[Rob_O]

Here's one that you would probably have some thoughts on, Dave, seeing as you own one of each of these cars

Since the MK3 turbo guys use the Lexus AFM as a way to trick the ECU into being happy with 550's, would it be possible to use the same idea and use the Lexus AFM to allow the MK4 NA to use the 440cc MK3 Turbo injectors? Obviously the resistor would have to be added for the low impedance injectors but the difference in calibration should be about the same

Thoughts... Anyone?

Rob_O

 

[DaveH]

This will almost certainly work... the car should run fine with 440's this way. But the ecu still won't add enough fuel under boost, so you'll have to do something about that. (maybe a rising rate fpr like the cartech ones). Interesting idea. BTW, you can get high imp 440's... so you wouldn't have to get a resistor.

 

[Kurt]

Dave, I think that some of the non turbo rx-7's had high impedance injectors. They are 450cc, would this be close enough? Would an afc correct for the difference?
Thanks a lot.

 

[Rob_O]

This will almost certainly work... the car should run fine with 440's this way. But the ecu still won't add enough fuel under boost, so you'll have to do something about that. (maybe a rising rate fpr like the cartech ones). Interesting idea. BTW, you can get high imp 440's... so you wouldn't have to get a resistor.

I don't think I'm going to disagree with you on the mixture, but I don't agree 100% either. Theoretically the system should just dump in more fuel as airflow increases, whether or not it keeps up with the demand would depend on the ECU tuning... But you do have a very valid point I had not considered. I'll put it on my list of stuff to try if I ever find a car I want to buy ( I shoulda bought the Green A/T car dammit!)

Yes, you can buy High Impedance 440s... but they didn't come stock in the MK3 so you can't buy them for <100 a set If I'm not mistakes, the plug is even the same so you just need to add the resistor in the harness at a convenient point and the rest of it looks like it should be there

Again, if I'm wrong let me know

Rob_O

 

[DaveH]

RobO: You need *lots* of fuel under boost to keep egt temps from skyrocketing. The ecu will add fuel (per the afm) as it thinks it needs for a n/a engine, but turbocharging requires more fuel.

Kurt, the turbo RX7 injectors are plug-n-play, so I would guess that the n/a ones are also... but I'm not sure.

 

[Rob_O]

Kurt, the turbo RX7 injectors are plug-n-play, so I would guess that the n/a ones are also... but I'm not sure.

Do the MK3 injectors use the oval shaped plug or the rectangular one? The RX-7 injectors I have seen used the rectangular plug while the Lexus I looked at had the oval plug injectors.

Might have to start thinking about a plan B here

Rob_O