I do not know if this has been asked before, but I searched and didn't find anything. Just conversion questions.

Anyway, what would you pick if you had the choice between a 305 TPI, or a 4bbl 305? I'm looking at '82-'87 Z/28's and was wondering which would be better for maintenance, MPG, repairing, modding, etc. I've heard things like that the carb's real old tech, (which it is) that TPI's have discontinued parts and are hard to open up.

Thanks.

EDIT: I also am very wary of the 4bbl H.O. because GM discontinued it because of fuel (or oil, can't remember) boiling problems and that worries me a good bit.

 

i originally had a carb'd lg4 ran like a raped ape, not bogging no fuel boiling... tired of smelling like raw fuel though when i got out of the car went TPI and wish i did it a long time ago...

 

TPI is great .. stock. If you're not looking to do any serious performance mods, it'll be just fine. Once you start modding them, though, you'll never get it to run right. I've been on a 2 year mission to get my tune to line up with my built bottom end. If you're gonna mod it, definitely go carb (or LT1) and don't look back.

 

funny, mines fully mod'd and supercharged, runs like a champ no issues.

 

What would be considered serious performance mods? I want to restore my third gen and keep it mostly stock. The only "mods" I want to do are maybe new filters, spark plugs, and maybe a new distributor. Only thing other than that would be a set of Flowmasters or Glasspacks.

 

Skip the glasspacks, they'll make it sound like an old farm truck. Serious mods are heads/cam/stroker type things. If you just do basic bolt-ons and exhaust, that's pretty much considered "Stock", at least it is to me.

If that's the case, definitely go for a TPI car. Why not the 88+ thirdgens? 86 cars got the awful tiny terrible factory cam. The 85s were okay, but the 87-92 cars got factory roller cams, which are a big deal for long term reliability and great for future mods if you ever decide to do that. Plus the 88+ years had 350's available. (although dont trust anyone who claims it has a 350, they all have 350's at this point... from corvettes. )

We moved on beyond carbs in the 80s for good reasons. The only reason any of us run carbs today is because with heavy mods, the old computer injection systems get grouchy, and the tuned port injection setup just doesn't respond to those mods very well by nature to begin with. If you're keeping it mostly stock, there is really NO downside to a TPI car.

 

I envy you, my friend. You are the exception to the rule.

 

My extreme TPI runs beautifully and has since I built it 13 years ago. In fact with each little touch since the original build, it just gets better. Putting together a good combination of parts and knowing how to make it work. That's what it takes. You would have a hard time making this much power from a carb intake setup without giving up alot of drivability. I know, I see peoples' cars all the time that have tried.