Basics for a 2nd gen RX7 build? [Archive] - Improved Touring Racing Forums

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Spinnetti

11-08-2008, 02:18 PM

Chris Wire

11-08-2008, 05:01 PM

Dump the power steering and go manual if you can locate a rack. Allows removal of a considerable amount of weight up front even though the steering ratio isn't the best.

I run the ISC camber plates which have a built-in mounting for a strut bar. Others use Mazdaspeed, Corksport, and AWR. All which seem to be of good quality.

Alignment settings vary greatly according to track and driving style. Post some of the tracks you intend to run and I'm sure that some of the hotshoes on here can help you out.

The one "must do" that I think everyone can agree upon is having sufficient cooling, both in radiator and oil cooler. They must both be up to the task, for rotaries are not happy beasts when overheated. A good aftermarket radiator from Howe Racing, Griffin, or Afco can generally be adapted to fit just fine, while others like Mazdaspeed, Fluidyne, ISC Racing, and others produce bolt-in style units of good quality. Some run oil-to-water heat exchangers, while others run separate oil coolers. Both will work but ultimately, the greatest effort should be made in sealing off the radiator and oil cooler with proper (and legal) ducting. The best radiator in the world won't do the job on a rotary under race conditions without it.

mbuskuhl

11-08-2008, 08:48 PM

My buddy just bought an Rx7, and I'm wondering what some of the basics are for this car? - I'm familar with the rules and general building, but specifically to this car. e.g.

Should he keep or dump the power steering?
Best Camber plates, strut bars, F/R spring rates etc?
Starter alignment settings?
Any rotary "gotchas"?

This won't be a 10/10ths car, but I do want to get him started in the right direction.

Thanks!

General consensus...

No PS
Camber plates - Mazdaspeed, GC, ISC or ? Strut bars - I just went with AWR. Spring rates - a million opinions. Here's some comments on setup - http://www.improvedtouring.com/forums/showthread.php?t=23955&highlight=camber
Gotchas- you need a 5.12 R&P, very hard to find. They are custom made and not cheap. Get the .756 5th gear. Make sure you have an S5 intake manifold if running an S4 motor (it can be done) - worth 15rwhp. Need 5 lug and 4 piston calipers. These are bitch to keep cool, you need a good radiator (AWR/Ron Davis) and will have to spend time playing with ducting. DTSS eliminators. Clip the rev limiter (there was an ad in the back of SportsCar before, might still be there) The list can go on and on.

www.awrracing.com (http://www.awrracing.com)
www.iscracing.net (http://www.iscracing.net)
http://www.flatout-motorsports.com
http://www.mazdaspeeddevelopment.com/

Good source for general info and some racing stuff on the 2nd Gen - www.rx7club.com (http://www.rx7club.com)

Personally I really like the AWR stuff. Get the ISC exhaust http://www.improvedtouring.com/forums/showthread.php?t=24938

Have fun.

seckerich

11-08-2008, 10:20 PM

Good advice so far from all. Add to the list the aluminum hood most often found on the convertible. Best camber plates in my opinion are the Speedsource parts that really cut the flex on the strut towers. Same with the strut tower brace but not sure if they still have them in stock. This car will be undriveable if you do not do at least delrin bushings and the toe steer eliminator kit. I have a few S4 and S5 computers on the shelf that have all the proper mods done. Keith Golden does the mod and is listed in Sports Car. 5.12 gears are no problem now, I keep them in stock as well as the 4.88 and a few other oddballs. Look for the factory Limited slip rear end or get the Miata torsen from the 1800 car. That should drain the bank account for now.:p

racingralph

11-09-2008, 10:50 AM

are you (or your bud) in the southeast ? if so there a few of us rx-7 racers that help him (& the car) get better. making his learning curve shorter ! so he enjoy the racing. see ya the races.

Spinnetti

11-09-2008, 02:15 PM

Thanks guys!

Its a 89 GTU, but it doesn't have the 4 pot brakes. The 2 pot ones don't cut it? (I didn't realize you could do so much part swapping with these)

So starting out, we are just looking for it to be serviceable, so from the comments it sounds like an upgraded oil cooler and radiator are the most important?
What about running the PS rack, but without the pump? .

