Help identify 5.7 longblock serial#

a70eliminator

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Bought an 86 Sea Ray 210 from a dealer & was told previous owner had a brand new longblock installed & it was advertised as 300hp stroker 5.7 lol.
The motor performs well.
While changing the oil today noticed this seriel number plate, side of block opposite the stater.
Is there anything to decipher from this number? Im wondering if it has a roller cam and or is a stroked 5.7 ?
 

Fun Times

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Unfortunately posting photos isn't really working well at the moment and you should see a banner type notice at the top of the forum page with a little note regarding the situation.

What is the full number of the serial number you found near the starter? Might be easier to just type it out so we can try to help out if at all possible.
 

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Scott Danforth

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is it the little round heat tag? those are overheat indicators that melt and fall-off if the motor is ever run hot.

is99ht_2012.jpg
 

Scott06

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Exactly this!
All the common rebuilders like Jasper, ATK, Blueprint Engine etc similar companies that sell through Summit, Jegs etc use them on their engines.

You should be able to tell if it is a roller by the block casting number
 

a70eliminator

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Ok..its not Jasper's tag nor Michian motorz.. can't quite make out the cast numbers, didnt know they could identify much, ill try again thanks
 

Scott Danforth

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Ok..its not Jasper's tag nor Michian motorz.. can't quite make out the cast numbers, didnt know they could identify much, ill try again thanks
the casting numbers on the back of the block just above the flywheel housing boss is huge
 

Scott06

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Bought an 86 Sea Ray 210 from a dealer & was told previous owner had a brand new longblock installed & it was advertised as 300hp stroker 5.7 lol.
The motor performs well.
While changing the oil today noticed this seriel number plate, side of block opposite the stater.
Is there anything to decipher from this number? Im wondering if it has a roller cam and or is a stroked 5.7 ?
Ok..its not Jasper's tag nor Michian motorz.. can't quite make out the cast numbers, didnt know they could identify much, ill try again thanks
if it runs well and you know what parts to order dont sweat it too much. I took a 4.3 mercruiser used most of accessories wiring fuel pump etc and swapped in a 5.0 so I dont have a merc serial number.

If you get the casting on block I think it would also say 5.7 or 5.0 back there depending on displacement. Don't think you will be able to tell stroker yes or no with out dissasembling the engine as a 383/6.2 (GM not merc 6.2) is a 5.7 block with a longer stroke crank originally from a SBC 400 cu.

Do you have 12 or 8 intake bolts . Im assuming at 300 hp you have a vortec 5.7 which would be 300 hp or so.
 
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