I have a 52 F1 with a 255 flathead that has been totaly rebuilt. My problem is I put a high lift cam in it and have aluminum finned heads and do not have enough valve clearance. I have machined the valve cavity in the heads by hand with my die grinder and various grits of sanding discs and it is getting close. My question is, is it possible to increase this clearance by using a shim gasket along with the steel head gasket or just use two head gaskets to increase this clearance. I am getting tired of machining the heads and I am also going to be in trouble with spark plug clearance.

Any experience out there with this problem

Thanks

WGC

 

The guys at this link are the best for this kind of info.

http://groups.msn.com/FordFlathead19...3/general.msnw

 

MTFlat is right, the guys there will set you on the path. But I have to ask, why not just use a regular composition head gasket? Would everything clear if you did?

 

Thanks for the reply, I will check these guys out. I am using a steel head gasket and it is the basicly the same thickness as a reqular head gasket so it wouldn't help. I did some research on what gasket to use with aluminum heads and came up with the steel one, some people recomend copper but it will cause electrolisis (not spelled right but) between the copper and auminum. The problem is the high lift cam.

wgc

 

1. Are the valves hitting the head now?
2. If not, have you clayed the heads to see what clearence you're getting between the valves and head and also between the pistons and the head?

 

I am placing the heads on the block without a gasket and turning the engine by hand and I can feel the lift of the head when the valve rises to its max, I then take it off and machine a little more off that area, I am going to do this untill there is no valve interference and then with the gasket installed I know I will have enough clearance. My other worry with doing this is I can see there will be an issue with spark plug clearance as well, thats why I thought I may be able to install a second head gasket to fix this. I don't see why it wouldn't work other than it affects my compression, but it still may be OK.

Thanks

wgc

 

Out of curiosity, what cam did you choose that's causing the problem? And what brand heads?

I can only assume you've already set valve lash. Are you using stock valves or Chev ss valves that need to ground to fit?

Using double head gaskets may be a solution, but then why bother with aftermarket heads in the first place? Not trying to rain on your parade, just thinking thru the problem.....

 

Thnaks for the help.

The cam is a 3/4 grind, the valves are stock with adjustable lifters and already installed. The motor was rebuilt by a local shop that specializes in engine rebuilds and does alot of flathead work. I probably made a mistake with the cam but I will have to live with it. The heads I have a aluminum finned manufactured back in the 50's under the name of Schrager Automotive Engineering, can't find any info on them, they were in good shape so I bought them. I think even the stock cast head would have to be machined to work in this case but I should put one on and try it.

I can't seem to put any pictures in the message but I have some in my gallery.

Thanks
wgc

 

Confirm cam and heads are correct for your block, something is definately not kosher. Do you have enough thickness in material you are grinding on to be ok to run after metal is removed? After market auto parts stores such as NAPA can select a sparkplug with a shallow depth into heads. Have a great day, chuck

 

It's not uncommon to have to clearance the heads on a flatty with a hot cam, this one must have a lot of lift. With an uncommon head like these, the issue is how much meat is left in the valve pocket after you machine them. With Edelbrocks or Offies, it's well-known.

 

I don't think I have taken enough material out of the head to cause a problem, they are pretty solid looking heads, the original condition of the valve cavity was an uneven surface (probably to increase compression) around .020" - .030" over about half of the valve cavity and I flattened out this area, I have probably taken off close to another .010" over the complete area. I have found also that my piston dome area is too small and have opened it up slightly as my block is bored .060" and I am using a 4" crank. After last nights remove the head, adjust, put the head back on routine I am very close to being clear without a gasket, when I put my gasket on it will give me enough clearance. It is just time consuming as I am not removing very much material at one time. I have been unable to find any information on Schrager Automotive Engineering anywhere and if anyone has heard of them let me know. There seems to be differences of opinions of what head gasket to use with Aluminum heads, I decided on steel as the steel - aluminum contact should not create as much electrolisis as with copper but copper seems to be the choice of many.

Thanks
wgc

 

The only information I could find about Schrager Automotive Engineering was Skokie, Ill/gasket production/ Fel-Pro brand by Federal-Mogul sold by Summit Racing Equip. Hope this helps. Have a great day,chuck

 

I would imagine those heads have been machined a few times over their life which would have closed up your clearance in the valve area. New, they may not have needed much work at all for clearance. Do you have any history of your set to know how much as been machined or planed off to make them square again? I'd think they'd be heavy enough that you can open them up like you are doing and not have any problems, but the more they've been surfaced the more you'd have to remove.

 

I believe that the heads had not been machined at all, the surface of the head had an original looking surface and not a ground surface, I measured the piston dome area on my stock head and it was the same. There is plenty of material in the heads so I think I am ok with a little bit of fitting work. It will be interesting to see how it runs and also what the compression ration is, I have a good idea of how to measure this but if anyone has any good sugestions I am eager to learn.

Thanks
wgc

 

Sorry I can't help you with the clearance problem, but I do have a question. I looked at your pics in your gallery and want to know were you got the paint for the engine block? The engine looks great!