Injector question..

[Turbo6Smackdown]

Got an 04 cavalier. did nothing but throw some 42 pounders, turbocharger, and a Begi fuel pressure thingy seen here. Bell Engineering BEGI - The Original FMU - Rising Rate Regulator

i want to know, does this pcm need a changeover, for the injectors? Is the maf going to max out?

 

[DailyDrifter]

To answer your question YES. Your stock ecu has no clue what you did to the car and its going to try and compensate, and sometimes they can actually hurt performance to an extent. And that fuel psi regulator is just like a GN's for the most part, although some cars dont have a return line and have the regulator in the tank.

 

[TurboBob]

which engine in the Cav?

Is it a returnless fuel system?

Do you have a scantool of some sort?

How much boost?

Intercooler?

Does it actually run now?

Pics?

Bob

 

[Turbo6Smackdown]

Ah, Mr. Bailey. Just the man I was hoping would show up
I am posting for a close friend. Thought of you during our pcm conversation.
It's a 2.2 ecotec, with a return line to the tank. it is intercooled. about 7psi normally, and no scan tool, no nothin. It runs, and not bad actually. Pulls very good in third. It's a stock looking dark blue cavalier, that is lowered an inch, and that's about it. I can get pictures soon.

That's the thing though. He literally just tosssed the turbo, injectors and pressure reg, and went. He has zero idea of his a/f ratio, O2's, KR, maf flow, nothin... I'm slowly talkin him into a scan tool and WB O2.

He says, the fuel pressure regulator does it all for him. No need for any reflashes or nothing. It adjusts automatically. Here's his quote.


"Yeah my car has a MAP...and your right my ECM doesnt know about my 42s thats why I have a adj. FPR like you. Instead of 43 psi mine is set at 17!!! LOL When I hit wot and go boost, my map thinks im at Atmosphere and adds all the fuel it can (5v source on the map) but every 1 psi my FMU (fuel management unit. ie afpr) sees from the turbo it adds about 10-15 PSI of fuel...somewhere around.

So 17 psi at idle +10 psi from my Adj. regulator coming out of vac to 0. = 27psi.....now every psi x 10ish ..my car is running 9 psi so you do the math of how much PSI of fuel is being squirted or shall we say forced into my engine.

Stock fpr psi at idle is 55 psi on 19lbs injectors. so at wot stock my rail was seeing about 65 psi of fuel.

So my engine is getting alot of fuel!!!! LOLOL 100+ psi of fuel on 42 pounders, and i have my intank walbro 255 lph dishing out the fuel to keep up."

I was worried about him leaning out, or, riching out lol, and either blowing his creation up, or just riding it pig rich, and runnin like ****. I'm still baffled on how his car, with ZERO tuning or adjusting, runs pretty good..

 

[TurboBob]

it sounds like his combination is pretty well thought out. For being somewhat untuned it sounds like it probably runs pretty well.

A scantool would help him fine tune and work on any driveability issues. He needs to watch for knock, as his the stock pistons are not going to be heavy duty.

Tuning with fuel pressure is a proven technique, this is what we all did before the advent of all the new control gizmos.

Sounds like a cool ride. Two thumbs up from me!

Bob