"Mentor" sought for 1985 IT-A Rx-7 builder/driver

[G-Man]

I'm looking for some wise and experienced help with my IT-A 1985 Rx-7, please. No need to get dirty or take late-night calls! Perhaps someone has built/campaigned one and wants tp help a novice create a stable, reliable car?

Building a learning platform, not the fastest car. Want to learn to be a good, smooth race driver (after time trials and track days and five races in other cars).

Car has Illumina shocks, Ground Control springs (rears look progressive - marked GCR-7RR), and does not have a Tri-Link. It was originally a "Pro7" out of California, built around 1998.

I may have to replace the shocks and may want to replace springs. Looking for some wisdom on what works well. Of course, very limited budget.

I race in Colorado - Pueblo Motorsports Park, Pikes Peak International Raceway, and the new High Plains Raceway (our pride and joy!).

Thank you in advance for the help and guidance. I promise to correctly pronounce your name when the FIA gives me the "Better than Michael Schumacher Award."
G-Man

 

[lateapex911]

Best single bit of advice to understand your car:
Call Jim Susko and buy his set up book. It aint cheap, but, the advice and science are solid and totally practical.

Some random thoughts, other than that:

• Consider a tri link setup. It makes life better.
• If going with new shocks, contact Lee Grimes of koni, mention my name. He'll set you up.
• Make sure you have a good radiator. Block the hole under the thermostat with a 1/2" NPT plug. Remove the thermostat.
• Never overheat it.
• Make sure you have good oil cooling. Ditch the beehive thing and get a real cooler if you don't have one already.
• Get a good supply of fresh air to your brakes. Use good pads like Hawk blue black or carbotechs. Balance front rear with compound or a prop valve.
• Don't rush your shifts. The transmissions are fine, unless you bang the shift or are clumsy.
• Gas tanks rust. Keep a close eye on it. Run clear fuel filters. Consider a cell.
• Make sure you send the carb the right pressure. About 3PSI. Use a Carter(?)Holley(?) pump with an internal regulator, and a secondary regulator near the carb to fine tune it. Use another clear filter just before the carb or regulator.
• You can rev it to 8, but it really doesn't breath well up there.
• Use good oil, change regularly.
• You can leave the oil squirter things in, but use premix always.
• They like good rear gears and a posi. 4.88 is a popular choice, but get a graph and figure it out for the tracks you'll run.
• Tires: See Jims book, but I run 220/45/13. other sizes can work, but think it through then stick with it, because you'll set the car up around the tire size.

• As for judging yourself in the car, don't be frustrated if top drawer ITA cars own you. On the other hand, a good RX-7 is capable of a decent finish in a tough ITA field.

Good luck!
(If you need specifics like part numbers, just ask)

 

[Andy Bettencourt]

Tires: See Jims book, but I run 220/45/13. other sizes can work, but think it through then stick with it, because you'll set the car up around the tire size.

And this is why Jake is so fast. He has his own tire size.

Great post Jake. What makes IT.com valuable. Nary a mention of a washer bottle too!

 

[G-Man]

Jake's post got me thinking: When we shave tires, maybe we should do the sidewalls?
Thank you for your help, Jake, Andy, and the folks who have PM'ed me.

I do have a good, big radiator. Will check t-stat.
Car runs the early model under-radiator oil cooler.
I've seen Jim's impressive book.
Making an airdam for brake cooling and radiator flow - have the Mazdacomp rotor ducts. Hawk blue fronts, black rears for now, with cockpit bias adjuster.
Car has the Carter/Holley pump/regulator setup. I run 1oz two-stroke oil per gallon of fuel, normally pump gas or 100LL avgas to avoid vapor lock (5,000' ASL and 100-plus track temps).
Running the Kia Sportage 4.77 LSD.
Front springs 400lbs/in, rears are 175 or 200 lbs/inch. Considering stiffer rears - any suggestions on sources?
What make/model tire do you like?
As a newbie, I wonder if the tri-link $$ is better spent on seat time and coaching?
Can you explain what you mean by "the hole under the thermostat" - is that where a temp sender used to be?
Do folks leave in the factory underhood proportioning valve?
What's a "good oil" - synthetic or not? What weight?
What are the "never exceed" oil and water temps, with temp senders mounted where?
Thanks for the help!

 

[mbuskuhl]

Can you explain what you mean by "the hole under the thermostat" - is that where a temp sender used to be?

When you take the thermostat out, you will see about a 1/2" hole. When the thermostat is open it blocks the bypass hole, by removing the thermostat you need to block the bypass hole with a 1/2" NPT plug yourself. You don't want the water to "bypass" your radiator.

Do folks leave in the factory underhood proportioning valve?

It is recommended to remove the factory prop valve if installing an adjustable prop valve in the car.

What's a "good oil" - synthetic or not? What weight?

There's a million opinions on brand. If using oil metering pump (OMP), then no synthetic. If disabled, synthetic is fine. 20w50.

What are the "never exceed" oil and water temps, with temp senders mounted where?

According to MazdaComp...

Water, taken at pump outlet, 160-195, 205 max.
Oil, taken in pan, 195-230, max 250.

There are other opinions on these numbers.