We are in Cen-Div (Cincy area). He's just starting out, and I'm not sure I can get him to run ITS yet, but I also have another buddy looking to do ITS with an Alfa GTV (already started working on that one)... I'm in ITA now, but I might have to get an S car built to run with these guys!

Dave Burchfield

11-09-2008, 02:29 PM

Spinnetti.......if you are in the Cincy area, PM me and I will send you a phone number. I have a car you can look at.

Chris Wire

11-09-2008, 06:14 PM

Thanks guys!

Its a 89 GTU, but it doesn't have the 4 pot brakes. The 2 pot ones don't cut it? (I didn't realize you could do so much part swapping with these)

All the RX7s from 86-91 are on the same spec line so you can update/backdate any assy from all but a turbo-specific application. You've got to have the 4-piston brakes, there's no sense in not doing it as it is a strength of the car so don't pass on it. The .756 gear is great, but only if you use 5th gear (like w/ the 5.12 gear). If you run the 4.3 or 4.6 you can get away with only using 4th gear on shorter, slower tracks.

So starting out, we are just looking for it to be serviceable, so from the comments it sounds like an upgraded oil cooler and radiator are the most important?
What about running the PS rack, but without the pump? .

It's illegal to loop the rack to eliminate the pump. Change it or run it, there's no middle ground.

Spinnetti

11-09-2008, 06:19 PM

Spinnetti.......if you are in the Cincy area, PM me and I will send you a phone number. I have a car you can look at.

Dave, my friend just bought a car yesterday, so no need for that... He just wants to ease into a ITS build if the car proves sound.... Meanwhile, we have 3 (Toyota) Lemons car team we need to prep for next year too :)

Dave Burchfield

11-09-2008, 07:59 PM

Spinnetti

11-09-2008, 10:31 PM

I guess I wasn't clear or I misunderstood.......I thought your friend was looking for ideas on how to prep a car and I was offering my car as an example to look at to get better insight into what might be needed.

Ah!, sorry, I thought you meant "I can show you one for sale"... Thanks for the offer. I'll point my buddy here tomorrow and see if he can send you a PM..

Thanks....

hawke3

11-17-2008, 07:09 PM

Can someone show me in the IT specs where it says you cannot loop the power steering hoses? I looked but can not find it

JeffYoung

11-17-2008, 07:32 PM

General rule. If it doesn't say you can, then you can't. Probably the most important rule in there.

Andy Bettencourt

11-17-2008, 09:28 PM

What Jeff said. For the 2nd gen RX-7 (and any car for that matter that power steering was an option) you have to find the non-power steering rack.

Spinnetti

11-17-2008, 09:51 PM

sorta related... Can you use the washer bottle as double duty for the crankcase catch can?

Thanks...

JeffYoung

11-17-2008, 10:44 PM

Don't see why not. Is it the appropriate size? At least a quart I think?

lateapex911

11-18-2008, 10:41 AM

Yup, I run all my lines that need a home to the washer bottle. next year I'll make a divider, and toss some activated charcoal in there for environmental friendliness.

hawke3

11-18-2008, 12:21 PM

Chris Wire

11-18-2008, 01:51 PM

I don't doubt you guys at all, I am sure I need a manual rack but, I know, having been a Spec Miata driver that a looped power rack is ok for SM. Does this mean that all those guys that race both SM AND ITA/ITS with a power rack are illegal for ITA/ITS?

The SM rules specifically allow power racks to be converted to manual. No such provision exists for IT.

Therefore, if there are crossover vehicles running both SM and ITA with converted racks, I believe that they would be illegal in IT.

Andy Bettencourt

11-18-2008, 03:53 PM

I don't doubt you guys at all, I am sure I need a manual rack but, I know, having been a Spec Miata driver that a looped power rack is ok for SM. Does this mean that all those guys that race both SM AND ITA/ITS with a power rack are illegal for ITA/ITS?
Yes. That is just but one of the items that make some SM's technically illegal for IT. The 1.6's are the biggest culprit.