marks gt

Ok

Just maybe something stupid I am overlooking

89 gt murf supercharged kit 42 lbs injectors low boost

New mass air
good vacuum
good fuel psi
air/fuel in ratio

Basically car runs well under light throttle anything over 1/2 just lays down
if I change the plug gap down to .020 from .032 the car runs pretty good and makes some power.

Tim thinks that the airflow over the maf is causing some issue.

John Speake

You have his air restrictor in the MAF ? And Tim's chips installed ? (I think the low boost version now has custom chips, like the stage 3)

marks gt

Yep. I have the high boost set-up without intercooler. Making 5 lbs at 5000 so far.

John Speake

I have heard of some airflow turbulance upsetting fuelling at idle/low loads, but nothing like you are reporting at higher loads. Certainly sounds like something blowing the spark out.....

SeanR

Do you have any rubber/silicone intake tubing on the suction side that could be collapsing?

marks gt

Found it. Ignition module failed. I was suspecting that might be it, but it was one of the few parts I did not touch.

tda1

Marc how did you run your vacuum hose for your boost gauge?

marks gt

I just put a temporary tee in by the mass air meter. No hood and guage is taped to the windshield wiper. It was just for testing.

tda1

Very cool. I'm very pleased with my MURF setup. I have the intercooler too. Tons of power. Not good on tires.
Its running a little hot lately but I think my thermostat might be taking a dump. I went weeks with no issues other than setting my fans up backwards.