robster66

iTrader: (1)

I am looking for a IROC camaro and I found one. The guy said he thinks it was replaced from a 305 TPI to a 350 carb. Are all IROCS the same as for suspension, transmission, etc, weather it's a 350 or 305. I was originally looking for a 5.7 350 TPI but how would a 350 carbed compare to this?

robster66

iTrader: (1)

bump

1bad86z28

As far as I'm concerned, there is nothing better than TPI. If you want to switch it I have an extra TPI setup, I upgraded my whole sytem and kept all the stock stuff.

five7kid

iTrader: (14)

Welcome aboard thirdgen.org.

First, I hope you realize no 3rd gen 350 came with carb from the factory. I think you do, but need to emphasize that. So, any VIN 8 car that has a carb has been modified. That means that any comparison we attempt will have to be done with a complete understanding of how the modification was accomplished. Without that information, everything will be speculative and generalized.

So, in general: An engine that started out as TPI and now has carb with nothing else done will generally have more high-RPM power potential, with a slight loss in low-RPM torque. But, with nothing else done, the power won't be significantly higher, and the torque loss will be noticeable. Fuel economy will generally be reduced without a lot of knowledgeable, high-dollar-equipment-available tweaking to what is generally available with carbs.

As far as transmissions, to the best of my knowledge the only differences would be year-to-year variations - 1987 TH700's, the first year the L98 was available in 3rd gens, were not quite as good as say 1992 TH700's. But, not significantly different from a performance standpoint. There were suspension options that could vary from IROC to IROC, but not because of 305 vs 350.

That isn't a lot of help, but we don't have a lot of information to go on. To provide a better answer, find out exactly what carb, intake manifold and distributor was put on the car, what they did to provide torque converter lock-up function, and what else, such as exhaust, was done to the car.

TexasSilhouette

iTrader: (4)

Most EFI to Carb swaps I've seen were done by folks that were confused by EFI and wanted to go back to old school so they did not feel their car was smarter than they were. These were generally (but not exclusively) hack jobs. Look for crimp connectors on wires, zip ties used to hold things together, electrical tape anywhere especially if it's not on electrical wires, and hose clamps used to hold pieces together.

The few clean swaps I've seen were performed on cars that were intended for more track use than street use and they served that purpose very well. They were not worried about fuel economy, cold starts, or passing a state motor vehicle inspection either.

Without knowing the competence of the person that did the swap I don't think anybody can give you 100% reliable information but if you intend this for a daily driver my opinion would be to avoid it.

TPI will have better drivability, reliability, economy, tunability (up to it's RPM limit with stock intake), lower emissions

Carb will not have as low an RPM limit as a stock TPI.

all aspects of fuel and timing on TPI can be adjusted from the drivers seat with inexpensive equipment. Carbs require an open hood for any and all adjustments.

Good luck

robster66

iTrader: (1)

I appreciate the responses I am buying this car soon. Im suppose to be going to look at it sometime this or next week. It had a stock 305 TPI and now is 350 carbed.

five7kid

iTrader: (14)

My apologies, I missed the part about it being 305 originally.

That makes everything pretty open-ended. Find out as much as humanly possible about what is in there, because there are plenty of carb 350's that made less power than the original 305 TPI.