Roof 16 head and domed pistons

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Alex Dragone
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Roof 16 head and domed pistons

Post by Alex Dragone » Mon Apr 22, 2019 3:50 pm

I am currently building an engine and have a Roof 16 valve head model BB and I am wondering if I can use the high compression domed pistons sold by parts vendors. I will be using a scat crankshaft as well. Any thoughts are appreciated. Thanks


Scott_Conger
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Re: Roof 16 head and domed pistons

Post by Scott_Conger » Mon Apr 22, 2019 7:16 pm

What is the thinking of adding high compression pistons to an engine fitted with a high compression head? I'm not overly familiar with ROOF setups but believe that most certainly they were higher compression to work with the overhead valves...
Scott Conger

Full Flow Float Valves - deliver fuel like Henry intended!


tman1913
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Re: Roof 16 head and domed pistons

Post by tman1913 » Mon Apr 22, 2019 7:52 pm

High compression piston will help in boosting the compression ratio. Standard T Model pistons would be lucky to give you any boost in C/R.
Scott the combustion chamber in Roof's overheads usually have more CC's than a stock Ford head.

Measure the volume of the combustion chambers in C/C's and let us know what piston you are planning to use. You stated that you are going to use a Scat crank, which one, Standard T or a Stroker.


Erik Barrett
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Re: Roof 16 head and domed pistons

Post by Erik Barrett » Mon Apr 22, 2019 10:23 pm

The overheads made in the T days were very low compression, not much more than a stock T, because the gas available then did not work well with high compression. The idea was flow with these heads. With modern fuel, you can use high domed pistons to improve performance.


Scott_Conger
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Re: Roof 16 head and domed pistons

Post by Scott_Conger » Mon Apr 22, 2019 10:28 pm

Mike/Eric

thank you for the lesson!
Scott Conger

Full Flow Float Valves - deliver fuel like Henry intended!


Kevin Pharis
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Re: Roof 16 head and domed pistons

Post by Kevin Pharis » Tue Apr 23, 2019 1:27 am

I think the real question here is... how tall above the deck do the H/C pistons stick up above the deck? Most overheads have C/C depths between .875” and 1.125” depending on make and model.

Ross pistons has a O/H piston on file, you spec the height to get the C/R you want


Erik Barrett
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Re: Roof 16 head and domed pistons

Post by Erik Barrett » Tue Apr 23, 2019 1:59 am

Ross makes beautiful pistons, the nicest I have seen. They made the custom set we use in the Wild Cherry. They can make whatever you want if you need something special but have programs to make anything they have already done.


got10carz
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Re: Roof 16 head and domed pistons

Post by got10carz » Tue Apr 23, 2019 8:56 am

I have running BB.The stock Laurel pistons are flat top and come out of block 15/32".


got10carz
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Re: Roof 16 head and domed pistons

Post by got10carz » Tue Apr 23, 2019 9:00 am

Also I modified Ford Escort exhaust valves if you need valves.


Les Schubert
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Re: Roof 16 head and domed pistons

Post by Les Schubert » Tue Apr 23, 2019 10:44 am

I found a Mercedes Benz valve that fit about perfectly!!


Les Schubert
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Re: Roof 16 head and domed pistons

Post by Les Schubert » Tue Apr 23, 2019 4:26 pm

CDD27A05-9972-4C46-BB59-D1944E2B8C17.jpeg
I used these valves

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