I have a 91 TBI long block laying around. Are the heads the same as the 89 305 TPI i have now? I think they are, i just want to make sure.

 

Most of time 305 TBI heads are swirl type heads. The TPI are NOT.

What is the casting number and I will tell you?

 

305 TPI heads are 081s
I forget the TBI #, but if you look in the intake port you should see the swirl port obstruction.

 

Well, this isn't what i wanted to hear. Now i remember this topic before. I will have to check the casting numbers... its too cold outside for me to get my warm butt off this chair. I will check tomorrow.

 

TBI's are 187's.

------------------
Chronologically challenged. But still kicking!
'92 CAMARO RS
305 TBI 5/spd (now TPI)
B4C Alt.
Cam change:TRW 198/210 ,450/.460 114 LSA
Stock TBI manifolds
'85 IROC Ex.
14.94-92.00 mph
SPDC base and "350" Vortec coming soon!
'69 camaro-BB/Lenco,1050 dominators, /Pump Gas/no drugs 8.97-150+/3200lbs.
SoCal Thirdgen F-Bodies

 

OK, the heads are 14102187 as stated in the previous post they are TBI. So, do all TBI heads have the swirl port? Is it that some TBI engines got the TPI heads and that is why some people can use the TBI heads on a TPI. Also, would it be a downgrade to put these 187 heads on my TPI?

 

AFAIK all 187 castings are swirl port. Thats kind of the point of a casting number, it tells you the mold that made your head...
And yes, putting swirl ports on in place of 081s is a big step down. If you look down the intake port you should see a raised vain (sp?) that 'induces swirl' as the mixture enters the cylinder. This promotes efficient low end atomization, but all that induced swirl takes away from the kinetic energy of the mixture moving down the intake, thus they aren't efficient at actually moving air.

------------------
Ed Maher - Moderator @ The TPI & Carb Boards
92 Z28 Convertible - Quasar blue / Tan top
305 TPI A4 2.73 - 14.7 @ 93.6
Stock except ported plenum and dual cats
-=ICON Motorsports=-

- Definitely prototypes, high powered mutants of some kind. Too weird to live, too cool to die

 

Would it be possible to grind away the swirl port? If so is that the only difference between them and the TPI heads?

 

I believe the answer to that question would be no, don't waste your time.

------------------
Chronologically challenged. But still kicking!
'92 CAMARO RS
305 TBI 5/spd (now TPI)
B4C Alt.
Cam change:TRW 198/210 ,450/.460 114 LSA
Stock TBI manifolds
'85 IROC Ex.
14.94-92.00 mph
SPDC base and "350" Vortec coming soon!
'69 camaro-BB/Lenco,1050 dominators, /Pump Gas/no drugs 8.97-150+/3200lbs.
SoCal Thirdgen F-Bodies