway bars: i'm thinking of getting the racing beat matched set, but have also read that you can just get an updraded front and ditch the rear. looking for advice in this column
-panhard bar/third member: another area where i am not sure what to do. i'm looking for the best legal handling setup i can get, not sure what to do about the rear end. i've read the watts linkage binds up, and i'l like to get rid of that
-poly bushings: sway bar and front control arm
-carbotech bobcat brake pads and steel braided lines
-4.10 gear out of gsl-se
-lsd: another one i am not sure of. i've heard some prefer the open diff over lsd on these cars. i've looked at torsen and phantom grip, but have read the phantom is a joke.
-lightweight seats
-rb full streetport exhaust: i know i don't have street port, but its a nice setup
-sterling modified stock carb on modified rb holley intake manifold: i like the simplicity of this manifold
-misc other things: direct fire ignition, pulleys, electric fan, light steel flywheel, clutch, battery behind pass seat, better oil cooler

think this is it so far, i'm sure there is more i will think of. any opinions/suggestions?

speedturn 01-21-05 12:57 PM

get the G-Force Engineering Tri-Link upper 3rd link,
the G-Force panhard bar
and the G-Force front strut/balljoint spacers

get a lighter flywheel and clutch assembly

get a race carb and intake manifold

You need all of these items to take full advantage of the CSP rules; if you don't do it then someone else will take advantage of you.

Speed Raycer 01-21-05 03:20 PM

Talk to Carl @ PB & J Racing about a carb. He did wonders for my IT carb www.pbandjracing.com

wrxracer55 01-21-05 03:57 PM

pb&j, thats the sterling carb i was talking about. plan on the carb, manifold, flywheel, clutch, didn't think csp can use the spacers, and i was looking at the panhard/tri link, just wanted some reviews. thanks

slowautoxr 01-21-05 11:19 PM


Originally Posted by wrxracer55
-13x7 steel wheels with 215/15/13 kuhmos
-350 lb ground control front coilovers, 175lb ground control rear springs
-tokico adjustable struts
-front strut bar
-sway bars: i'm thinking of getting the racing beat matched set, but have also read that you can just get an updraded front and ditch the rear. looking for advice in this column
-panhard bar/third member: another area where i am not sure what to do. i'm looking for the best legal handling setup i can get, not sure what to do about the rear end. i've read the watts linkage binds up, and i'l like to get rid of that

-Find aluminum wheels if possible. Wider is better.
-Try ISC for your springs. Your #'s are about where I started with. My fronts are at 400# now.
-For the front - get 85-86 rear MR2 Illuminas.
-I have a Koni bar on front and removed the rear bar.
-My car was pretty good without going the panhard rod and tri-link setup. But to go faster you'll need it. This was my next step until I bought a completed CSP car.


Originally Posted by wrxracer55
-poly bushings: sway bar and front control arm
-carbotech bobcat brake pads and steel braided lines
-4.10 gear out of gsl-se
-lsd: another one i am not sure of. i've heard some prefer the open diff over lsd on these cars. i've looked at torsen and phantom grip, but have read the phantom is a joke.
-lightweight seats
-rb full streetport exhaust: i know i don't have street port, but its a nice setup
-sterling modified stock carb on modified rb holley intake manifold: i like the simplicity of this manifold
-misc other things: direct fire ignition, pulleys, electric fan, light steel flywheel, clutch, battery behind pass seat, better oil cooler

think this is it so far, i'm sure there is more i will think of. any opinions/suggestions?

-I use some Hawk pads (forget which variant) and have been impressed.
-With either 215/50-13 or 235/45-13 you may be shifting into 3rd more than you'd like with the 4.10 gears.
-lsd is good. From what I understand the Torsen from a Miata is better - my new car has a Torsen in it.
-lightweight seats are a good idea. Update and backdate to get your car even lighter.
-I have the RB full streetport exhaust :-)
-I have a twin 36DCD Weber set up and it stumbles in right hand turns - a serious pain. My new car has a Dellorto with a short manifold (not on top of the motor) and it's seriously faster than my Weber equipped car.
-I use the stock ignition, battery location, pulleys, fan, and a early oil cooler. I have a light steel flywheel but always wished I had gotten an aluminum one. I use a CF clutch.

