Hi all.
Im busy rebuilding engine but need some advice.
Block sleeves look good no scratches or visual wear
Should I rebore just for safety or hone and use stock size?

Thanks in advance

Quote:Rebore is not done for safety. The purpose of rebore is *) when the bore is damaged or worn excessively OR *) to fit larger diameter pistons

To determine if rebore is REQUIRED, measure the bore. Instead of visual inspection:
* measure top and bottom diameter for "taper" wear
* measure at 90 degrees for "out-of-round"

Maximum out of round .. 0.2 mm
Maximum taper ......... 0.15 mm

If no rebore is required, you can refit the original pistons after a ridge and hone job


If you need new pistons, consider getting oversize pistons. Going 3mm oversize will gain you 3x more power than a compression increase. See Bored And Stroked

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Thank you ddgonzol for the response.
I'm changing pistons and after reading your post decided to increase 1mm ..something about 77x77 just sounds good
Compression will be lowered for some snail power :)

Just an FYI for the gang; A-series tend to endure monumental abuse (mostly from me) but I used to just check piston to wall clearance and if it was remotely close slap,new rings in......no hone and then almost completely ignore sound break in procedures. When my A12 wore out it had 80lbs of cranking pressure and would still pull 7200 RPMs. When I pulled the motor apart you could visibly see the wear.

Naturally this is the wrong way to do it....................but they will tolerate it.

Tom