502MAG EFI motor freshen up
#13
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High end main bearings - $100
High end rod bearings - $100
cam bearings - $40
Refresh at machine shop $150
Set of high end rings - $100
Timing chain and gear set - $75
Total $565 for a brand new bottom end on your engine using the best parts available.
Peice of mind that you don't have to touch it for another 450 hours. - Priceless
By the way. THat is using the best of everything. You can probably put it back stock for less than half that and still be ok.
Vavle job and springs should only be another $300 a side - max.
Moral of the story, if it is out of the boat, you might as well tear it down.
High end rod bearings - $100
cam bearings - $40
Refresh at machine shop $150
Set of high end rings - $100
Timing chain and gear set - $75
Total $565 for a brand new bottom end on your engine using the best parts available.
Peice of mind that you don't have to touch it for another 450 hours. - Priceless
By the way. THat is using the best of everything. You can probably put it back stock for less than half that and still be ok.
Vavle job and springs should only be another $300 a side - max.
Moral of the story, if it is out of the boat, you might as well tear it down.
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#15
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I totally agree with the other responses, while it's out, do it all. I think Jeff's number are a little low for the refresh. Parts numbers are correct. The biggest problem I have seen is that the vast majority of the 502's won't go back standard bore with 400 hrs. They run very little piston to wall clearance. By the time you hone the cylinders and get them round again, you have opened the bore to much. GM recommends no more than .0045 clearance. If you run to much clearance, you will break a piston skirt because of their high silicone content. DO NOT put new rings in a cylinder that is not honed to perfectly round. They won't seal worth a damn. I would not put it back without doing the bottom end while it is out, that just seems like a waste. Hope this helps and good luck, Eddie.
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You can get a complete rotating assemblie for the bottom end using all high end stuff (good to 1000hp) for under $2000 delivered.
My prices earlier didn;t include labor, but I was just trying to make a point.
Good luck with your project.
My prices earlier didn;t include labor, but I was just trying to make a point.
Good luck with your project.
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Eddie