Thread: New block
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Old 05-29-2017, 05:59 PM   #265
Henry Floored
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Join Date: May 2010
Location: Florida
Posts: 547
Default Re: New block

Originally Posted by Bored&Stroked View Post
I think you have the right idea - as there are a zillion ways to build a flathead Ford. There are many guys that will want a 'new' and reliable engine that is close to stock specs (bore, stroke, etc) - there are others (like me), that would only buy a block like this if it can extend the performance capabilities beyond what is possible with a stock block. The primary area where I'd want the ability to 'finish' the block is in bore size and cam bearing size.

The other area where I think you'll need to really think about and then make some firm decisions is the whole valve train "package" that comes with the block --> you should include a much better port design (intake and exhaust) - such that everybody benefits from better flow. Some 'performance hounds' like me will take the "as cast" port designs and port/blend them even further - for larger cubic inches and higher performance. With this said, I would probably think about what initial valve sizes you include "out of the box" -- like 1.72" intake and 1.6" exhaust. I would not want to have to bore out and put valve seats into every block - that gets expensive for every builder. So - you might as well go with a larger hardened valve seat from the get-go.

With the above said, I'd still like the option of buying a block without any valve seats at all (would think at a cheaper price) - as if I'm building an OHV conversion (like an Ardun), it makes no sense to pay for them or for you to invest the machine work/parts/time . . . only to not use them.

Another peak performance idea just came to mind: Would be interesting to explore the potential to move the intake/exhaust bowl/guide locations maybe just a bit further apart. I've not done any measuring, but I will look into it (to see how much room is available), impact on heads/studs, impact on cam lobes (if it can be done), etc.. I would LOVE to have a larger intake valve (if the port could support the flow) - beyond 1.72" with a hard seat - and the only way for this to work is to move the valves a bit further apart. Anyway - just pondering the 'ultimate' design a bit further in my mind . . . will look at my CAD models when I get home next week. Something fun for me to look at . . . LOL!

B & S I'm intrigued with your idea of spreading the valve centerlines apart a little bit more. I think some careful thought should be given to not shrouding the intake valve more as a result of crowding the chamber wall.

Ford accomplished a similar thing some years ago when they were doing the GT40 and GT40P cylinder heads for the 5.0 engine.

Basically what Ford did was create a better exhaust port fitted with a slightly smaller exhaust valve which together outflowed the previous design.

Then that freed up some space for a larger more efficient intake valve and port.

Maybe a similar thing could be done with a Flatty.

I personally think but don't know for sure, that by moving the intake valve closer to the cylinder bore edge you could pick up a lot of flow.

It's all about relaxing that last nearly 180 degree turn the incoming charge has to make to fill the cylinder.
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