I was having problems getting my 350 to run right with the holley unit. It turns out it was the vacuum port on the TB for the MAP sensor. I just ended up putting the holley injectors onto the stock throttle body and everything works beautifully. My motor pulls to about 5200 in first and second. Hows that for a stock TB unit(oh yeah, ultimate TBI mods too.)

 

maybe you can help me, i also have a 350 put in my RS, cept its a 91,were the problems you happened to have associated with idling? im having a rought time getting mine to run right, feels like it has less power than my 305. anything you know that you think i should know, let me know : D, thnx.

 

Carbine, what's in the engine, what mods have you done? What is it doing that you say that it don't run right?

 

Its a 350 over 30, with a stock roller cam with a TBI. Ive just done this within the last month, and its the only thing ive done so far as far as modifying my car. Its not running right as in it lags after i step on the gas, it doesent go very fast, feels held back, and the idle is always jumping up and down from 5-10 rpm's making it difficult to drive out of the drive way as it all of a sudden just goes even though i have my gas on the pedal steadily. Im going to try replacing the Idle Air control Valve as a suggestion, and hopefully that will help at least with the idle for now.

 

If the set up is out of a 305 the IAC is freakin out, not knowing what to do with all that air and fuel, by the way if it off a 305, tell me your not useing the stock injectors, the stock injectors are 45#, you need at least 55# or you are not going to go anywhere. The IAC can be fixed with a custom chip and it would explain the fluctuation of the rpm, the lack of power could be the lack of gas and air, choking the engine.

 

Yes, im still using the stock injectors, which was a thot for me also, but most people are saying that ive talked to that the 305 and 350 computers are the same, therefore it should adjust to the amount of fuel needed, i even checked with autozone, same ECM's for both cars, my father said increasing the size of the injectors may not help, i would need to get an aftermarket chip burnt in order for the computer to even utilize more than the injectors i have in now, but were not positive about nothing.

 

Take that 305 ecm and punt it out the window. Get a stock LO5 (350 tbi) ecm and run that. The 305 computer will run you lean, as will the lower injectors. If you keep running lean you'll burn up your heads, it happened to my friend when he went from a 305 tpi to a 350 tpi.

 

The only thing that I ever changed on my engine from a 305 to a 350 was the injectors which were the holley ones. I think that their throttle linkage sucked and I had to rig so many of my cables especially the gas cable. I have a stock 7846 ECM with a jet stage 1 chip left over from my stock 305 days, and a stock 305 knock module and a stock ESC and evrything else that was on my 305. My engine runs great and has plenty of power.Air fuel ratio gauge says that my 350 is running right where it should be. Running 10° base timing and 10 psi fuel pressure with the holley regulator, which has a stiffer spring than stock to more precisely mantain pressure under WOT. I'm sure that I would benefit from running a more agressive chip but I would rather but a big block hood.

 

Holleys injectors are MOPAR products.

'nuff said