Bought a set of '70 service replacement heads part # 1240149 (small valve). Originally born with 69cc combustion chambers, now shaved to 64cc and converted to big valve Stage 1 specs. Bought a set of Stage 1 valves, ( originals were too thin) and Stage 1 Plus springs. I've lapped the newish valves in and am moving onto the springs. My issue is that the guides that are installed in the heads are smooth shanked, so to speak not at all like the guides in an old set of '71 heads I have. 1st picture is of old '71 head and guide. Second picture is Stage 1 head /guides Notice intake guide is smaller than exhaust guide. Last picture is Stage 1 head with valve stem seal on exhaust valve. Seals are from a Felpro complete gasket set. I'm not sure what to use for valve stem seals. The Felpro ones only fit the exhaust guide and I'm not confident that they will remain there during use. Not only that they interfer with the interior valvespring so they are not an option. Jim
There's are 2 common size of valve guide OD's, .500" and .530". In either case I would run the blue Viton type seals like Comp Cams and many others sell.
Meaaured guides in Stage1 head: OD- exhaust-0.625 OD-intake- 0.502 I'll peruse the TA catalog and see what they have. Maybe I'll givem a call after the holiday....appreciate the reply....JIM
Found Comp Cams 11/32 / .500 viton seals at Jegs . Installed OD looks like they will work, not interfer with internal double valve spring. I think they will be good for the intake guides. Still looking for exhaust seals with an OD that'll work with the dbl springs.....JIM
Measure your valve stems, they look like OE type 3/8 not 11/32. I wouldn't get too hung up over seals for the exhaust if clearing inner springs is going to be an issue. Maybe get the top of the guides tapered so excess oil runs off and be done with it
What is the small OD of the Exh guides? You can buy cutters that load in a hand drill to resize the Exh guides to .530" or .500", there like 90 bucks and then you can run the needed positive type seals ( like the Viton ones) that a performance motor should have on them . If you go this route be sure to lube the cutter guide shaft with a few drops of oil.
Valves are .343 = 11/32 Exhaust guides measure .625 to .628 OD and are smooth, without detents . See pic 2 and 3 above. I am starting to think that these heads were run without exhaust valve guide seals. If running without seals on the exhaust guides is an acceptable option, I may do that. Jim
Some history on heads. I purchased these from Buickrat and this is a copy /paste of a conversation with him: _________________________ If those are the 0149's you got from me, those were a max effort nhra stock legal head. Herb looked at them and said Charlie Evans may have done them. No telling what cams they were running, but it musta needed a Lot of spring. Remember, this was eighties/early nineties, maybe earlier. Prolly had to cut the guides to clear whatever springs were available. Fast ramp cams were popular back then, 'cause stock buick motors really liked them. Hard on the valve train, though. You may have to measure the od on those guides and ask a machine shop if they can get ones that will fit. Or run them without. If the valves are nice and tight in the guide, you shouldn't have an issue. _________________________________ Jim
Finished my winter upgrade: Stage 1 heads, 64cc NOS McCord steel head gaskets .020, Lunati SPX2 Cam, TA SP1 Intake 4150 TA adjustable pushrods Comp Cams ProMagnum lifters Thanks for replies, JIM
Its all together. I used Comp Cams Viton Seals on the intake guides. No seals on exhaust. Cam/lifters mated with 20 minute break in, using outer springs. Inner springs installed and waiting on April 2nd, ( opening day at NEDragway) Jim
