ad356

had some questions on my 350. im running tbi fuel injection in my 89 camaro, the engine i swapped recently. it runs fairly well but doesnt seem like it produces all the power its capable of, i suspected it was running lean. i pulled one of the plugs and it had the white redisue that is a sign of a lean running engine. i hooked it up to my laptop(running WINALDL) with my ALDL cable and created a datalog file. i sent the log file to harisperformance(tbichips ) and he came back and confirmed a lean running engine. he suggested and sells a high volume high performance fuel pump and a 18 PSI regulator spring. i ordered these 2 items from him and im hopping that it will run with the proper mixture ratio when im done. what do you guys think??? does all of this make sense. he did say that the stock tbi fuel pump is very marginal and doesnt deliver enough fuel. stock 350 and 305 fuel pumps are the same
my engine:
350 punched out .040
edlebrock performer plus tbi camshaft
350 injectors that were included with the 350 engine (350 sized injectors, im guessing 55#, engine came out of a G20 van)
tbichips performance chip

ad356

doesnt anyone have any ideas why my car is running lean and if swapping a fuel pump and a regulator spring will help??

fiveoformula

The best way to find out would probably be a fuel pressure test. I was having lean problems myself a few months ago, checked fuel pressure with the tester inline (where the filter goes) and I was getting 9psi. I then took the fuel line off the throttle body and tested there (dead-head test) and I got 2-3psi.
Im assuming the only reason I had 9psi on the first test was because of the pressure regulator. Thats how I diagnoised my bad fuel pump, in which I replaced with a higher pressure TPI unit. Made me and my Wideband happy, and the car now runs great!