Here is how ours look. No leaks. Is your an older set of heads. We have had this set about 3-4 months.
Why would the manufacturer machine the head that way? Just unnessesary work, which will cause a leak, IMO.
Found a problem with Pro Comp heads
Thread Starter
Melting Slicks
Joined: Feb 2003
Posts: 2,529
Likes: 27
From: Auburndale Florida
2025 C2 of the Year ('64-'66) Finalist - Unmodified
St. Jude Donor '03-'05-'06-'07-'09
Found a problem with Pro Comp heads
Can't get the valve covers to stop leaking oil on my new engine. Making a mess of all my detailing and painting of the engine and compartment!!!!
After 2 sets of valve covers I figured it out...the area around the bolt or screw holes is different than stock GM heads. GM heads have a flat surface for gasket contact all the way around the hole for a good seal. The Pro Comp heads do not...see pic. The bolt is exposed to the oil and not sealed like stock heads. I think the oil is comng up around the bolts and out on the covers and on to the exhaust manifolds. Now to figure out a fix....maybe O rings under the reinforecements and again under the bolt???
Are other aftermarket alum heads like this? Any suggestions for a cure would be appeciated. Thanks, Mark
After 2 sets of valve covers I figured it out...the area around the bolt or screw holes is different than stock GM heads. GM heads have a flat surface for gasket contact all the way around the hole for a good seal. The Pro Comp heads do not...see pic. The bolt is exposed to the oil and not sealed like stock heads. I think the oil is comng up around the bolts and out on the covers and on to the exhaust manifolds. Now to figure out a fix....maybe O rings under the reinforecements and again under the bolt???
Are other aftermarket alum heads like this? Any suggestions for a cure would be appeciated. Thanks, Mark
Le Mans Master
Joined: Oct 2006
Posts: 7,123
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I see what you're talking about. Not too impressed with the way they cut the heads there. If you're not having to pull the covers to adjust valves, maybe a bead of RTV all the way around the cover sealing area? Clean the mating surfaces with alcohol and RTV all around. Let it cure and see what happens.
Racer
Joined: Dec 2005
Posts: 368
Likes: 4
From: . New Zealand
That's poor design, a fix may be to clean the area good with brake cleaner, put a bolt into the thread to prevent Devcon which you can build the area up with, then when cured file or sand down to the same height. (I'm assuming you have the heads off), if they were mine I would do a weld build up and mill them down to level.
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Thread Starter
Melting Slicks
Joined: Feb 2003
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From: Auburndale Florida
2025 C2 of the Year ('64-'66) Finalist - Unmodified
St. Jude Donor '03-'05-'06-'07-'09
Thread Starter
Melting Slicks
Joined: Feb 2003
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From: Auburndale Florida
2025 C2 of the Year ('64-'66) Finalist - Unmodified
St. Jude Donor '03-'05-'06-'07-'09
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From: Nashville, TN
I have been thrtough a set on my ProComps and it did thee same thing. I bought studs, cleaned them down with alcohol, rtv the studs in sealed up the gaps, put a nice bead around the stud, thin layer of rtv on head and used the Summit's rubber coated steel VC gaskets. Has been two weeks now and haven't leaaked a bit.
Race Director
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Maybe look real close and make sure the valve cover lip isn't hitting head before it compresses gasket? It's pretty common on aftermarket heads. Sometimes it's just on one corner or something.
Sometimes valve cover lips contact intake manifold too and it keeps them from compressing gasket enough.
Those holes ought to do OK if they are deep enough to have some threads to engage.
Are these the Chinesse Pro Comps or the *new* RHS heads that are the old Pro Toplines? Big difference in the two heads.
JIM
Sometimes valve cover lips contact intake manifold too and it keeps them from compressing gasket enough.
Those holes ought to do OK if they are deep enough to have some threads to engage.
Are these the Chinesse Pro Comps or the *new* RHS heads that are the old Pro Toplines? Big difference in the two heads.
JIM
Thread Starter
Melting Slicks
Joined: Feb 2003
Posts: 2,529
Likes: 27
From: Auburndale Florida
2025 C2 of the Year ('64-'66) Finalist - Unmodified
St. Jude Donor '03-'05-'06-'07-'09
I have been thrtough a set on my ProComps and it did thee same thing. I bought studs, cleaned them down with alcohol, rtv the studs in sealed up the gaps, put a nice bead around the stud, thin layer of rtv on head and used the Summit's rubber coated steel VC gaskets. Has been two weeks now and haven't leaaked a bit.
I AM SO TIRED OF THIS CHINESE CRAP. All the BS repo parts at outragous prices, poor fitting, poor performance, shoody quality and on and on ....Tired of spending hours to make things fit or look decent....doing someone elses job.
I just sent back the distributor cover and 2 side pieces of ignition shielding to Corveete Central. Little or no chrome on the side pieces and the top was wavy from the poor stamping....problably $20 in real money that is bought for $160. Not to mention I had to pay the freight both ways..................
Veteran
Joined: Oct 2005
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From: Nashville, TN
Believe me I know, RHS got into Nickels Performance today for selling these as RHS. Then they called my builder and both are blaming it on each other. The good news is a set of new 195cc CNC'd Canfield heads are on the way. They are giving me full credit for the ProComps. More then I wanted to spend but at least I am giving back to my state.
Race Director
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From: Foxfield CO 1970 Convertible
Veteran
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From: Nashville, TN
Also according to RHS D McCarver they would say either RHS or Protopline at the end or under the Valve Cover. Also anything stamped PC3001-xxxx-xxxx above the exhaust port is a ProComp. Unfortunate in how I know this. I think the new RHS say ProAction under the VC.
Last edited by King Lear; Jan 30, 2007 at 12:04 AM.
Race Director
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From: Taylor Michigan
I`ll try. First get a good set of gaskets. Several brands and one is probably not better than the other. I prefer the Felpro rubber/cork combination overhead gaskets. These are soft and flexible whereas plain cork will brake. You do not need any high dollar gaskets as I reuse mine over and over. Naturally clean valve covers, right! Here is what I found to work. 3M weatherstripping cement part # 08001. Run a thin bead of this cement completely around the valve cover and let it set up tacky. Drop the gasket into the cover and secure it until the cement drys. Wrenches, boards, any thing to make the gasket secure in the cover. Now go do the other side the same way. You have now glued them into the covers and with some bearing grease on the gasket surface to prevent sticking you will be able to reuse them over and over.
PS, All my racing and street engines are similarly situated. Some sets are several years old and still reusable.
PS, All my racing and street engines are similarly situated. Some sets are several years old and still reusable.
Race Director
Joined: Nov 1999
Posts: 10,643
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From: Foxfield CO 1970 Convertible
Yes. They have "ProTopline" embossed in the center of the head...with a checkered flag like their logo. I've had zero problems with mine...
