Technical Flathead Porting: Soup to Nuts . . . Pictures, Details and Opinions

Got my target to the tune of a 13.398.

 

this is a great thread ......

 

I agree. Great thread and glad to have something to bring it btt.

CNC carving combustion chambers. "barrel shape" as mentioned earlier in this thread. Did a bunch of flow bench testing on chamber shape.



Flat32

 

Thanks for sending me eMails of all your progress/results from racing - you've made unbelievable strides in your designs. Do you happen to have some completed pictures of your chamber designs - to show the masses? It is not for me to share, so I thought I'd just ask! Also, maybe what valve sizes and cam patterns?

Anybody who is really interested in what folks can do with a LOT of design work, testing, casting, dyno, racing, etc -- just checkout what Ray has done on the links above, extraordinary work!

Take care . . .
B&S

 

You can still buy big port intake gaskets from Baxter Ford Parts in Kansas either for $12 or $14;just bought some about a month ago.I would be willing to "loan" out my homemade 2/2 tunnel ram for someone to try it to see if it "works"; looks good on paper,but needs to be tested! Give me a call if interested flatheadjohn47 Texas 979-595-7324 cell.

 

Bump please, heavy research going on here.

 

Been a while since this was near the top. Bump so I can find it again soon. Gonna have my buddy write a program to trim the tops of guides in his CNC lathe. Also hope to line a pile of used guides since trustworthy new ones aren’t common.

 

Good thread, cant believe its been over 10 years since I last posted.

 

Hey you bunch of Flathead nuts . . . good to see the revival of the half-dead! The good news is that I just got home from running around with my 32 Cab (very heavily ported of course) with my friend Andy who I helped build his 302+ inch flathead (heavily ported of course) and these two cars/engines are so much damn fun. This is like being a 7th Grade kid and seeing your first pair of . . . yeah, those! LOL

 

Thank you for posting such a wonderful, informative thread.
Solid gold that never gets old.

 

I was poking around on the Manley website last night and they have a myriad of 1.5 valves with different stem diameters. Any tried and true part numbers that would work with a SBC sized guide liner? Don’t want to have my machinist buddy buy new reams and tools just for me. What kind of clearances are needed on the valve stems for intake and exhaust?

 

Manley 12342-8 Manley Severe Duty Series Stainless Steel Valves | Summit Racing
SBC Manley Severe Duty Intake Valves 1.720, 4.911 length, .3415 stem diameter (which helps with high lift flathead cams - which have smaller base circles, so a longer valve takes up some of the "slack". Since these are intake valves (not 1.6" exhausts), they have a nicer profile in the heads and are not as thick as the 1.6" exhaust valves that everybody runs.

I put 1.750" hard seats in the block - SBI Part # SB1750. In order to do this you have to have the tools/shop remove the old seats and bore out the valve seat pockets and use about a .005 or so press fit.

There are plenty of racers that just remove the intake seat all together and grind the seat right in the block. This works just fine!