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new stealth heads

mac

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just got back a set of stealth heads from the machine shop. now if i just had the car out of storage to work on. hoping that the increase in compression and better air flow will help with a few more ponies and some torque. :banana: guy from the shop says to stay near 10:1 compression, so with stock head gasket it will be 9.9:1.
 

moparchris

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moparstuart said:

I always take assembled heads apart and clean them, lap the valves in, check spring pressures, valve height, and check retainer size and keeper contact. You would be surprised what you find, pretty minor stuff that would be a major problem if you were to bolt them on and run them. I have yet to find a set of heads that didn't have aluminum shavings on top of the valves. :cents:
 

ACME A12

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moparchris said:
moparstuart said:

I always take assembled heads apart and clean them, lap the valves in, check spring pressures, valve height, and check retainer size and keeper contact. You would be surprised what you find, pretty minor stuff that would be a major problem if you were to bolt them on and run them. I have yet to find a set of heads that didn't have aluminum shavings on top of the valves. :cents:

I've even heard of brand new aluminum Eddys in which the valves didn't even mate to the seats... :eek:
 

mac

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the heads were gone through. springs checked, guides honed to size, valves lapped, new locks, and new seals. even had them vacuum checked and cc'd.
 

moparchris

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mac said:
the heads were gone through. springs checked, guides honed to size, valves lapped, new locks, and new seals. even had them vacuum checked and cc'd.

Sounds like someone is ready for some killer burnouts!
 

mac

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moparchris said:
mac said:
the heads were gone through. springs checked, guides honed to size, valves lapped, new locks, and new seals. even had them vacuum checked and cc'd.

Sounds like someone is ready for some killer burnouts!

that should be a written guarantee, i hope it will help.
 

IQ52

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So what would happen if you took an OOTB set of Stealth heads and........
Stripped them
Put them on a flowbench
Checked valve stem diameters and valve heads for roundness
Checked valve guide clearance and corrected if necessary
Back cut the valves
Do a rough performance valve job in the heads and set the valve installed heights to + or - .001"
Do a combustion chamber, bowl and port clean up
Do a finish valve job
Re-flow the cylinder heads
Note any big flow discrepancies and send them back to the grinding bench
Re-flow the heads
Grind extra pushrod clearance along the intake ports for 1.6 rockers and/or 3/8" diameter pushrods
CC the heads
Mill the heads
Measure the valve springs for proper pressure
Clean the heads and components, lube the guides and valve stems
Assemble the heads and set the spring installed heights

What would incidentally happen to the flow rates of those heads? Hmm? Well........

Lift.........OOTB IN/EX.........Prepped IN/EX
.100............70/57................75/59
.200..........148/114.............152/128
.300..........210/159.............216/172
.400..........248/193.............263/208
.500..........268/218.............288/236
.600..........277/234.............299/256
.700..........278/244.............305/268
 
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