Hi, I have a question about cylinder heads. I am abuilding a new 355 for my gta and i found a set of heads with the casting # 10110810. They are listed as 91-up GEN. 1 heads with a 65cc chamber and 1.94/1.50 valves. I am planning on picking these up and doing some port work, bowl port and grind for 2.02/1.60 valves. I was wondering if anyone had come across a set of these heads or have used them and could tell me anything about them. Thank you for any response.

 

I don't know the casting #; but there are oly a very few kinds of heads that they could possibly be, and the odds are better than 90% that they're TBI swirlies.

Before you lay down you money, look in the bowl in the intake port right behind the valve for the ramp, and if you see it, walk.

 

I am pretty sure they are off of a tbi, but it is a 350 GM crate motor that shares the same block casting $ as the ZZ4. Even with enough port work and bigger valves, do you think they are better than th stock L98's

 

www.mortec.com/castnum.htm has the 810 casting as:

10110810...91-up...350..........Gen. 1, 65cc chambers

and that looks like you already used Mortec's web site for the same info.

The 90% chance it's a TBI head comment is accurate, and probably a light truck or van application... and that means swirl ramp port on the intake ports. Those heads, in stock form, flow about the same as L98 iron heads (083 casting), so they aren't better nor are they worse in stock unported form.

If you port them they'll flow just about as well as the 083 heads on the intake side, and they'll flow better on the exhaust side. I wouldn't spend any real money on them (there are many better but much more expensive choices) --- on the other hand if you already own them or can get them cheap, you can do very well with them with DIY porting. The evidence on TGO suggests that the stock-sized valves are adequate for decent flow numbers, so if you opt for the bigger valves you MUST unshroud the periphery on them or you will get no flow gain for the machine work (cost) in cutting the larger valve seats.

 

Thanks for the reply. I do own these heads. Thay were give to me. So there is no money there. I can port these myself, also no money. The only cost is parts and grinding for larger valves and my machine shops me a good deal because i give him so much business so i think i will try them. the only reason is because i am not pulling my motor til my new one is done.