Hello everyone. I was wondering if anyone knew of specific casting numbers for the cylinder heads with the swirl port bump in the intake tract? After some researching on past threads, 187 and 193 seem to have that design. I was also wondering if these heads were restricted to TBI cars and/or trucks.

I have 081 castings on my LB9 and am considering some options as far as porting or replacing them. Someone had warned me about the bump in the intake tract, but it would seems that i am safe from this, although i haven't had the lower manifold off to check for sure.

Thanks,
TurboSteve

 

If you have 081 castings you are in good shape. A good port and polish job and they will flow nice. Sitting Bull has a good article in his sig that esplains how he did his.

 

You will only find the 187's on 305 TBI's and 193's on 350 TBI's. They didn't make their way to any high performance engines.

 

While we're on the topic of these two different heads (193's and 081's), does anyone know flow numbers for both, or which would flow better (my 081's are slightly ported and polished, with new valve job). If the 305 081's will flow more I'm definitely going to swap them in for the 193's on this Caprice LO5.

All opinions appreciated, Thanks.
-Ben

 

You can either do a search of "193 heads" in the forums for more info and/or look here...
https://www.thirdgen.org/techbb2/sho...hreadid=177465

and here...

https://www.thirdgen.org/techbb2/sho...hreadid=192114

Probably would want to look at Dyno Don's numbers. As well as a few other people who actually have experience with them, have some useful information also.

 

Ya actually I've read both those posts, and done some research on 193's, didn't find a whole lot. I just wondered if anyone had some real side by side comparisons (flow numbers) or by experience. I would guess the 081's would still flow better even with the .1" smaller diameter intake valves (with the porting). Exhaust valves are the same I think. So ya, just wanted to know if anyone had some usable experience in which I could compare the two.