Hi my question is if I can run the original ecu with full HKS exhaust on my RX7 FC (1991model) the engine is stock and the previous owner removed the air pump. I also have Defi pressure gauge.

Thanks

 

yes, youll be fine.

 

Thank you I ask because I read this thread:
https://www.rx7club.com/3rd-generati...ck-ecu-402931/

 

is your car turbo?

 

Yes, it is a Turbo 2

 

you can try a nice ebc to help with the boost control since it seems to be a problem. you can also install a wideband just to be sure nothing dangerous is happening. just keep an eye on your boost. youll be fine

 

Doesn’t my S5 rx7 have a ebc from fabric?

 

an external one i should say... a standalone unit like the profec b

 

ok thank you for the help

 

The issue with full exhaust and stock turbo/ecu is boost creep. The wastegate is under-sized and cannot limit boost.
It can't be fixed with a boost controller.
Recent discussion of the issue here https://www.rx7club.com/2nd-generati...uired-1155350/

 

ok I'll explain my situation better, the previous owner had installed a full HKS exhaust, removed the original intake and installed an adaptronic and brought the turbo pressure to 1 bar and as far as I know he left the original injectors. my intention is to restore the engine to an original state by reinstalling the stock ecu and the original intake but unfortunately I do not have the original exhaust.

 

With a properly tuned adaptronic the car will perform better than stock and run a lot safer. Even if you were able to make it all 100% original again, leave the adaptronic

 

update, unfortunately in Italy we do not have good rotary tuners. As a solution, I thought of buying the bonez cat and soldering it to my pipe (since it is also sold with 3 "pipes) and I read that in theory this cat allows to reach an adequate back pressure that allows me to use the original ecu.
Can anyone confirm it?

Thank you

 

The Bonez high flow cat is a good option to help control boost - and make the car smell and pollute less. On colder days, you may still need additional boost control with an open intake. At least mine did once upon a time when I owned one 20 years ago. Try it and see. I often re-installed the stock airbox and a paper filter in the winter when I lived in NY to avoid boost creep.

Reverting back to the stock ECU, you may need to reinstall the smog equipment or you might get a CEL. Not sure if you have all those parts... Also, you should check if the Adaptronic is running on the stock wiring harness or if it was customized.

The suggestion for a wideband O2 sensor is a good one. At least it gives you a means of checking whether your car is running lean.

 

I can confirm the 3" bonez cat can keep the boost under control and clean up the emissions significantly.
If I were you, I'd get a wideband 02 sensor and boost gauge. Check how the car is currently running on the current ecu and tune.
Returning to the stock ecu means going through the harness and injectors to make sure everything works. No need to fix it if it isn't broken?

 

One cold night in late November of 2006
Fairfax on ramp to I-10 West, satisfiable entry to throttle all the way open.
Glanced at my boost gauge as the secondary kicked in and it was over 1 bar, immediately let off and still managed to chip a tiny piece of the apex seal.

This was on Bonez high flow cat with RB catback, nothing else as far as power is related.

You don't want that feeling and scream Mamma mia, O dios inside your FC.

I'd leave the adaptronic(much much faster than 2? bit chip ecu from 88), get a wideband like mentioned and port the wastegate as well.

 

my problem is that we don’t have good tuner for the rotary in Italy and also we have all laws against for our cars……i just want to run the car safe and prevent it from being seized.

the current tune run at 1.1bar and also don’t burn a lot of the fuel. I already try to start the engine with the stock ecu and stock intake and it seems to run well (i check for the wire and they are in the original position the previous owner only change the o2sensor and water temp sensor; the injectors are stock)

I already have defi pressure gauge, exhaust temp gauge and water temp idicator.

The most important aspect for me is to preserve the engine and if i run it at 1.1bar I'm not doing a good job.(I also have the sohn kit).

I’m open to al the solution

Thank you all