I have a 90 GTU and I just want to know at what RPM does the VDI open and how high past redline can i go before fuel cutoff.

thanx

 

On my 1990 GXL, my VDI opens at 5500RPM. You should feel it when it opens, the engine will rev faster and you will feel a slight extra pull from your car. It also makes a whinning sound (at least on my car)

As for how high you can go, I really don't know. Don't want to get into a lean situation when the fuel cuts and risk blowing the engine.

I usually shift at the redline. My car pulls till 8500rpm with my mods.

 

I think fuel cut is at 8600 or 8700 rpms.

 

I have hit something that might have been fuel cut at 8.6-8.7K as well.

The car is not usually making useful power at that range unless it is modified . . .

 

VDI at 5700 and Rear rotor fuel cut at 8600(ish), at 8600 the cpu is hurting just to keep up, accurate timing is near impossible.

 

The ECU operates the VDI solenoid at 5200rpm, as per Mazda's info. The rev limiter is at 8500rpm, again from Mazda.

 

I guess the tach was always off. I had the solenoid harness wired to activate the solenoid remotely to opperate the VDI and activate a series of LEDs, one for the aux ports, and the other for the VDI. The VDI came online consistently at ~5600, independant of throttle position or engine temperature. Granted, Its hard to look at the tach when 100% throttle to catch exactly when it comes on.

The aux ports on the other hand would be consistantly at 3800 given more than 1/2 throttle, and engine at opperating temp. It wouldn't activate unless the temp gauge read right at its normal position.

 

Mazda says the ECU activates the 6PI at 3850rpm. Close enough...

 

cool, thanks!