jug, and piston help

[shortboxbs]

hey guys, new to the forum. i just picked up a blaster the other day for near to nothing. the engine is free, and the previous owner said he thot it had been bored as far as it cud. i pulled the jug and it almost seems to me that it has a sleeve in it. the piston has these two numbers on it. 0816a, and 573n06750. i dont know if this will tell any of you guys something bout it or not. my plans are to overhaul the topend and start tearing it up lol. ill enclose a cpl pics and maybe someone can tell me anything at all. all my mics are at work and i havent measured it yet, but will soon. just kinda courious where im at. thanks guysI:I

 

[stephen12091985]

the piston size is a 67.50mm so its gota about one or two more bores left on it unless the cylinder is scared really bad

 

[brandoz28]

yup, unless its really bad off you've got at least 1 if not 2 overbores left

 

[shortboxbs]

cool thanks, what size should i look at? 68 mm? or is the a 67.75?

 

[brandoz28]

piston size 67.75

 

[stephen12091985]

take ur cylinder to a machine shop first and let them tell you which size to go to if the cylinder is really scratched up

 

[shortboxbs]

also, what are the measurments before i even need to bore it. maybe a good honeing and some rings?

 

[shortboxbs]

k, ill run it over to my buddys machine shop. its not even really scarred up. i just lpulled the jug with the thoughts of freshening it up with some rings.

 

[stephen12091985]

the piston size u have now is 67.5.you will either be going to 67.75mm or 68mm

 

[shortboxbs]

well heres an update. the cyl is at the outer limits for the 67.5 bore so the shop is gonna hone it out to 67.75 the question i have is, is there any fear of the engine overheating going out to this size? and is there any jet size i shud start with other than stock?i ordered a wiesco piston set for 90$ and a completes seal and gasket set for 58$. id hate to sieze it up doing a chop test with the stock jets after the work and money. any other advice on where to start from here would be great, thanks guys.