As always, please forgive me if this is a dumb question... the ports on my heads have been opened up resulting in the vale guide being angled at the port surface. The performance shop said he can't cut the valve seats as he uses a tapered pilot. Since almost nothing is impossible, the question becomes how difficult is this, and what kind of equipment is needed to do this job?

Don't understand how opening ports changed your valve guide. Did they re-cut valve seats?

We remove the valve guides port the heads and then reinstall the guides, a valve guide should not be cut on at all


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Im not a machine shop guy so jamie or mighty mouse feel free to correct me if i'm out of line, but i'd be a little leary of using a shop that could not figure this out.

Taking the guides out is a little dicey. The press fit gets looser. That's why on cars they sell oversized guides. They don't sell them for Briggs I'm sure. I had to knurl one to make it hold and that's really a "rig".
You don't need to take them out to do head work.

When u machine the heads with the guide in you are lessening the stability that the guide was built for. Allowing more movement in ur valve. We've seen it in heads that are ported with the valve guides still in place and cut down with the head when porting. But hey I've seen it 100s of times


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Best way is to knock the valve Guides out with the proper tooling, perform you machine work and porting, then either bevel or done the guides for good air flow

I meant to type dome instead of done. Lol

It looked like you were talking in third person...lol

The integrity of the valve guide is compromised with what you have described, but like take'em said, it's done all the time, whether it right or not...
What he needs is an expandable valve guide pilot - yes, it takes more time to use these than a tapered pilot, but it uses more middle to "top" end of the guide, rather than the "bottom" end as a tapered pilot - and they are not cheap - I think the last one I bought for my Sioux set was around $100 (that's for each size needed), but IMHO, you get a more "true" fit/alignment to the guide with these vs the tapered pilots.

Thanks all for the knowledge and experience on this, makes complete sense to me. Not happy about loosing a part of the valve guide but this was done by someone else. I'll prolly run with it until season end and then see about modding my stock heads.