I am in the middle of doing a facelift on my model B motor. I pulled the head bc of a gasket issue. While it’s off, I though maybe I can get a bit more out of the top end. I’d like to get a performance head close to 7:1 but I’m not having any luck w/ finding ones available at this current time... so I thought, well for $40.00 I can have a local guy deck my stock “C” casted head. My pistons are flush w/ my cylinder deck. Gasket is roughly .045” and flycut depth on head is around .065” so overall I have .110” cold of head space. I heard from a talented dude that .060”+- is a safe number overall. Question is: is it worth my time? What more will I gain to take off .050” off my head. I can cc it after. Of course it’ll be more that stock but maybe get it to 5:1..? Anyone been here before, or have some knowledge they’d like to share? OR..... Anyone have a good performance head they’d sell? Thanks, Matt Sent from my iPhone using The H.A.M.B. mobile app
Sounds like your on the right track for valve clearance.I would check a valve open at full lift for height just to make sure you have what you need.
I don't know how much you can shave a model B head. Sounds like you know someone who does. When I was a kid (high school age and early 20s) our common cut on a flathead V8 head was .010. That has little bearing on what you are doing other then the fact that we cut 'em for two reasons, square 'em up (which was an excuse) and the other was to gain compression. Compression gains is cheap HP.
This has been asked many times. Most responses are not to bother. Maybe a search might help but I remember one response with a cut away head to show why the answer was no. Also do you have Brierleys book on bangers? He can answer a lot of the questions you have been asking. His info is at the beginning of each banger meet.
I wouldn't bother. You don't get that much of an increase in compression and you risk cracks. See photo of an over milled Model A Police head. Probably not fatal but why risk it. If you need provision for a 3 bolt water pump there is a stock appearing, high compression, cast iron head being developed and it should be out soon. If you can use a Model A water pump a high compression Model A head would be a better choice. Charlie Stephens
I shaved/milled .060 off my Model C head and didn’t notice much difference either low end or top end. I recommend looking for a overhead to let the banger breath and a better cam . Bangers are cool but you can spend a lot of dough fast and with little improvement.. The Overhead isn’t cheap but wakes up the motor and best Bang for the buck ..
I just bought his book today. Looking forward on reading it. I’m not goin to go deeper till then. Thank you for the information!
this is true! The only thing is if I go that route I rather just put the cash toward a v-8 swap. Just would like this thing to keep up with normal traffic and have fun this upcoming season.
I figured the same. It’s probably not worth the time, I might just wait till a performance head comes my way.