Track Days HPDE & Autocross setup
 

I have had my Rx-7 for almost 9 years and have enjoyed it thoroughly. It was daily driven for 7 years, and now that it isn't my daily driver I want start tracking it. I have done the first two Autocross events for this year in the 7 and it was great.

I'm not new to autocross or the track, I just have never used the Rx-7 because she was my baby (still is). I usually do at least 2 track events during the year, and about 9 autocross events. This year I want to start using the Rx-7 and I want to start setting it up. Here is a list of what I have done to the 7 so far.

'94 R2 160k on chasis
Mods:
Pettit rebuild with 60k miles on it
Fluidyne radiator
Pettit 2 intercooler
Aluminum AST
Intakes
racing beat exhaust
downpipe
Apexi PFC
Walbro fuel pump
Tein Flex
Probably a few other things I can't think of at the moment

I also plan on buying the Stoptech Front Big Brake kit with a set of Enkei RPF1's before the track day as well. I decided on 17 for cheaper tires.
Fronts: 17x8.5 +40 offset 255/40
Rears: 17x9.5 +38 275/40

I want to make sure that I'm on the right track for getting my car setup to be fun and competitive. My biggest concerns right now are cooling. Will the stock oil coolers be enough for a full track day?

AM I on the right track to get out on track? What should I be looking at to do next?

There are a lot if threads on this, hopefully some of the fd road racers see this.

Are you aiming for any class in either autocross or road racing? Figure that out first, it sucks to have to uninstall parts to get legal.

Also, you wheels you're buying are too narrow, wheel width matters as much as tire width, I'd run 17x10 square with 275s if you can fit them. It's almost the same price and it'll be a much faster car

I'm not looking to be in a certain class for autocross. I just like competing with my friends, and we are all in different classes.

I have been doing a lot of research lately to figure out what I should do next. I read a great post/thread that said the 17x8.5 would fit the Stoptechs, but I can do a little more research to see how much wider I can go. I don't want to roll the fenders.

You're definitely going to want big dual oil coolers for track sessions in FL.

FWIW with wheels, I run 17x8.5 +48 and 17x9.5 +42 with 255/40 and 275/40 NT-01s on the track. The rear definitely had to be rolled to fit the tires as they're pretty wide, my fronts were already rolled. I'm running a bit different offsets than you, but I still think you'll need to do at least a mild roll. The tires are a bit "squished" on the rims but nothing dangerous and it doesn't seem to affect turn-in on the car.

I've never run the Stoptech brakes, but your main concern will be pad choices available as there are limited pads for the rear of our cars. I run Hawk HT-10s now and have a set of Hawk DTC-60s ready to go on this season. If you prefer other brands make sure you check that you can get them for both the rear and for the stoptechs.

DO NOT buy staggered wheels. The car will push or you will find yourself doing crazy things to the car to keep it from pushing and nothing is worse than trying to dial out a push. It works well for beginners on a road course but it sucks and or blows everywhere else.

I'd recommend going with 18 x 9.5 or 10 wheels of some sort that are light weight with 44mm (9.5 wheel) to 50mm offset (10). Yep 17s are less expensive but the tire choice, fitment and handling are not as good as an 18 inch wheel.

Buy a tri point front bar and leave the stock rear one alone.

Get the in tank surge cover (can't remember who makes it)

Get a HF cat or midpipe (if no airpump) which will significantly lower your exhaust temps but try to keep the boost down. I used to unplug the wastegate and pre control solenoid and run off the spring and the boost would creep to 10 or 11 psi but stayed in the 7 or 8 psi range the majority of the time which helps with temps.
I've said it over and over again but you don't need power to go fast or be competitive on a road course in this car because the proper entry and exit speeds will make up for those heavy high HP cars you are on track with.

The Stop tech kit is great for the $$$ and I'd recommend using Hawke DTC 70 front 60 rear (stock rear brakes are fine).

As time goes by and you get faster and faster you can do all things we all end up doing:
VMIC
single turbo
rolled fenders
bigger stickier tires
better heavier spring coilovers
big wing
etc..etc...

However the above changes with good ducting is all you need for next few years to have a complete blast in the car :icon_tup:

Smokey The Talon:
I will definitely be buying an upgraded Dual oil cooler kit sometime this year. I was hoping to get through my first track day on the stock oil coolers, but I always want to be safe, rather than sorry. Have you ever run on track with the stock oil coolers?

I love Hawk pads, so I'll have to check to make sure they work with the Stoptechs. I have used Stoptech pads before and didn't like them as much as the Hawks.

I was hoping to get away with not rolling the fenders, but it looks like that isn't really an option. I'll definitely go with a square setup and look at 18's for the RPf1's. Will I still have to roll the fenders?

For the sway bar I was going to buy the Tanabe because I can get a good deal on a brand new set. I'll start with just the front.

As soon as I'm done with this post I'll start looking into the In-tank surge cover.

