I just recently got some pro topline 180 cc heads for a really good price. I have been doing some cleaning up on the ports, just to smooth them out not really open them up.

Anyway, I was about to buy some intake and exhaust valves but when I was looking on summit I realized they don't have any valves with a stem diameter close to what I need.

My valve guides have an inside diameter of .332.

The closest the valve stem diameter is .320 and then it jumps to .341 which would never fit.

The .320 valve stems however are going to be very loose. The clearances should be about .001-.003, right?

Do I have to get the guides replaced to opened up? What does something like this usually cost?

I was already planning to get the heads decked before installing them anyway so I might have the guides done as well.

 

Nevermind I found the problem. It was me. I measured it wrong.

Turns out they are .341-.342 which summit racing does have both. I am looking at getting the .341 due to a wider choice.

I can finally get some stuff ordered.

 

I'd put a couple valves in those heads with checking springs and then CC the chambers just to see what you've got before I'd have anything milled.
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