Can somebody run Bow Tie block numbers?
 

I have a 502 mag that was manufactured in 1990. This is not a Merc it's a Bow Tie. I was told that GM ran out of blocks to supply Merc so they gave them a higher performance version of the 502 and kept it quiet. This motor has some different stuff too like bigger oil cooler, brass Jabsco sea water pump and such. I have no clue and am no gear head. I got these numbers off the back of the block stamped above the bell housing. Can somebody tell me what I have. #10051107

Thanks
Bryan

Re: Can somebody run Bow Tie block numbers?
 

http://www.mortec.com/bbc.htm
10051107...454...............4-bolt, Bowtie, MkIV, 9.8" deck, siamesed cylinder barrels, 4.25" semi-finished bores, can be bored to 4.500"

Re: Can somebody run Bow Tie block numbers?
 

Shouldn't there be either 8.2 or 7.4 cast in raised numbers on the side of the block to be able to reconfirm whether it is a 502 or a 454?

My '94 502 had the 8.2 casting.

Re: Can somebody run Bow Tie block numbers?
 

That block casting number should have a raised "bowtie" emblem on the side of the block.

Re: Can somebody run Bow Tie block numbers?
 

Thanks I will look for a Bow tie and or 8.2 or 7.4. The Merc tag has is not welded on it is screwed in, like I say this wasn't an original merc the tag # is D602746 (502 Merc)

Re: Can somebody run Bow Tie block numbers?
 

It runs great now it's got a Dart high rise manifold, Stainless Marine exhaust, 830 Holley but I don't have a clue of what's inside. I wish I knew so if I ever want to do anything else I'd know what to order. It's a 270 Baja the Holley is not marine so we re-jetted it to 500hp carb specs and I picked up 1.6 mph and better idle. I've gotten 67.8 mph gps @ 4950 rpms I didn't think that's too bad.