Supra Mk3 Tuning

[Supra_Saiyan]

Hi there fellow supra owners, Im new to the forum and I just purchased my first 92 toyota supra turbo few weeks ago was wondering what are the common tuning methods for the 7m. My goal for the supra is 300whp+, I already have some mods ready for installment which are 67trim upgraded ct26, hks hi power exhaust 3in, hks fmic, mishimoto rad, mishimoto thermostat, weapon r intake, upgraded silicone hoses.

 

[jonahs_supra]

lexus afm, rc 550's, upgrade c26, afpr and safc2 will get you in the ball park of 350-400hp

of course free flowing exhaust, better air filter, upgraded fmic wont hurt

always make sure your engine is healthy and typical maintenance is up to date...belts, hoses, fluids and filters

 

[Eman14j]

Live Dangerously and shim that mothafuckin wastegate!!!

 

[87targa]

lexus afm, rc 550's, upgrade c26, afpr and safc2 will get you in the ball park of 350-400hp

of course free flowing exhaust, better air filter, upgraded fmic wont hurt

always make sure your engine is healthy and typical maintenance is up to date...belts, hoses, fluids and filters

Exactly what jonahs said. don't go past 550 on the injectors or your going to have a tough time finding a good idle with the SAFC. As stated make sure your engine is mechanically sound!

 

[7M-KDL]

Exactly what jonahs said. don't go past 550 on the injectors or your going to have a tough time finding a good idle with the SAFC. As stated make sure your engine is mechanically sound!

Did you have trouble with your idle over 550s? I have 660s in mine, I wouldn't consider mine a bad idle...just high at around 1k-ish.

 

[Supra_Saiyan]

sorry im newbie to this, what is afpr?

 

[mcammarn]

^Fuel pressure regulator

 

[xCxHxRxIxSx]

Adjustable fuel pressure regulator. Driftmotion sells a nice kit

 

[vpr131]

If you're looking to be around 350rwhp you dont need an afpr. I would just say 550s, upgraded fuel pump, and you already have the huge turbo. You might need a fuel cut defender too since fuel cut is usually around 12psi and might even be less with that big of a turbo.

 

[Another MkIII]

If you're looking to be around 350rwhp you dont need an afpr. I would just say 550s, upgraded fuel pump, and you already have the huge turbo. You might need a fuel cut defender too since fuel cut is usually around 12psi and might even be less with that big of a turbo.

NEVER use a fuel cut defender. The way it works isby reducing the airflow signal which makes the ECM take longer to hit fuel cut. This means that the ECM gets a signal for a certin amount of air and delivers fuel based on that. In fact, you are pulling in much more air, but because the FCD is keeping the ECM from seeing that, the ECM does not increase fuel delivery appropriately, causing the engine to run lean.
-AM3

 

[jonahs_supra]

NEVER use a fuel cut defender. The way it works isby reducing the airflow signal which makes the ECM take longer to hit fuel cut. This means that the ECM gets a signal for a certin amount of air and delivers fuel based on that. In fact, you are pulling in much more air, but because the FCD is keeping the ECM from seeing that, the ECM does not increase fuel delivery appropriately, causing the engine to run lean.
-AM3

and this is why i went with maft pro

 

[McGyvr]

Isn't part of the AFM and Injector upgrade a "Work Around" to fuel cut? As I understood, it allows you to get closer to 18lbs because the AFT lets more air through than the ECU realizes, while the Injectors pump more fuel than the ECU knows about. I've been TOLD that fuel cut is based on the amount of air the AFM sees.

And on the same note... I've ALSO been told that the Mazda RX-7's injectors are 550's and a direct replacement. (I hope this is right, I already have the Lexus AFM and found ONE RX-7 that still had injectors at the local salvage yard. Two more cars with injectors and I have my next upgrade! lol

I've also not seen any mention of retorqing the head gasket... First thing a newbie needs to know is Our cars don't like low oil inviroment... they spin mains quick... Second is they LOVE to blow head gaskets! Stock of 50 something lbs isn't enough. I think most of us run about 70 with ARP bolts.

And Shimming the wastegate is a quick easy way to build additional boost... but it is hard on the turbos. I'm on my 3rd CT-26...

