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Hey all,

I am changing over my valve guides to supertech bronze valve guides. Does anybody know if these guides have to be reamed? On the packaging it says they do however the machine shop I talked to said they almost never ream a guide that is for a specific valve only if it is a custom fit. The packaging saying it needs reaming. Is this only to cover supertech incase there is a defect in one of their guides and it isn't a consistant size? Supertech part numbers GDE-NSR6-I on the intake and GDE-NSR7-E on the exhaust. I am going to get the machine shop to check the clearance anyway but just wanted to find out what is the go as I don't want to get charged if it does not need to be done.

Thanks

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If your valves fit inside your guides now and have specified clearance, then you will not need to ream them. If the machine shop installs the guides while the head is hot, and they do it properly then they will have no problems, donw right the guide will not distort or change size.

If your valves fit inside your guides now and have specified clearance, then you will not need to ream them. If the machine shop installs the guides while the head is hot, and they do it properly then they will have no problems, donw right the guide will not distort or change size.

not my experience...our guides are always 'finished' after instal. A lot of people do it differently as correctly tooling up to do them the right way costs $800. We will stick to doing it our way...we have never had a problem with the valve picking up on a guide or also an issue with excessive clearance.

Edited by DiRTgarage
Pretty sure when i spoke to the guy at portflow the distributor for supertech he said they had to be honed after fitting as they squish when installed. I have the supertech valves and they are a pretty nice thing.

yes that is what we have noticed. A couple of engines that we know of have had issues straight fitting them.

You need to finish them once they're fitted. The interference fit in the head is only on part of the guide and will squeeze them in where they have interference. I hone them but it's a fairly expensive setup, there's a few grand tied up in Sunnen valve guide honing gear.

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