Hey all! I never really post here ever! I dont know why, I just dont! I now come to ask a question. I have a 1991 Camaro RS, with a 1988 Pontiac Firebird Dashboard, gauges, and wiring, and a 1991 305 engine with roller camshaft, but 1987 heads, 1987 intake, 1987 intake plenum, with Edelbrock high flow intake runners, and a Holley 58mm billet aluminum throttle body. The throttle body coolant pipe is bypassed directly back to the radiator, no heater core. Also there is a mechanical fan on the front of this engine, the intake is shot out at an angle with a Mass Air Flow Sensor, to a stainless steel intake cone. This also has Headman shorty headers, 2.5 inch diameter Y pipe, to a 3" exhaust afterwards, with a side dump exhaust. Extremely loud, very throaty... Now that you know my odd setup, here is my concern.

I have a running rich issue. to understand what it is, let me tell you previous problems, and what has been done to fix or bypass them

NO CRANK:
Caused by ignition switch, aparently the lack of VATS in the new dash made the wiring not compatible, no crank, bypassed with a starter button

NO START:
No fuel pump, so routed the relay to the rear defroster switch. I click on the rear defroster, it turns on my fuel pump (Wow for perfect anti theft! no one will ever guess the defroster is the fuel pump!)

NO START #2:
Fuel injectors not firing, was lacking power to a SINGLE wire on the cut harness. forgot exactly what it was, but gave it power, everything works fine.

Hard start:
Major vacuum leak on intake runners, one was bent from the scrapheap (was an engine transplant, went from V6 auto to V8 standard). Bought new intake runners, and throttle body due to throttle body being damaged also. Starts up within about one or two cranks now, almost instantly

HUNTING FOR IDLE:
I fixed this with a coolant temperature sensor, fixed that, reset my timing by disconnecting the single wire near the blower motor. Timing is set, idles great!

CURRENT PROBLEM:
Runs rich, but idles fine. Sometimes backfires, and has a lope here and there. No vacuum leaks, already been through it with a fine tooth comb. MAF replaced after it was diagnosed bad, still eye burningly rich. Rev it, it revs up REALLY fast, perfect reving, though it seems to have a very small 1/4 of a second hesitation to the rev, timing maybe still off? Havent tested its power yet, need to get the hood on it and register it. No clue if the engine has a cam in it, block and cam assembly was given to me for free from a buddy, he had the 305 sitting around, diddnt tell me if it was stock or not, but by the way its idling, it MIGHT have a cam in it.

Possibly maybe I got clogged injectors? Should I send all the injectors out to get cleaned? or would it not be so easy to start with clogged injectors? I dont think its losing fuel pressure either, I can hear the prime bog down when I hit the fuel pump button. Though my cold start injector is NOT hooked up, couldnt get the connector on, the runners are so fat I cant get my fingers in there, and it still starts up so easy, so it might be injectors or maybe just IAT sensor? Let me know what you all think it could be! thanks for your help, and sorry if this question has been asked before!

 

wow, no offense but youve got a bastard of a camaro, anyways, for one, get that mechanical fan off and put an electric one on, the TPI computer controls that, second, what is your timing set at?

 

lol, yeah. I have a bastard of a camaro, parts from here, there, and everywhere. I liked the firebird's dash better anyway. The timing was set at 6 degrees before top dead center with that connector off. The mechanical fan was put on due to the electric fan not triggering at all, and I did not feel like messing with the wiring at the time. I like the mechanicals look now... I have a custom aluminum fan shroud. I may set up a push fan on the opposite side of the radiator as a secondary fan just in case of high traffic I can flip it on to prevent overheating :P.

What should Total Timing be on a 305 tuned port? I might just go ahead and set total timing instead of base timing!

 

your total timing should be set by the ECM if im not mistaken, but seeing as your engine is made of well, everything, what size injectors do you have? you SHOULD be running 19 lb injectors, also, is your ECM and prom for a 305 TPI or for a 350 TPI, if i remember correctly 6* BTDC is facory spec, though my 298 runs at 12* BTDC, so i may be wrong... also, to each their onw, but do know that mech fan is going to rob you of im sure much wanted HP

 

im running the stock injectors from the 1987 tuned port, that I pulled out of the junkyard. Never even changed them

 

we have 19# and 22lb bosch design lll injectors if you decide that you need another set.
PM
516-492-6504
info@southbayfuelinjectors.com

 

you MAY have pulled 22Lb injectors from a 350 on accident, that would make you run rich