do I need to sleeve this engine?

[Paul]

I just took the heads off the 401 I want to put into the Warhorse, and it seems the motor has already been bored .040 over. I have read that 401's have fairly thin cylinder walls, and that too much boring can lead to overheating problems. Should I have this block sleeved and start over again? I'll bet it's expensive.

[bigblack'74]

mine(401) was bored to .030 and it was gonna have to be sleaved..so i parted out and forgot aBOUT IT..oh it aint cheep 75 per cylinder here

[andy d]

ok, if you check the cylinders for taper what do you come up with? how much ridge is there? you may get lucky and a re ring may fly.

[lindeleasley]

Sleeving is typically between $50 to $100, per cylinder. Yes it sounds expensive, but what you get is a rebuildable block, that you can always rebuild at stock specs. Resleeving is always cheaper, since you've already had the machine work done.

Another advantage is a little bit quicker break in period, because the sleeves aren't going to have as much nickel content as the stock block will.

If you're concerned with the sleeves being tough enough to withstand everyday driving/wheeling, don't be. The technology has been used for years in big diesels, and in 6000+ HP top fuel dragsters. Makes for a very easy, quick rebuild.