Inliners International Forums General Discussion Engines porting a 261

After getting a price ($700.00) to port the head of my 261 I'm wondering if the bang will be worth the bucks. Here's what I've got - 261 bored 40 over, "bulldog" cam from Tom Langdon, solid lifters,Offy 2x1 intake (haven't picked out carbs yet),Fenton headers mated to a T-5 with Ford 3.55 rear end. How much difference will I see/feel with a ported head. This is a street driver Chevy '53 sedan 210.

For street driving I don't think I'd spend $700. Since you are running primarily bolt on speed equip that will give a reasonable boost with the stock ports I doubt you would feel the difference even if you covered the seats with sandpaper.
If the port work flowed better than the Offy intake and the exhaust system then they would be the bottleneck. Maybe a nice port match on the head and manifolds is the best compromise for what you are doing. You won't feel that either on the street but it makes good bench racing when showing off the car.

The attached link (if I did it correctly) shows the results of a 1955 porting job for a 261. is 10 to 15% more HP worth $700?

Hoyt
II #922


261 article in may 1955 HRM

Droped off the head today at the machine shop. They are going to port the combustion chamber and if I remember right "blend the bowls" Like Mike G says- probably just something to talk about and not much else. I had already smoothed the combustion chamber and the intakes, but didn't have the tools or the nerve to finish them.

Hopefully the machine shop has a good deal of experience porting old Chevy 6's.Even a flow bench is no guarantee the modified head will work well,especially on the street.
The 235 type head is a horrible piece from a performance standpoint,and not very fuel efficient.

Has anyone ever published flow bench test results for a 235 head, with or without a porting job? It would be curious to see how it compares to a later model head (e.g., a 250 or 292), or to a Wayne 12-port head. What is the correct procedure for conducting a flow bench test on a head with siamesed ports? Just open one valve at a time?

Hoyt, II# 922