Sounds like you've got a good plan except maybe for those wheels. The book that Jim Susko (g-Force Engineering) is WELL worth the $75.

wrxracer55 01-22-05 07:48 AM

the steelies i found are only 13 lbs each. do you know where i could find aluminum wheels that would be lighter? do you suggest i go with wider wheels? if so, what dimensions/backspacing/tiresize? i've been looking more at the g force tri link and panhard, and think i might go that route. with the miata torsen, don't you have to worry about not enough of the axle shaft going into the diff? i've got the 3.90 gears now, just thought the 4.10s would give a little more help to make up for the smaller displacement of the 12a. thanks

jimmdog 01-23-05 01:18 AM

Do What slowautoxr Said he knows a little about CSP. I would like to find out what is special about those rear shocks if you dont mind. Thanks, Jimmy

christaylor 01-23-05 01:27 AM

Go with as wide a wheel as you can get, more rubber on the ground is good.

Wish I could be of more help, but I've never dodged cones, except for when that fine Aggie pavement comes up and the esses become one car wide. :D

I doubt you want to put 10" wide slicks on it, but I don't think you'd be able to cram that much in there, anyway. ;)

wrxracer55 01-23-05 07:59 AM

i'd like to know about the struts also, whats the difference. i think i could go with 13x8s, anyone know what size tire i would want to run on those, and any recommendations on rims? the rims i have been looking at are the mini stock steel ones from diamond. 13 lbs ea. didn't seem too bad, but if there are aluminum ones i can go with, i'll go that route. also, i did a little more research on the rear gears, and mine are 3.90s and the gsl-se would be a 4.07, is it really worth the upgrade?

slowautoxr 01-23-05 07:10 PM

Those 85-85 rear MR2 Illuminas are the same ones that Mazda Motorsports sells as the "IT" struts. Supposedly a bit heavier duty. I think you may need camber plates with these struts. I have some old Rotary Engineering camber plates and I had to take some shim stock to form a very thin sleeve between the bearing and the strut.

The new car I bought is Wendell Karr-Ake's old car. Finished 3rd or 4th in CSP several years ago. This car was set up with g-Force Engineering stuff. This car has 13x9 Duralites with 225/45-13 Hoosier Street TD's - a very very light tire/wheel combination. (He had 13x8 and increased the width to 13x9) I asked Wendell about the 4.10 gears and he told me what I posted earlier. This car also a Miata Torsen - you're going to need this or lsd. Just get something. If you don't you'll lose tons of time smoking the inside rear tire.

Speedturn is a G-Force guy also. He road races his very cool RX-7. The balljoint spacers he mentioned are not legal for street prepared though :(

edit:
Just did a little search on the Duralite's. Looks like they may not be available in 13" anymore. Looks like you Diamond racing wheels may have to do. If you do, be sure to get the right lug nuts.

wrxracer55 01-24-05 06:32 AM

will the 225/45 work with 13x8s? i think i'll stick with the stock gears, but go with the miata torsen. thanks for the ideas, i really appreciate it. please keep'em coming.

slowautoxr 01-24-05 10:35 PM

I'm sure it'll work. I've put 225/50-15's on 15x6 wheels (GS Neon ACR). Is it the best - that I can't answer. While I get used to this new car I'm going to put my 205/50-15 Azenis on it - of course I'll have to raise it a bit to clear the tires :(

On your list you don't have camber/caster plates - is that on purpose? The best thing you can do is get Jim Susko's setup manual at g-Force Engineering.

wrxracer55 01-25-05 06:32 AM

i forgot to add them, they are one of the first things i plan on getting.

RotaryAXer 01-25-05 08:50 AM

225-45-13s work well on the 13x8 Diamond wheels.

Sticking with the 3.9 gears is a good idea. I actually considered going to that instead of the stock GSL-SE 4.07 gears when I went to 13s because I was running out of gear (2nd turning 8-8.5k rpms) on most courses. Instead I went to 225-50-13s in the rear. It helped, but I still run out of gear often. YMMV.

