Is there any difference between TPI and TBI heads?

 

Tons.

The 416 casting 85-86 TPI 305, are quite a good head. The 87-92 081 casting are the same runners and slightly improved combustion chambers, but overall the same head.

The 88-95 187 casting TBI head, is a torque producing head that has cast-in swirls and valve shrouds to build low speed torque. Very bad for high RPM's. They typically can only feed a 305 to max 5000rpm and a 350 to about 4500rpm.

 

The reason I'm asking is that I found a great deal on a set of heads off of an 85 TBI Z28. I have an 86 TPI iroc that I want to put them on. Will they work allright?

 

Well, the first year for TBI was '87, so I'm guessing something's wrong.
If you can get us a casting number (stamped somewhere on the heads) we will be able to give you a better response.
As for the TBI heads, I wouldn't recommend them, as they limit airflow for torque, as iroc22 said. These heads would be a step-backwards if you were to take off your TPI heads.

 

I assumed it was TBI but I am not that knowledgible on all of the thirdgens. The only thing that I really know is that the 86 was pretty weak as far as horsepower goes.Unfortunately thats the one I have!) I know for sure that this 85 is not a TPI. So if it is just a plain carberated one will these heads work? I found them at a pick and pull junk yard and I only took a quick look at them. I'd like to have some insight before I pull them off.

 

They will be the 416 heads and they are exactly the same head on the TPI car.

They're a great head to port and if you can get them cheap, then that's great.

 

Porting is my plan. I'm picking them up for $60 for both...I think that is a pretty good deal. Thank you for the help.

 

Definitely a good deal for $60. Grab 'em.