Fast EZ EFI HELP please!
 

So I finally have my GTO convertible running but not well! I've built a stroked out Pontiac 400 to 463, engine dyno runs showed the the motor put out 520 hp and 613 tq with a carb. In the car I am running FAST EZ EFI and a 4l80e transmission. Now here is the issue, I have driven the car around for a while enough time for the computer to learn but it's not! If I am driving around the car runs great but when I hammer down on it the car falls on its face!! I'm losing at least 150 to 200 hp some where and I can't find it, can this system be tuned any other way? I NEED HELP PLEASE!!!!

Sorry to hear you are having problems. However, I think you need to give us quite a bit more info to try and help you figure this out. Some things that come to mind first are your fuel system. The ability for any efi system to perform relies heavily on the fuel system's ability to maintain the correct flow and pressure. So how about some details there? How is timing being handled? Also, more details on the transmission, what converter, what computer, how has it been tuned?

With this info, some folks here may be able to lend a hand.

Just one more question, have you called FAST yet?

When I purchased the EFI system I bought the complete kit with the fuel system from FAST, the transmission is a pheinox 4l80e compu shift computer with a 2500 stall.

The kit a friend bought had a carb fuel filter instead of an EFI one; had the solid block phenolic insert in it instead of a screen. Super restrictive and the fuel pressure dropped like a rock under load. Also the pump started getting louder after cruising for a bit.

You might want to check yours, because that was the supplied filter that came with the complete kit directly from FAST.

I will do that first thing in the am, thank you I never even thought to check as for the pump its still ok

The Fast supplied pump is an external pump. Have you noticed if you have this problem with a full tank of gas? Sometimes the stock in tank pick-ups will uncover under hard acceleration and starve the pump.

Along with what Jody said, check the whole fuel system from pick-up to injectors. Do you have the pressure set properly? Typically it is 43psi with the vacuum line unhooked from the regulator or the engine off with the power on to the pump. This has to match what's in the controller as your pressure.

One test to do when you are hammering it. On the hand held controller, go to the live data and look at the injector duty cycle. If it goes over 90% while you are on it, you need more fuel pressure.

Just a few things to look at. Good luck.

Thanks for the tips and clues to look for I will be on it and under it this weekend thanks again

....and...... what did you find? Leaving us hanging here!!

I've had a few issues with the EZ-EFI systems but they have all been on individual throttle body manifolds. These direct runner manifolds have a very narrow MAP signal and you run through the same cells on normal driving as you do on moderate and hard accel so tuning these engines with a programmable system can be tricky. I don't think the EZ-EFI system is that smart and it will randomly tune in glitches. Sometimes they tune back out, sometimes you have to reset the program to get rid of them.

Had Alot Of Problems With Fast To Missing Parts They Sent The Ecm With No Software Installed In It Wrong Fuel Rails Only 4 Injectors In The Box

We've installed two systems using EZ-EFI, one on an Inglese individual runner setup on a ZZ4 crate motor, the other a TBI setup on the owner's ZZ502 crate motor. We never got either to run satisfactorily from our point of view, the Inglese barely acceptable, the ZZ502 virtually undriveable with a flat spot the size of the Grand Canyon. No amount of consultation with FAST seemed to help.

I think both of these could be considered more "edge cases", which may account for why other folks seem to be quite happy with EZ-EFI. Still, at this point I don't trust any of these systems that are "self tune only", with no laptop or other manual override programming available.