Hey Guys,

I have been doing some research on this build up and I noticed the CNC 345 version of these -1 heads it recommends a 4.375 bore. Why is that? Will the valves contact the cylinders? Would this hold true for any -1 with a 2.25 valve? My setup has a 4.350 bore. I don't need the 345's but I have seen a few sets of heads available but they all seem to have big valves.

Thanks!

Mine is 4.39 with the 2.25vales in the -1's with no problem

Depends on the valve lift. You might need to notch the bores like the old Max Wedge engines. Always a good idea to mock it up before firing the engine.

Hey Andy,

I am sure you don't recall, but years ago I bought a welded stroker crank from you to build a 499. Regardless, the motor is for a street engine. It will have a solid roller but certainly nothing exotic regarding lift. I just don't know if I need to chase the smaller valve head or if the larger valve will work. Any input is appreciated.

Any other experiences or thought?

Thanks!

It has been so long ago since I run a stock 440 that I can't remember if it was a .040 or .055 over engine,but I put them on with no problems on a new build.I would like to tell you that them being 440-1 heads they were made to bolt on a stock bore 440 but I have never done it so I won't,but you can call Indy and they will tell you.They have always tried to be helpful and the one time they could not answer my question they told me they would have Russ call me and believe it or not he did.