Sway bars: I/we (my co-driver did the work) found that you can modify the front bar and remove the rear bar altogether if you choose the correct spring rates. (you are pretty close with your first guess as far as that is concerned...400 fronts may be better) Get the G-force book www.gforceengineering.net it will tell you more than you can imagine.

Struts/shocks: The Illuminas are a compromise...they really aren't meant to handle spring rates over 300-350 lbs/in. If you have the cash don't hesitate to get the Advance Design shocks. However, the Illuminas will get you started with decent results.

Rear Axle: Get the panhard and tri-link. Again, everything else will just a be a compromise.

Just thought I would give you my input.

Travis R 01-25-05 08:51 AM

I'd skip poly bushings and go right to Delrin (Delrin AF to be specific).
Why not update to a 13b and run ITB fuel injection and a stand-alone?
I don't know your budget, but Kodiak makes pretty good wheels with CNC Aluminum centers and Al. shells. www.kodiakmotorsports.com The 13x7 Kodiaks we run are ~5lbs.
Good luck.

wrxracer55 01-25-05 11:55 AM

those wheels are awesome, but probably a little out of my budget to start. i'd like to update to the 13b, and even had a thread about it over on the 1st gen board, but again, budget. i figure if i can max out my 12a to the rules, it still will be pretty potent. i'm mostly concentrating on the suspension to start, then can move on to the engine. I don't expect to ever will the national championship in this car, so i don't want to blow a couple grand on stand alone/tb setup (plus my wife has a hard time with what i am spending to begin with, that would be a hard sell). i'm trying to stay under $5,000 total for the buildup (includes rebuilding the 12a)

scotty305 01-26-05 07:54 PM

Last weekend at the L.A. autocrosses, I talked to a guy who runs CSP. He said he took apart his steering rack and adjusted it, and was able to get all of the slop out of it. He said there are three adjustment points, though the factory service manual only says to adjust one of them. I guess the other two made the difference.

I'll try to get a lap or two in it and see for myself how it feels. I've driven in only 1 first-gen so far, and the slop in the wheel is very noticeable.

-s-

wrxracer55 01-27-05 06:34 AM

i think there is an article on mazsport about doing the adjustments to the steering

adam c 01-27-05 03:20 PM

I don't know if this is supposed to be a street car also??

You may want to consider flaring your fenders to get some really big rubber under them. If you do this, your choice of wheels and tires will be greatly expanded. I did my fender flares with a piece of 2" exhaust tubing, a cutting wheel, some bondo, and a can of spray paint. The end result looked OK, but certainly not professional. It was a good deal of work, but cost virtually nothing. I was able to fit 225/50/15 tires on 8" rims when it was done, with no rubbing. The car was severely lowered with very stiff springs in the front.

Get the biggest stiffest front sway bar you can find :D

wrxracer55 01-27-05 03:57 PM

i want to stay with the 13s to keep the rotational weight down. i'm gonna go with the 13x8 rims as mentioned previously. thanks for the ideas though

DriveFast7 01-27-05 06:31 PM

anyone know how to get a repu to auto-x fast? i think i should put in a watts link or panhard for lateral axel location since the leaf springs don't cut it :)

RotaryAXer 01-27-05 09:07 PM


Originally Posted by adam c
Get the biggest stiffest front sway bar you can find :D

I hope that is a joke.

slowautoxr 01-27-05 10:36 PM

If you're mechanically inclined and can fab up some stuff - Susko's book has some very neat ideas - including a little something on utilizing the stock front swaybar. The CSP car I bought has all the g-Force stuff on it. I'll let you know how well it works at the end of next month. How much is a front sway bar $120? Susko's book is $75 plus you get unlimited help from him.

rob81gsl 01-28-05 01:46 AM

jim susko knows his stuff up there at G force engineering. buy his book, it will really get you thinking. and he's been excellent with informational support with his products. his stuff is mainly for ITA road race stuff but is basically the same as CSP minus a couple of things like turn-in spacers.....

wrxracer55 01-28-05 07:23 AM

the book is on the shopping list (especially considering his shop is only like an hour from where i live). i will definately be getting in touch with him.


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