Anybody bore 386

[97warriorrider]

Hey i was wondering if anybody has bored there motor out to 386? How many over is that? Isnt it a .080 over?

 

[jasonp]

.80 over is 366cc. All the bigger you can go with out re-sleeving the cylinder and having the cases machined out for the bigger sleeve.

 

[97warriorrider]

hmm..i need a new head and on ebay there is a cylinder the is bored 386 and i want to get that if i knew what bore it was b/c i would like to put a new piston in it if i buy it..reason for needing a new head is because where the bolt goes through the head for the motor mounts it broke off and busted the head.

 

[dave76]

Yeah 0.80 over is equal to 2mm or 85mm piston. Going to a 87mm piston gets you to 383.5 and 88mm gets to 392cc. The 386 your talking about is an 83mm bore and 71.5mm stroke, or basically a Bigbear 400 bore stroke ratio.

 

[97warriorrider]

ok..so when this person bored there head did they have to put a new sleeve in?

 

[dave76]

You can go as high as 85mm or 366cc on the factory sleeve, you will need and after market sleeve and a case bore to fit the bigger sleeve in for anything bigger.

 

[97warriorrider]

Alright well then he must have pressed in a bigger sleeve..i think im just gunna save up the hotrod stoker kit.

 

[dave76]

Thats what I would do, you have to crack the cases to press in the bigger sleeve so why not just get the Hotrods and stroke it. BTW a Hotrods +7 mm stroker crank is way better then putting the huge bore in the motor, because the longer stroke will slow the piston speed down, creating less wear and more torque

 

[97warriorrider]

yeah..and you dont have to machine the cases just bore the cylinder