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RE THE BAFLES,when used competition head gaskets the baffles are the same thickness of a old after used comp. gasket.so geometry the same as shim gaskets with baffles. I used 302/289 valve sealed,but trimed the umbrella seals1/8 of in. my big concern was and still is was rocker shafts, as with spill tubes in place the end of no spill tube is usually full of sludge. so critical to clean out shafts or replace them.those who wory about draining the oil from heads need not worry
I think cam issues start with 1 end of valve train gets poor or no oil loading up the camshaft.
my 292 is into its 5th year, just did a valve lash and found virtually no wear. no smoke, no lube oil burning. well worth a minor compression drop due to thicker head gasket. I MEASURED A OLD COMP GASKET AFTER BEING USED THE SAME THICKNESS OG THE SPILL PLATES UNDER ROCKER SHAFTS. my opinion is positive valve seals is
to sever and causes guid wear. at rebuild I used a new cam with re surfaced lifters.
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272meteor. I find your statement about positive seals a concern but I feel not a reason to not use them. I used the original style PC white nylon seals starting many many years ago. In one of my racing engines where roller tip rockers were not available (not a Y-Block or Ford product) I found valve guide wear was a problem because of the side pressures of the rocker tip. I designed and made roller shaft and tip rocker arms and the problem was gone. Prior to the new rockers the valve lift was .530” and seat spring pressure was #130. The seals always felt tight. After the roller rockers the valve lift was .610” . As years went on new materials became available which sealed the valves but caused a lot less drag. I understand that a non-roller tip rocker “scuffs” the valve tip and over time and miles causes a lot of the wear especially when higher pressure and lift is used. On a stock 56 cam lift with the stock spring pressure and newer seals I feel this will not be problem and I’m willing to have a seal that will allow less oil into the combustion cycle thru the intakes.
I’ve recently fit the viton seals to my engine with 11k miles and during the work with the tool to get enough clearance between the retainer and valve seal top I was able to check every measurement and mic everything which I’m never sure of a shop doing. On final assembly I could move the valve up and down with what I felt is the correct “drag” on the stem. If I was using a high lift cam with a higher pressure valve spring I might have concern but with stock parts I’m not. Since doing this work my engine it has not run this smooth and quiet in many years.
56 Vic, B'Ville 200 MPH Club Member, So Cal.
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that is great to have roller rockers. truth is most of us are not racing, but refaced rockers(properly via vg machine) withe new rocker shafts and spill tubes blocked will stock 289/302 valve seals will give good service for50 00 to 80,00miles my 292 burns no oil, rockers are quite, I did enlarge the grove in new cam.
good luck with your race engine.
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