The Ford Barn

Al NJ · 05-12-2010, 06:39 PM

Is it okay to use domed piston Eddie Meyer heads on a 21 stud engine with flat pistons?
I realize there might be some compression loss, but could it be done?
Seems I read somewhere it could ???
Thanks

BrianCT · 05-12-2010, 09:24 PM

You can do it ,but performance will drop. They do look good.

Joe AZ · 05-12-2010, 09:27 PM

I think they'd look better on my 21 stud motor with domed pistons!!! LOL
Joe

Al NJ · 05-12-2010, 09:36 PM

They would go well with that dropped and drilled axle! LOL

Bruce Lancaster · 05-13-2010, 10:41 AM

They will clear...you will lose compression and also all the squish/turbulence in the chamber, possibly leading to knock and need to crank back on the distributor brake. This will be a significant hopdown for the engine.
By the way, I used to have original EM heads, and so i studied the repro pictures when the Oddo and Ceridono flathead books came out...I saw clear pictures of both flttop and dome piston versions in there!
Why not measure your bore carefully, then go visit Joblot with a micrometer? You might be able to find dome pistons compatible with existing bore and drop them in with the existing rings...I assume here your engine is in good shape.

Al NJ · 05-13-2010, 12:32 PM

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Thanks Bruce. I was thinking I might have to change the pistons, but I was thinking I would have to do new pistons, rings, and hone it.
Yours is an interesting idea. The engine appears to have a fresh rebuild.
I certainly don't want to lose any performance!
(Is WOG the opposite of GOW? lol)

Bruce Lancaster · 05-13-2010, 01:09 PM

On the Eddies...I would ask at the source...Orosco?? Whether they are available for flattop. I know from the picture I mentioned that they exist so, but was that an original or a recent one?? I used to have a pair of originals, but traded them a looong time ago and don't even remeber whether mine were made for flat or dome.
Piston change depends on finding a set that would be happy in existing holes. I think for a 221 there isn't a lot of choice of styles and manufacturers so you have a pretty good chance of finding ones requiring the same size hole for proper clearance as the ones you have. You will definitely need to measure and do some arithmetic before buying, of course.

Al NJ · 05-13-2010, 01:26 PM

I'm 99% sure my heads are original. They were on something once, but I doubt for very long.
I agree about the careful arithmetic.
I'd like to get them, and the intake, off my office shelves and on to something!

Bruce Lancaster · 05-13-2010, 02:02 PM

Mine were original for sure because I bought them 15 years before the repros came along. Now I have a set of Evans water pump heads (dome!), though, so I am still happy. I think they cost 10 or 20 times what I paid for those long gone Meyers...all this nostalgia business is a serious nuisance!

Lawrie · 05-13-2010, 04:48 PM

Bruce,could you not machine out the original alloy flat heads to fit the dome pistons. I have an old set ,I should measure the thickness.Lawrie

Brian · 05-14-2010, 01:49 AM

Al, In order to fit Meyer heads, you will also need to change out just about every headstud. The Meyers are thinner and need shorter studs. Hopefully, you can get them all out without breaking any. If I were you I'd build the engine with domed pistons, and new rings, give it a good valve job while you're there. You will definitely notice an increase in performance running those heads if everything else suits. It is not just a matter of 'chucking on your fancy finned heads'. I run Meyer heads in my 35. I love 'em! Brian

05-12-2010, 06:39 PM	#1
Al NJ Member Join Date: May 2010 Location: New Jersey, The Garden State Posts: 98	21 stud heads/domed/flat/etc. Is it okay to use domed piston Eddie Meyer heads on a 21 stud engine with flat pistons? I realize there might be some compression loss, but could it be done? Seems I read somewhere it could ??? Thanks

05-12-2010, 09:27 PM	#3
Joe AZ Senior Member Join Date: May 2010 Location: Prescott, WI Posts: 336	Re: 21 stud heads/domed/flat/etc. I think they'd look better on my 21 stud motor with domed pistons!!! LOL Joe Last edited by Joe AZ; 05-13-2010 at 08:42 AM.

