302 heads

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Jan 4, 2010
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I have a 71 coupe that needs the valve seals replaced. The motor is not the original and it has an Edelbrock performer cam and intake. It also has headers with flowmasters. What I was wondering was, since I need the heads done, is there anything I can do to get more performance from them without spending a lot of money or is it even worth it? any help would be appreciated.
 
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is there anything I can do to get more performance from them without spending a lot of money or is it even worth it? any help would be appreciated.

Yes! Port-match the exhaust to the manifolds/headers, and remove any Thermactor bumps from inside the ports. It'll feel like you got a better cam. You can do this yourself in a couple hours, I did mine.

The exhaust ports of the 289/302 had an adequate design, but in practice there was usually a lot of casting flash around the opening, and the Thermactor bumps added later were so bad you'd think spies from Chevy put them there.
 
Yes! Port-match the exhaust to the manifolds/headers, and remove any Thermactor bumps from inside the ports. It'll feel like you got a better cam. You can do this yourself in a couple hours, I did mine.

He can also replace the valve seals too himself. But if they need guides too................ and seats, & valves, springs.....................might as well buy new or secondhand aftermarket heads. It's a slippery slope with 40 year old heads.
 
If you need to recondition the heads, I would get a quote/price before doing anything. It is likely to cost you a good portion of what a set of brand new aftermarket heads would cost.