Hey everyone, I’m Josh. I’ve been a member here for years but this is my first real post. I always felt like my build wasn’t “post worthy,” but I’m ready to share where it’s at now.

I bought my 1993 Mazda Rx-7 in 2007 after it had been totaled from an accident. It had some body work repairs done, but it later sat outside for years. The engine and transmission were not usable, so I started with a rolling chassis. I took that opportunity to try something new (at the time).

Right now I’m not doing a deep history post, just sharing the current setup and looking for feedback from people who’ve been around swaps and turbo cars. If there’s enough interest, I’ll put together a proper history/build thread with the full timeline and the “why” behind my choices.

Current setup:

• LS2 based built engine
  
• Single turbo (Garrett G42-1450)
  
• Link G5 ECU + custom wiring harness
  
• Tremec F Mag 6 speed + SPEC dual disc clutch
  
• Kaaz 2 way diff + upgraded axles
  
• Coilovers + big brake kit
  
• Pump gas and E85 tunes
  

I’m happy with where it’s at, but I also like that there’s still room to grow.

A couple questions for the group:

1. Any “wish I did this sooner” reliability modifications you recommend for a street-driven setup like this?
   
2. I live in Arizona and fight summer temps. The main radiator wasn’t enough in the hottest months so I added a smaller secondary radiator. It helped, but I’m trying to do this the right way. For people running large displacement turbo cars in hot climates, what actually fixed your heat issues long term?
   

I also put together a quick walkaround and hood reveal video. If you want to see the car and hear it, here it is:
See the car

I’m not here to start a rotary vs swap debate. I like both. I’m just sharing what I built and hoping to learn from people who’ve been down this road.



The car today

The engine today

The car back in 2007

 

what is the front and rear weight?

 

Hi,

I unfortunately haven't had it on scales so I'm not sure.

 

That intercooler is seriously blocking the radiator. Is it at least ducted in the front?
To help with cooling on my LS9 turbo FD we added a secondary radiator out back behind the fuel tank which helped tremendously as I believe you did. My intercooler is also a Treadstone but its only about 3.5" thick I believe. In the 1/4 mile the IATs are good on e85; however on 1/2 mile runs it gets toasty and some water/meth injection would help. An a/w intercooler intake style intercooler would solve a lot of these problems.

 

The intercooler goes up to my bumper and I have weather stripping sealing the front. My issue in the 105+ summer days is at idle, not when I'm moving 50+ so I'm not confident any more ducting would help.

Are you able to share pictures of your secondary radiator? Mine is a small one I mounted in the passenger air duct.

I really like your setup!

 

It is mounted behind the fuel tank at an angle to get air... but it isn't even ducted. My guess is that it is 8" tall x2" thick and smaller than the width of the fuel tank to clear the exhaust. In 95* non humid weather we could do 1/2 mile passes (195-198mph) and after the pass it would go to maybe 210.... but then quickly get back down to about 185* driving back to the pits. The front radiator is probably 4" thick and the lines going to the back are -16AN lines with the main run being made out of aluminum which allows a lot more capacity as well. I would try the secondary out back at the fuel tank... or you need to redo your turbo setup and focus on cooling as a priority and not the other way around.

Make sure you use a vacuum pump on the cooling system to properly bleed it. These can be a **** to get the air out and cause all kinds of headaches. I run distilled water, Redline water wetter, and a splash of coolant to prevent corosion.

 

Only problems at idle? two of these will fix that. These pump out more than any brushless or similar sized fan. These are actually insane
https://www.summitracing.com/parts/s...RoC1NcQAvD_BwE

 

I hear you on that! Doing it with a vacuum is a game changer.

Thanks for sharing! I think I can fit two of those, I'll just need to make a new shroud.