overbore

[comptoncj]

does anyone have a rough price on overboring a 1300 to take 1200 pistons? it makes 1400cc long stroke ??

cheers :)

[mowgli]

ring a local engineering shop. they will also need to pocket the pistons out a bit..

[comptoncj]

ok will do mate, aren't 1200 pistons pocketed then ?

[mowgli]

they are a bit, but the extra stroke means that if you put them in as standard, you'd have about 12:1cr, I had about 5mm of depth machined out of the pistons. the crown of the piston has a concave dish with valve cutouts. i had the machinist go out to the edge of the concave & then remove 5mm from the top of the piston to the centre. I also had him radius it. then engine i had did 90000miles, then i sold it

[comptoncj]

oh right, i see yeah 12:1 is a bit much, im looking for about 10:1 maybe a little bit more, would have to run it on 99 fuel though, im aiming for 130+ bhp out of this creation, my uncle managed 140+ out of his 1400 race engine (1300 bored out) :)

[mowgli]

can't you just get your uncle to help out on this one then??

[comptoncj]

could do but wanna attempt it myself, and the chap that did his engineering work no longer exists i dont think,