Thread: Pat, Dave, Got a Head Question For Ya

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Erik and Pat are expert where I am a back yard engine builder at best, but what I can tell you that I do know is heads that are in the upper cc range of 113+ are typically open chambered heads. I have a set of 781 heads that I was gonna use and in my research in trying to learn about them as much as possible I dont one thing and that is the cc's on them can vary quiite a bit #1 and #2 that they are definately an open chamber head. Im sure words just got confused or someone is mistaken is all.

I think where the confusion has arisen is from my dad understanding that the engine builder said the KB160 pistons were made specifically for a close chamber head. I don't believe thats a good fact. Thats alot of dome to get into a small chamber isn't it? Course I'm a sb man so I haven't had the chance to check out too many bbc heads yet.I guess the 781 heads will work just fine. While I have you here whats the scoop on the 049 heads? Thanks guys.

Originally Posted by jimmyjeep

the engine builder said the KB160 pistons were made specifically for a close chamber head. I don't believe thats a good fact. Thats alot of dome to get into a small chamber isn't it? While I have you here whats the scoop on the 049 heads? Thanks guys.

I dont know anything about the pistons your dad is using but for example my 2349 TRW forged pistons have a decent sized dome on them and they are a "Closed Chamber piston" that can work with open chambered heads like the 781s and 049s....You actually need that dome a little I beleive to get the compression up on the opne chambered heads; so I wouldnt be surprized that the KB pistons your Dad has are closed chamber. 049 heads to my best knowledge are very similar to 781 heads except thier chambers are 121-122 cc versus the 781s at 118-119cc. Besides that they are very similar from what I have read; either of those heads in oval port configuration should work for your Dads engine. Im sure the experts on here can give you more/better info than I can.