Will these heads fit on my 302?

[32 Chevy]

I think I want to bid on some Ford heads that have 1.9 intakes and 1.5 exhaust valves, but without opening my motor I don't recall if the pistons in my stock '78 have valve reliefs cut in the piston tops. I know the existing stock heads have valves approximately 1.78 intake and 1.46 exhaust so those big valves should really ler 'er breathe.

Anyone out there know if these large valve heads are interchangeable with any 302 or are there specific pistons required?

Thanks!

Dave R

[Pope Downunder]

I think I want to bid on some Ford heads that have 1.9 intakes and 1.5 exhaust valves, but without opening my motor I don't recall if the pistons in my stock '78 have valve reliefs cut in the piston tops. I know the existing stock heads have valves approximately 1.78 intake and 1.46 exhaust so those big valves should really ler 'er breathe.

Anyone out there know if these large valve heads are interchangeable with any 302 or are there specific pistons required?

Thanks!

Dave R

Dunno; sorry!
Logic however suggests to me that it would depend a lot on the cam.  As the exhaust valves are only .020" larger in radius, it is likely they would clear.

If you want a better answer, you could try here;
http://www.corral.net/forums/forumdisplay.php?s=c33c3e84f48099dd1edc9feb931804e7&f=290

Also, you should check out the compression ratio, particularly the DCR
http://bcma.stangnet.com/downloads.htm

[Pep]

Its not the valve size, its the cam lift that you need to be wary of. It was common over here to run larger valves in Windsors with flat top pistons. So you won't have any dramas with those heads. You might want to open up the ports before you plonk them on. Match port the manifolds as well. Windsors need to breath .The heads are the weakest link.

[Dirk35]

I have the 289 heads with Chevy 350 valves in my Ford 302.

Not sure if that helps. I have a pretty wild cam in it too.

If you switch to Roller Rockers, be prepared to come up with some different (not stock) valve covers or the spacers the go in between them. You can get the spacers from Summit for $89 and the cool looking older "mooneyes looking" generic covers off of e-bay for $60. Go Figure! Im told that the older Eldebrock "straight script" finned covers will actually clear the roller rockers, but am not of any actual experience of it. They sure do look good though!

[32 Chevy]

I have the 289 heads with Chevy 350 valves in my Ford 302.

Not sure if that helps. I have a pretty wild cam in it too.

If you switch to Roller Rockers, be prepared to come up with some different (not stock) valve covers or the spacers the go in between them. You can get the spacers from Summit for $89 and the cool looking older "mooneyes looking" generic covers off of e-bay for $60. Go Figure! Im told that the older Eldebrock "straight script" finned covers will actually clear the roller rockers, but am not of any actual experience of it. They sure do look good though!

Oops, sorry about the double post....

Anyway, could you tell me more about the .202 chevy valves in the 302 heads? How much modification is needed for the valve seats? How about the length of the vlave stems, etc.? This sounds interesting!
Is there a point of diminishing returns for valve size in a regularly street driven motor? If the valve gets too big, then do you lose flow velocity?

Thanks!

Dave

[Dirk35]

The heads were given to me free by a guy who switched to the Eledbrock Aluminum ones, and were already modified.

I can tell you that the mashinist at Dunsworth Machine in Enid, OK stated that is very common and they build a lot of 302's for roundy-round racers and local drag racing. He took one look at my heads when I brought them in, and said......." I see you already put the chevy valves in. Good deal, thatll y save me some time and you some money!"  Didnt even take him more than a couple of seconds of checking the usability of them to tell me that.

From what I understand, its a common thing umong the 302 Mustang guys to look for the 289 heads, or else they use the expensive Aluminum ones.

Sorry I cannot be any more help. I think a mashinists that does a lot of SB Fords will be much more informative than I could be.