 

[Dano77]

Google bluecoilspring.com, Rear RX7 springs are 5 in by 8in tall

List is around 55 bucks or pay Susko 75+ for the red dot spring in the SSS boxes

 

[lateapex911]

And whatever you do, do NOT follow a hacks advice (on anything, really, LOL) and use that weld/glue stuff to close up the hole under the thermostat. It will break down over time, and you will chase yourself silly replacing suspect parts as temps continue to rise. However, if you find the real problem last, you WILL have a great cooling system that will keep your engine happy for years, LOL.

 

[lateapex911]

Google bluecoilspring.com, Rear RX7 springs are 5 in by 8in tall

List is around 55 bucks or pay Susko 75+ for the red dot spring in the SSS boxes

Also, they make (ISC?) cool height adjusters to help you set heights and cornerweight for the rear.

 

[howler]

The car you have is the 2010 RMD ITA Championship car. It is a proven winner in Colorado sense 2008 when it moved here. It was within 2 tenths of the PMP track record in the ice conditions of the 2009 enduro and it is capable of braking the current track record at HPR (I would be happy to break the record for you in our first race there). It is a proven commodity the way it sits. If you change the setup you won’t know if it is the car or driver that can’t go any faster. I would suggest you leave it alone until you are running the times you know the car can run. Ones you get to this level by all means make changes to suit your needs.

Currently, the only issue with reliability was due to fuel peculation when it was running 85 octane pump gas in 100 degree weather in our high altitude. High octane has cured that. The thermostat is already removed and the bypass plugged. Adding an air dam will also help keep it cooler with our low air density.

Heavier rear spring will make the car more prone to over steer. It is already leaning towards over steer as it is. The only suspension change I would make is a try-link. Even that would change the proven package you have.

Your original post said you want to create a reliable/stable car for learning on a budget. That is what you currently have. If you change it you may move away from this combo and not even know it.

 

[Dano77]

This Info changes everything. DONT F WITH THE CAR. Sounds like you made the correct choice by purchasing a known piece.

Learn to drive at the cars pace and be consistent, then change to find if it can be better or worse. Hows that for mentoring?

 

[G-Man]

Howler speaks the truth - it was his car, and he's done 1:51.7 laps on the car during a wintry Enduro while I'm at 1:58.2 (pre-excuses).

 

[Dano77]

Looks like there is about 6-7seconds just laying around somewhere on the track. Go find it.

Seriously,learn the ins and outs of this car and the guys your racing with. When we started our goal was to finish on the lead lap,then half way up the sheet. Not class,the results sheet with everyone. Then top ten and so on. probably not gonna be instant but the curve will be real sharp at first. Then its gonna level off,thats were the work really starts. That last second. Hell Im going nuts trying for a half second.

Good luck and let us know the results.

Dan 77 IT7
2010 IT7 Chump

 

[CRallo]

+1 to the above!

Learn what you have before you mess with it!

I've watched dozens of new drivers "mess" with their car and make changes spending big $$$ when the best gains would have simply come for practice in the car. Not to mention the changes made are based on things the car is doing with an inexperienced driver. Therefore, many of the conditions they are attempting to correct are often driver induced as a result of said inexperience (no offense )

If you want to spend money and tinker, buy a good data system, like a DL1, and go crazy!!!! You can get a huge tinkering fix just with the base system and the sky is pretty much the limit when it comes to adding sensors and even video... Then you get data to go over after EVERY session! Long story short, a good data system would be the best way to spend your time and money at this point! Running the same system as some of your fellow racers can help a lot too, if they are willing to share data... In the NE, those of us who have data systems almost all have DL1's and share our data freely in the interest of making us ALL faster!

Taking the changes slow will make you a much better driver in the long run. The data will quantify your changes, take better notes than anyone ever could and if you have some experience under your belt you will be more consistent as a driver, which eliminates one variable

The IT7 is a great car!!! No matter how you choose to proceed, have fun and good luck!

 

[Tim Dugan]

I'm not a mazda driver but buy the sounds of it the car is well preped. My advice as a fellow rookie driver is to put as much time in the car as u can!!! Race it, go to test days, talk to people that u race with. Some of the best advice i've gotten was from an in car of somebody elses car. Try different lines try shifting at different points. I gained almost a second buy shifting at one differnt spot sometimes thats all it takes. Keep trying ive been around the sport for 15 years as crew and 2 years ago decided to be a driver and ill never go back well id crew for anybody as long as is get to drive a little Keep asking questions cause if you dont you'll never know

+1 for dano77
+1 for jake

 

[JLawton]

Then its gonna level off,thats were the work really starts. That last second. Hell Im going nuts trying for a half second.

You ain't lyin'!!!!

I work harder now trying to get tenths than I did a few years ago trying to get seconds......

If you want to spend money and tinker, buy a good data system, like a DL1, and go crazy!!!! You can get a huge tinkering fix just with the base system and the sky is pretty much the limit when it comes to adding sensors and even video... Then you get data to go over after EVERY session! Long story short, a good data system would be the best way to spend your time and money at this point!

I can't stress enough how much a data aquisition system will improve your driving. THE best "go fast" part I ever bought........... by far!!

 

[lateapex911]

You ain't lyin'!!!!

I work harder now trying to get tenths than I did a few years ago trying to get seconds......




I can't stress enough how much a data acquisition system that is the same as other guys who will share data will improve your driving. THE best "go fast" part I ever bought........... by far!!

THE key to a good data aq system is choosing the one that allows you to compare and overlay your data...

 

[G-Man]

Just want to offer sincere thanks for the continuing help and advice from everyone. Good info here from good people.