nailhead boring!

I searched and didnt find it but im getting my 65 nailhead rebuilt and found out it had already been bored out 40 over with crank 10/10. Im wondering what the max bore on a 401 should be for a street car application if it matters

 

At this point you need to sonic check it before going anything over 60. And I'd sonic check for that.... Does it need to be bored again?

 

Exactly, not every overhaul is a bore and hone job. First find out what you got then decide what to do with it. if the cylinders are round and straight and within tolerance it is just scuff n ring job. Same with th crank of its round and within tolerance its just a matter of putting new inserts in parhaps polishing the crank.

On the crank if you are close to being in tolerance and it is round you donot have to buy inserts in increments of .010. On the block if you are on the outer edge of tolerance there are also a couple of tricks that can be done, but first find out if it needs to be machined then decide what to do with it.

 

Let's hear more about this.
Inserts in undersizes other than in increments of .010 is new info to me.

 

We did a Methanol Injected 311, that made 917 h.p, .......definately not boring.

 

Still boring...

 

Nailheads are anything but boring!

 

The engine does have to go 60 over with one cylinder being sleeved and the crank was already 10-10 and will now be 20-20

 

I have a 322 that is bored to .100 - if that is any help. At least the early nails are pretty thick !!