I do have a straight pipe in the car, that is one of the things I forgot to list. I also have the 99 spec twins. I'm with you on being quick through the corners. Straight line speed is easy, it's the challenge of getting a great track out and carrying the speed out of the corner that I love. I'm with you on that one. Unplugging the wastegate and pre control solenoid is not something I have done before. Is it ok to do even though I have a tune with the PFC?

I would recommend rolling the fenders period. You want to remove the chance of grabbing the fender and tearing up your tires during high performance driving.

I use the Tanabe bars and they work well. I think you'll like them a lot with your setup.

I think they are still available:

RS Engineering - Fuel Control and Specialty Parts for your 3rd-Gen RX7!

I've never run with stock oil coolers, but it doesn't have to break your bank to get dual oil coolers. Check out Howard's cheaper method for dual oil coolers here:
https://www.rx7club.com/3rd-generati...-cheap-633480/

I think that the above setup would still be good insurance for temps on the track compared to one stock oil cooler.

I don't want to run into that problem on track. I'll do what needs to be done to be safe. I just worry that it will look odd when the fenders are rolled.



You made that too easy for me. Thank you! Just bought one.

I started looking around at a few of the DIY dual oil cooler threads. I think that is a good place for me to start.

The R2 coolers are fine if in good shape you may consider having them reconditioned but you don't need aftermarket oil coolers.

Your biggest temp problem will be intake as long as the oil coolers and radiator are ducted well.

Quick easy fix on the intake/charge temps would be water injection.

http://mahjik.homestead.com/files/FD...opeka-1144.jpg

It's not something that stands out... My fronts are rolled above.

+1

Spend the $ on a v-mount setup before larger, dual aftermarket oil coolers.

I found a thread that talks about reconditioning the stock oil coolers. American Cooler service is the place a lot of people were using about a year ago. I'm going to send an email and see if they are still open.

I started looking into the water injection. I've never looked into that so I have a lot of learning to do.

That makes me feel a lot better. Your car still looks stock with the fenders rolled. I guess I don't have to get anything too aggressive.

Do you use the stock wheels for track days?

Funny thing is I actually have a Rotary Extreme Monster V-Mount. My buddy went from a single setup to a LS. It was a long time ago when the plan was to go single. Things changed and I ended up keeping the twins, and never put the V-Mount on, thought it would be overkill. I've had it in the garage for far to long, waiting for the day I go single. Looks like I might need to dust it off and see if I can make it work with the twins.

Yes, I use the stock wheels with Victoracers at 245's. I'm looking into moving towards Diamond Racing wheels for some custom sizes:

Diamond Racing Wheels

https://www.rx7club.com/suspension-w...2/#post8286360

Hey Jerry, did you ever hear from American cooler service? I've been taking notes from all the advice given to you.

Adam

Yes. They emailed me right back and said they could help. I'll be sending my oil coolers to them in a few weeks. I'm moving soon and don't want to start doing any anything to the car just yet. Not until I get it settled into it's new place.

I have just been going through the forums like a mad man planning out the next few things.

Awesome, I'll ping them for a quote as well. Good luck with the move! I also hate moving.

Adam

I think I'm going to order the RPF1's in 18x9.5 all the way around. It looks like the +45 for the fronts will clear the Stoptechs BBK, and +38 for the rears will be sufficient.

What size tire should I be running?

Fritz - why do you recommend the tri point bar? It comes in .097", .188", and .25" wall thickness, which would you recommend?

My 94 still has 100% stock suspension all around and I too am piecing together a track worthy set up to start my track day addition. Is there a path you could recommend for logical upgrades?

After going back and forth on wheel size I finally got a set of Enkei RPF1's. I got a good deal on the 18 +45 and +38. Now I just need to get some tires. I hope they make the Hankook RS-3's in the size I need.

The Stoptechs are in and waiting to be put on. Same with the Rotary Extreme V-mount setup. I should be getting in into the shop sometime late next month. I'll need some custom piping made to fit the twins.

I like the tripoint bar because it's adj.

I'd go with the .188 wall which is what I use. Mine is set in the middle and it's a 5 position bar so I can move it 2 spots softer or 2 spots stiffer. When I got the car it was 1 spot stiffer but I felt it was pushing a bit on entry.

I feel like the sway helps the car take an initial set for the corner but of course springs etc... also make a huge difference but those aren't easy to change so this is why I think it's great to have an adj bar. You can of course also influence the cars behavior with the shock settings but I feel like that's more of a mid corner thing.

Do the same offset all around and get 5 or 6 so you have a spare in case

^The wheels have already been purchased.

Is there a difference I will feel in the offset being different from front to rear? I plan on running the same tire size all the way around.

Spare wheels? You've had extra wheels this whole time?
http://content9.flixster.com/questio...695459_std.jpg

I bought a Triple gauge speaker pod and now it's time to put something in them.

I was planning on running...

-Oil Temp
-Oil Pressure
-Water Temp

Finally got around to working on the 7 again. Oil Coolers have been reconditioned and Stoptech BBK installed.

I need tires for the RPF1's. I got a square setup finally 18x9.5 +45 for all four corners. I think I need tire size 255/30/18. I believe this will work if I roll the fenders.

