bikerecker

I've read the sticky that addresses the basic question of how to make the FD a relatively reliable driver. Regarding ECU and rats nest, I've been told by a locally reputable FD guy that installing new fuel pump (Walbro 485) and Power FC, along with changing to non-sequential twin control, will make the whole turbo control set up more reliable with little negative effect (besides liveable lag). My priorities are 1) safety 2) reliability for spirited recreational use, not track or racing 3) around 300 whp. I expect to change the stock intercooler to an upgraded SMIC and to upgrade the intake, in addition to the possible ECU and turbo control changes; along with the changes suggested on the aforementioned sticky.
Please impart some wisdom on this plan...
Car is a 94 R2 with 45K miles.
Thanks!

Sgtblue

iTrader: (16)

I make about 300 hp at the wheels, have basic bolt-ons, removed emissions and still retain the sequential system (mods are in my signature, I can decipher if needed). My car has been very reliable.
Removing emissions (if you're able) about halves the number of solenoids and vacuum lines.
And most important to reliability IMO is cooling. All aluminum radiator and AST (if retained). I also think you can lower threshold for fans to activate thru the PFC with a datalogit, but I installed a S5 FC thermoswitch years ago (completely plug and play) to do the same thing from 108 C to 95 C. I also use a simple (also reliable/inexpensive) boost-activated Water Injection System (WI) which provides additional cooling along with knock and carbon control.
I can't comment on non-sequential personally. Seems like it's split 50/50 between those that like it and those that are disappointed.
Though there were no known issues, I've replaced as a precaution, my OEM Denso fuel pump with a new Toyota Supra turbo pump...along with cleaning up some grounds. That pump is completely plug and play and provides a little more ceiling for my mods/power. ---> Nippondenso fuel pump

CrimsonPride

iTrader: (11)

With 45K miles I wouldn't even consider altering the turbo controls. I haven't put a lot of miles of my FD, it's right about 50K. I've had it for 8 years and no turbo control problems or issues with the rats nest solenoids.

You will probably need a catback for your HP goals, since the stock muffler seems to be the most restrictive part of the system. Also, I found coolant temps more stable w/ a straight through catback because heat is removed more quickly getting the exhaust out more efficiently. Some would say definitely do a DP also but you can run into issues with the precat removal even at your mileage studs can break off, happened to me at about the same mileage and I had to remove the turbos to extract the stud and finish the DP install project. But, still, I definitely would do the DP if I had it to do over again.

SpeedKing

iTrader: (4)

https://www.rx7club.com/3rd-generati...nners-1010998/

Zepticon

iTrader: (1)

Since i got my EU-spec i did the same, got the reliability mods down first:
- Changed the rubber in the rats-nest to thick silicone, while keeping all functions. Use quality Silicone. (or Viton if you feel rich) (remember that one of the turbo vacuum lines have a restrictor pill in them)
- Changed all coolant hoses with new ones from Mazda.
- New AST (alu if you are not on the OEM train)
- Got a new and bigger Koyo radiator.
- HKS downpipe
- Proper ducting for oil coolers
- Efini Y-pipe to get rid of the weak point with the silicone coupling.
- New fuel filter
- New serpentine belts

Other than that my advice is:
- Keep the sequential system, if you do a vacuum job, its not a big thing if you are patient and methodical. One hose at a time.
- The vacuum system is reliable as long as the hoses are new and correctly installed. The problem here is 25years old and roasted rubber.
- Don't start swapping intercooler, intakes and exhaust without a PFC.

Joe Henley

Suggestion. Have your Mazda dealer or a high reputation RX7 speed shop do the hose replacement. It took the tech guy a day to do it, but it was done and I never had to fuss with it again.
It cost me close to a grand to have them do it, but I knew the tech and talked to him afterwards. He told me about some of the "gotchas" you learn only thru experience. Thankfully, I'll never have to learn all that now.
Good luck!

Molotovman

iTrader: (49)

Great thread there. I cant believe its not a sticky.

Sgtblue

iTrader: (16)

Red95FD

iTrader: (3)

The first thing I did was buy a Bonez downpipe and I had it coated inside and out by Calico Coatings. That will lower your underhood temps considerably and that has great advantages like keeping any underhood rubber in good shape. Then I got a reliable radiator and AST. The plastic in these two will crack. Not a good thing. The next thing was a Powerfc but I kept my main cat. New walbro fuel pump, a bigger intercooler(stock mount) and a tune. I got 295 hp on a Mustang dyno and got better gas mileage. I'm guessing I gained about 70 hp to the wheels and I'm still basically stock and the car is way more reliable which is the main thing.

RW Atelier

Here's some humble suggestions from a new owner If your car doesn't come with issues need to be solved immediately, it's always recommended to upgrade the cooling as the first step regardless of your budget. The stock radiator is literally working on its limit with 255hp. The intercooler is also quite inadequate especially on the Genki (1992 or 1993 ~ 1995) USDM cars. As you may know the FD's many plastic components can easily get heat soaked in the engine bay. I always open the hood after driving to let heat escape.


My 94' CW FD had a Fluidyne Radiator and Blitz SMIC intercooler installed by the previous owner before going a full GReddy V-mount setup. They make a huge difference. I typically see water temperature about 84 °C on my PFC during spirited driving. I recommend this setup for a 300~350hp car.


There are many great threads on building a reliable car over 300hp. It's totally doable. Expect things to break though as these car are getting older and older. Once you are settled down with a better radiator, get rid of the stock plastic AST (Air Separation Tank) if you have it and change to an aluminum one. They are very prone to break. It's not necessary to run non-sequential but it's nice to swap those tired vacuum lines with new silicon ones. Always put maintenance over mods And you will have a great FD.


PM me if you want the Fluidyne Radiator and Blitz SMIC. They are just out of the car this week. I can give super low prices since I don't need them anymore. Would be nice if someone can make use of them.

Jarod R32

Also a good idea to change the hoses in the rats nest with silicone and focus on cooling like getting a catless downpipe.

trea

thanks, learned a lot in this thread.