Hi all. I've had my 89 Iroc for 11 years, and am now thinking about installing a 350. It's currently an automatic. I'm looking at the GM Performance 350HO base motor. My dilemma is trying to decide which injection to go with. Being that EFI packages have come and gone I want to see what technology is good for 2017. Looking at the Weiand Stealth Ram, F.I.R.S.T. TPI, or the Edelbrock Pro Flo (if it will work on my car). I'm not going to lie and say cost isn't an issue because it is. But I don't want to go with a system just because it's more affordable. If I do this swap I realize that I will have to do a custom prom tune (looking at a programmer from Moates). This is all in the planning stage right now, and just want to weigh all the options. This will NOT be a drag car. But I want to go for better than stock performance. Thanks for any input.

 

Welcome to Thirdgen.

What heads do you plan on running??? Pretty sure the 350HO comes with Vortec heads. It's changed over the years, but I think NOWadays....it's got the vortec 060 heads. Which are great! -but make TPI style intakes difficult. The two most popular options (SDPC/Eddy TPI base and Stealthram) no long make a vortec head option. There are plenty available on craigslist etc. etc., but just keep that in mind. FIRST "might" have a vortec option...I don't know.

***so I just checked ebay, and I see a few different places selling weind/Holley Stealthrams for Vortec heads. ....maybe they're making them again. If that's the case, that answers your question. No doubt I'd go that route for a 350.

You have a 305 TPI now??? -Officially, yes, you'll need a tune. Unofficially a stock 1989 L98/350 tune should run real well on that motor, assuming you give it the proper 22(24) pound injectors. Everyone has a different definition of what "runs well" means. I'd tune your set up, BUT....the stock 350 tune should "run well" LOL. I'll leave it at that.