I don't think a tire exist in that size. You'll likely need to go to 255/35/18, which is where you'll have a ton of options.

jerry i have the exact same wheels, and i have 265/35/18 tires on them (bridgestone RE-11). i recommend running this size. 265/35/18 is a pretty common size, you can rotate the wheels front to rear (and left to right), they look nice, and 265 is a lot of tire, so the grip is great.

you will need to roll the front fenders, but the front wheels/tires fit very nicely after that.

https://scontent-a-dfw.xx.fbcdn.net/...76388009_n.jpg

https://fbcdn-sphotos-g-a.akamaihd.n...34049379_n.jpg

front wheels (about 1/4" of outside clearance)
https://fbcdn-sphotos-g-a.akamaihd.n...81041121_n.jpg

rear wheels (about 1" of outside clearance)
https://scontent-a-dfw.xx.fbcdn.net/...35883689_n.jpg

Thanks for the info. Tires have been ordered. I went with the Dunlop Direzza ZIIs. I have been using Hankook RSs for years and decided to try a new tire.

Which rear bar do you use? Front & Rear spring rates? Whatever you use, with your skills, you haul ass on the track! Really enjoy your videos.

For the track, I just added race pads and Eibach hollow bars for the summer "season". The front bar was like the tripoint at mid setting, with .15" wall. This is an old table I made, still relevant for Tripoint, RB, and stock:

http://www.rx7.org/Robinette/antiroll_bars.htm

.

Bars, Part 2
 

OP, for the track, I just added race pads and Eibach hollow bars (discontinued) for the summer "season". The front bar was like the tripoint at mid setting, with .15" wall. When I started to run the hollow 19mm rear at the stiff setting, I cracked the rear bar along the straight length. I wondered why I was starting to understeer badly. I modified/stiffened the oem front mounts before any option was available.


This is an old table I made, still relevant for Tripoint, RB, Suspension Techniques and stock:

Antiroll Bars

As Mahjik said, you need to know MR's and other info to technically size bars. One simple guide is to maintain the same stiffness ratio, F/R, as the diameter is increased, if you want the same balance.

.

Finally got her on the track yesterday. Everything went better than I wanted. I ran the 265/35/18 and had lots of grip. The car was balanced well, but tended to understeer more than I wanted. I got the Stoptech Brakes put on but did not realize I needed to change the Brake Master Cylinder. I will be looking to upgrade it now.

I will post pictures and videos soon.

for a first time out, mild understeer is kind of a pleasant surprise. it lets you concentrate on other things, besides getting your elbows over your head :)

^ I'm with you on that. I'll get around to tuning the car to drive like I want it. I have the Tein Flex Coilovers. I have no idea what to do when it comes to things like rebound and dampening though.

The highest water temp I saw was 113c in traffic so I started to slow down. Fresh air it was sitting at 104c which I thought was good.

Beautiful car Jerry, did you repaint it?

My 93 suffered from some chronic paint lift off in small spots. And from Summit Point Raceway, the paint in front got peppered from small gravel on the outside of turn 10. I was chasing a friend and we both stepped out a bit on the 95mph corner, but I was the one that got the sand blasting. :(

.

yeah man that car really went well ! , I think I wussed out , I would just let off a soon as I saw 105c

well regardless , Next event ! I plan to keep up with you haha

Still has the original paint. The pictures make it look prestine, but she has her blemishes. I have the clear bra on the car so I didn't get any big chips that I know of. I have yet to give her a wash and see fully.

You may have been right to let off. It's been so long since I've been on track. My adrenaline starts pumping and I just have to keep it going.

there was another FD on sunday , and he was going into the teens as well .
:icon_tup:

I mod'd my eom water temp gauge (parallel resister) to start rising quickly at 105C. I had the Ron Dennis Rad with a well sealed supply of air, and dedicated air to a greddy SMIC, custom air path to intake ( my Touring has one oil cooler, so other opening was my air intake ).

At the track, I would only see the gauge go above 105C on the hottest days, and all I had to do was short shift a minute to get temps back down.

With your dual OC's, you should have better cooling. I put 1/4" screens loosely in front of my single OC to keep the fins open for max airflow. Did same for Radiator.

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I plan on adding a water temp, oil temp, and oil pressure gauge. The modified OEM Water temp trick is something I'll look into.

For the Oil Coolers I need to find the 99 spec ducts since I have the replica 99 front end. That or I can make my own ducting, but I don't know how. If it comes down to it I'll figure something out. Like they say necessity is the mother of invention.

If you are adding a set of gauges, then I don't see the value of modifying the stock gauge, other than turning it into a warning gauge as the needle moves quickly aabove 105C.

I just wanted a boost gauge on the A piller. Instead of a 5 point harness, I got a universal lap belt, bolted the anchor ends together, and fitted it around my waist just before a lapping session.

I did a write up of my parallel resistor method (archives?), and another guy figured out how to modify the internal gauge circuit to make it a linear response.

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