 

[91whitepack]

I think the rx-7 injectors have to be from a turbo model. I could be mistaken

 

[jonahs_supra]

Isn't part of the AFM and Injector upgrade a "Work Around" to fuel cut? As I understood, it allows you to get closer to 18lbs because the AFT lets more air through than the ECU realizes, while the Injectors pump more fuel than the ECU knows about. I've been TOLD that fuel cut is based on the amount of air the AFM sees.

And on the same note... I've ALSO been told that the Mazda RX-7's injectors are 550's and a direct replacement. (I hope this is right, I already have the Lexus AFM and found ONE RX-7 that still had injectors at the local salvage yard. Two more cars with injectors and I have my next upgrade! lol

I've also not seen any mention of retorqing the head gasket... First thing a newbie needs to know is Our cars don't like low oil inviroment... they spin mains quick... Second is they LOVE to blow head gaskets! Stock of 50 something lbs isn't enough. I think most of us run about 70 with ARP bolts.

And Shimming the wastegate is a quick easy way to build additional boost... but it is hard on the turbos. I'm on my 3rd CT-26...

Stock 2nd Gen Turbo RX7 injectors have 2 injectors per rotor...both different CC
http://www.rx7club.com/showthread.php?t=756487

How is shimming the wastegate hard on the turbo? Only possible thing i could see being affected is the wastegate diaphram
Not to mention these CT's are 20+ years old...givin the many owners who dont know how to change oil or let a turbo cool and warm up...I'd say they hold up great

 

[grimreaper]

any piggy back system is a glorified FCD. Main difference is the piggy back will at least let the airflow signal keep rising and hopefully hit fuel cut before you do damage on an over boost. Always tune right on the edge of fuel cut. It will give you the least amount of timing the stock map has to offer. Your going to be over advanced any ways compared to a stock turbo at 7 psi.

I have adopted the cautious steps of pulling .5-1* of timing per psi above 15psi with the maft pro. Prior to this I logged hours of runs and pulls showing a consistent decrease in timing at full tilt past 5000rpms at 15psi and 11:1 afr. I didnt get my timing back to expected levels until I started doing this. Apparently I argue against the grain of most mk3 owners though. 15+psi on a stock timing map with any turbo is dangerous on pump. Everything above takes into consideration your using pump gas.

Use the timing monitor on the maft pro. You should be seeing timing very similar to the map 3P posted in the TCCS section if its setup right.

The ETPS on the maft pro is your best friend too. Nothing sweeter than having things kick into open loop at + boost so you can tune AFR.

And dont get greedy, the motor will make what it makes. Seen way to many guys go for that extra 20hp and waste a motor because of it. Enjoy what the motor makes on a safe tune and accept what the power output is. I wish I would have the first go round..

Also work your way up slowlyyyyy. It only takes a few milliseconds on one pull to end your fun.

 

[87targa]

550s, LEX, SAFC/MAFTPro (speed density) is a great and cheap starting point.

concerning 550s, i had 750s that is why i had some issues idling, just had to drop fuel pressure quite a bit to get it to idle.

timing is very important. just reiterating what grim said, work your way up slowly. it's great if you have a dyno and a way to control timing. if you can't make more power by increasing time then don't go there. i also agree with grimreaper that increasing boost on the stock timing map is dangerous. what if at peak torque you have 10* and that was safe for stock boost levels. increase the boost and 10* is not safe anymore and you can't change the timing. even better, upgrade to a laggy turbo, boost and peak torque hits at a different rpm and timing there is not where the ecu is mapped for peak torque (most likely increased timing).

 

[7M-KDL]

87targa, what are you tuning with? MAFT?

 

[Nick M]

Isn't part of the AFM and Injector upgrade a "Work Around" to fuel cut?

That is exactly it. The larger meter allows more air at a slower speed. That raises fuel cut. The larger injector makes up for the false signal.

As I understood, it allows you to get closer to 18lbs because the AFT lets more air through than the ECU realizes, while the Injectors pump more fuel than the ECU knows about. I've been TOLD that fuel cut is based on the amount of air the AFM sees.

Yes, fuel cut from over boost is based on how much air the PCM thinks (calculates) is going into the engine. I can do 18 psi with my Boss Jr 57 and the Lex meter.

 

[grimreaper]

^ to be fair, i have logged fuel cut that "wanders" a bit. I have had FC at 1400hz and then successfully managed 1900hz with out fc. Kind of a moving target we all attribute to psi alone, but thats only one variable..

with the lex afm and 550's alone, nothing over 16psi on my sp61.

 

[Supra_Saiyan]

Has anyone used a prologger before?