Should I sell my good heads?

[NE57]

I have two sets of 392 heads.

1) completely prepped with extra large intake and exhaust valves and race springs, exhaust crossover filled, tube seals, etc., milled to 97cc chambers. Could get 10.5:1CR with shelf forged pistons but they would need valve reliefs enlarged or get custom forged pistons

2)bare heads that have only had the guides replaced. would need all the other usual work/parts, has most of the stock-size valves in stainless steel. Not sure about exh seats. Stock valve sizes would allow shelf forged pistons easily.

I hear differing opinions on exhaust valve size for street motors, unblown. I suspect the good heads were setup for blown. They are what they are, I bought them already done. The bare heads could be setup whatever way is best suited for the street.

If the good heads fetched a large enough price, there might be enough money for forged pistons and the head rebuild...two birds one stone, maybe little or no extra cash needed? I see comparable heads on ebay asking $2K but they don't seem to sell fast. Would $1500 be a more realistic sum? I have the original recipet for the work done by the machine shop 5 years ago,, $1700.

What do you think? Ofcourse I would have the bare heads magged befoe making the final decision.

[mart]

Unless you can get a lot of money - a bunch more than
you'd in spend in doing up another set, I'd be very inclined
to keep the heads and use 'em. The 97cc chambers
and 10.5 to compression ratio with off the shelf
pistons sounds sounds about ideal. Fly-cutting the valve
reliefs in the pistons to clear the over-size valves is not
a big deal - and while you don't actually *need* the big
valves on the street, they won't really hurt anything
either. Off-idle torque might - or might not - be a bit
less, but with the cubes and compression you've got,
if it is, it probably won't be down by enough to notice
or worry about - and the big valves should add a bit of
power and revability on the top end.

mart
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[oldngood]

I have two sets of 392 heads.

1) completely prepped with extra large intake and exhaust valves and race springs, exhaust crossover filled, tube seals, etc., milled to 97cc chambers. Could get 10.5:1CR with shelf forged pistons but they would need valve reliefs enlarged or get custom forged pistons
2)bare heads that have only had the guides replaced. would need all the other usual work/parts, has most of the stock-size valves in stainless steel. Not sure about exh seats. Stock valve sizes would allow shelf forged pistons easily.
I hear differing opinions on exhaust valve size for street motors, unblown. I suspect the good heads were setup for blown. They are what they are, I bought them already done. The bare heads could be setup whatever way is best suited for the street.
If the good heads fetched a large enough price, there might be enough money for forged pistons and the head rebuild...two birds one stone, maybe little or no extra cash needed? I see comparable heads on ebay asking $2K but they don't seem to sell fast. Would $1500 be a more realistic sum? I have the original recipet for the work done by the machine shop 5 years ago,, $1700.
.

use the "done" heads, but change the springs to match your cam (you don't need "race springs" for a street cam, they will have too much pressure), and buy or have pistons machined for 9.5 CR for today's 93 octane pump gas. Sell the "bare" heads and any spare pieces you have, if you need cash. It's always cheaper in the long run, to keep the "done" stuff for yourself and use it- because parts/machining prices always go up over time, but head core prices have levelled off, or even gone down. In today's market you won't get a lot for your "done" 392 heads, I doubt you'd even get $600 for them, let alone $1500-$1700, the market just isn't there for 392 heads.