Got a FD with a few mods done to it. It was formerly a show car and has a G-Force ecu as one of the mods. There was a dyno done to show the hp, but I think it was tuned to show some extreme hp, cause on the dyno graph it also showed an A/F ratio. It started around 14 at 3.5k rpm, and just went down to AT or BELOW 10. That, I think, is the reason the previous owner and myself have lost an engine to this car.

My question is, if I get a rebuild and break the car in, can I get the car dynotuned on this ECU, and can't I program it? Does it have set parameters that can't be altered? Otherwise I'm just going to probably go el-cheapo tuner wise and get an s-afc2 or something, tune it to that, then sell the car.

 

The G-Force is a rechipped stock ECU. You can't simply program it like a programmable ECU.

What mods are on the car?

 

G-force ECU, Greddy - intercooler, pullies, cat-back, throttle body elbow, midpipe, atr downpipe, pettit cold air intake. Those are all the performance mods.

 

It's most likely that midpipe the problem child. Most of the rechipped ECU's don't recommend using a midpipe with them. Pettit is the only one I know that used to support that for their chip.

Doesn't mean it can't be done, it just the manufacturers of the other ECU's didn't suggest doing it.

Throw a hi-flo cat in it's place and you'll be fine.

 

How would that make a difference, and how would I find out specifically what G-force recommends?

 

The midpipe is going to flow more than a hi-flo cat. If the G-Force ECU isn't providing enough fuel to support the CFM being pushed through a midpipe, then you have a lean condition which can equal detonation. Using a hi-flo can add some restriction, thus keeping you safer.

You can't, the company is gone.

 

Ok well that's worth looking into. Sounds like there's little or no room for dynotuning without something to be tuned, since the ECU can't take outside parameters.

This is just because I don't understand, but how could the absence of a cat cause lean conditions in the combustion chamber? My only guess would be something to do with backpressure...but I thought turbos didn't like that. I mean, once the exhaust leaves through the exhaust port in the rotor housing, the engine considers it a done deal, right? Unless it's something to do with excess heat from the midpipe somehow effecting the engine, heat the cat would normally help absorb? I'm confused =T

 

Reducing backpressure allows more air to flow through the entire system (which also typically means higher and uncontrollable boost). More air coming in, means higher A/F ratios.