05-12-2010, 09:36 PM	#4
Al NJ Member Join Date: May 2010 Location: New Jersey, The Garden State Posts: 98	Re: 21 stud heads/domed/flat/etc. They would go well with that dropped and drilled axle! LOL

05-13-2010, 10:41 AM	#5
Bruce Lancaster Member Emeritus Join Date: May 2010 Location: Madison, NJ Posts: 5,230	Re: 21 stud heads/domed/flat/etc. They will clear...you will lose compression and also all the squish/turbulence in the chamber, possibly leading to knock and need to crank back on the distributor brake. This will be a significant hopdown for the engine. By the way, I used to have original EM heads, and so i studied the repro pictures when the Oddo and Ceridono flathead books came out...I saw clear pictures of both flttop and dome piston versions in there! Why not measure your bore carefully, then go visit Joblot with a micrometer? You might be able to find dome pistons compatible with existing bore and drop them in with the existing rings...I assume here your engine is in good shape.

05-13-2010, 12:32 PM	#6
Al NJ Member Join Date: May 2010 Location: New Jersey, The Garden State Posts: 98	Re: 21 stud heads/domed/flat/etc. Sponsored Links (Register now to hide all advertisements) Thanks Bruce. I was thinking I might have to change the pistons, but I was thinking I would have to do new pistons, rings, and hone it. Yours is an interesting idea. The engine appears to have a fresh rebuild. I certainly don't want to lose any performance! (Is WOG the opposite of GOW? lol)

05-13-2010, 01:09 PM	#7
Bruce Lancaster Member Emeritus Join Date: May 2010 Location: Madison, NJ Posts: 5,230	Re: 21 stud heads/domed/flat/etc. On the Eddies...I would ask at the source...Orosco?? Whether they are available for flattop. I know from the picture I mentioned that they exist so, but was that an original or a recent one?? I used to have a pair of originals, but traded them a looong time ago and don't even remeber whether mine were made for flat or dome. Piston change depends on finding a set that would be happy in existing holes. I think for a 221 there isn't a lot of choice of styles and manufacturers so you have a pretty good chance of finding ones requiring the same size hole for proper clearance as the ones you have. You will definitely need to measure and do some arithmetic before buying, of course.

05-13-2010, 01:26 PM	#8
Al NJ Member Join Date: May 2010 Location: New Jersey, The Garden State Posts: 98	Re: 21 stud heads/domed/flat/etc. I'm 99% sure my heads are original. They were on something once, but I doubt for very long. I agree about the careful arithmetic. I'd like to get them, and the intake, off my office shelves and on to something!

05-13-2010, 02:02 PM	#9
Bruce Lancaster Member Emeritus Join Date: May 2010 Location: Madison, NJ Posts: 5,230	Re: 21 stud heads/domed/flat/etc. Mine were original for sure because I bought them 15 years before the repros came along. Now I have a set of Evans water pump heads (dome!), though, so I am still happy. I think they cost 10 or 20 times what I paid for those long gone Meyers...all this nostalgia business is a serious nuisance!

05-13-2010, 04:48 PM	#10
Lawrie Senior Member Join Date: May 2010 Location: Qld, Australia Posts: 4,215	Re: 21 stud heads/domed/flat/etc. Bruce,could you not machine out the original alloy flat heads to fit the dome pistons. I have an old set ,I should measure the thickness.Lawrie

05-14-2010, 01:49 AM	#11
Brian Senior Member Join Date: May 2010 Location: Masterton, New Zealand Posts: 3,834	Re: 21 stud heads/domed/flat/etc. Al, In order to fit Meyer heads, you will also need to change out just about every headstud. The Meyers are thinner and need shorter studs. Hopefully, you can get them all out without breaking any. If I were you I'd build the engine with domed pistons, and new rings, give it a good valve job while you're there. You will definitely notice an increase in performance running those heads if everything else suits. It is not just a matter of 'chucking on your fancy finned heads'. I run Meyer heads in my 35. I love 'em! Brian