Help identify aluminum heads

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What is the issue with one valve seal. Is it smoking at start up? Using oil? What was done to determine which one is bad? or that it needs a valve seal at all?
 
Pretty straight forward job to do with air pressure holding the valves closed. Have to be very careful not to drop a valve keeper down into the head or an oil drain back hole. Judging by the smallish cam i doubt you will have a heavy valve spring to deal with.
 
Tech857 said:
What is the issue with one valve seal. Is it smoking at start up? Using oil? What was done to determine which one is bad? or that it needs a valve seal at all?
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I haven't used the car enough to experience any issues yet. The previous owner told me out of no where from time to time the spark plug in that cylinder will get covered in oil and foul. I'm pretty sure he spoke to the engine builder and was told it was a valve seal that needed to be replaced
 
Tech857 said:
Pretty straight forward job to do with air pressure holding the valves closed. Have to be very careful not to drop a valve keeper down into the head or an oil drain back hole. Judging by the smallish cam i doubt you will have a heavy valve spring to deal with.
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This, might want to stuff paper towels any where a stray part might go.
And the rope thru the spark plug hole works well too.
 
Took awhile but finally pulled the pan & confirmed its an eagle 4.150 stroke crank. So I guess that makes it a 493 but what does that do to the compression?
 
Strange. All I can make out on crank is the eagle and the last digits of the part which are 06-075 . . . Close but doesn't match up to any current eagle part numbers. Going to call them Monday, stay tuned
 
GREEN GHOST said:
Took awhile but finally pulled the pan & confirmed its an eagle 4.150 stroke crank. So I guess that makes it a 493 but what does that do to the compression?
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Well, the longer the stroke, the higher the the compression for a given combustion space size.
As PRH said, until the heads come off and some actual measurements are made, we won't KNOW what the compression ratio is .
However with a little more info, we could make an educated guess. The first thing we would need to know, that we don't know, is the compression height of the pistons. Call mahle with the work order number if it's not on the box. They will know.
That would at least give us a reasonable guess as to deck height. Consider: a flat top engine like yours at zero deck, with true 75cc heads is probably a 12 to 1 engine. If the pistons are .150 down in the hole, (as some oem 440 pistons were) it would probably be a mid 8 to 1. But without some idea of deck height, no calculation will be any better than a complete WAG, wild *** guess.
 
33IMP said:
Well, the longer the stroke, the higher the the compression for a given combustion space size.
As PRH said, until the heads come off and some actual measurements are made, we won't KNOW what the compression ratio is .
However with a little more info, we could make an educated guess. The first thing we would need to know, that we don't know, is the compression height of the pistons. Call mahle with the work order number if it's not on the box. They will know.
That would at least give us a reasonable guess as to deck height. Consider: a flat top engine like yours at zero deck, with true 75cc heads is probably a 12 to 1 engine. If the pistons are .150 down in the hole, (as some oem 440 pistons were) it would probably be a mid 8 to 1. But without some idea of deck height, no calculation will be any better than a complete WAG, wild *** guess.
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Mahle , eagle , & milodon are all on the list for a Monday morning call
 
Had to step away from the dart for awhile & just getting back into it now. . .found some specs on the block, deck height 10.725
 
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