Valve guide material

[Dave.Thomas]

Hi, I’ve had no response to a shout for NH alloy head valve guides, so I’d better get some made.
Should I stick with bronze, or is steel better ?

[keith.mettam]

Hi Dave,
Feked.com show them listed again:-
https://www.feked.com/engine-and-transm ... es-guides/
Regards,
Keith

[will_curry]

I've always chosen bronze over cast iron or steel for alloy heads because I
was told many years ago that it was the thing to do as the bronze had a
coefficient of expansion more like that of the alloy than the other materials
and thus bronze guides were less likely to work slack in the head.

Given what yours is used for that might be important.

At one time someone was offering to sleeve worn valve guides in situ in
the head - that might be worth pursuing although I can't remember who
it was.

[Dave.Thomas]

Thanks guys. Feked wasn’t on my radar, I don’t think I’ve used them before. I’ll just go with the bronze then. Chris at Autocycle Eng was trying to tell me that steel were getting used more now, maybe he was getting confused with iron heads ?
Cheers

[Simon.Gardiner]

I think SRM are quite keen on doing 'colisbro' inserts for worn valve guides, possibly a few more folks are going down that route now as well 'cos SRM have been doing it for ages.

I think I've seen an alloy head that had a cast-iron valve guide in it but I've never come across anyone who's thought it to be a good idea....

SG

[david.anderson]

Have you thought about a k-liner. I am aware of a lot of worn guides being refurbished with a k-liner, and it is a simple job for a machine shop. Apart from that if you are going to make them, the most favoured material is Ampco 45 which is an aluminium bronze or Cosilbro which is a silicone bronze.
David

[nevhunter]

It's common in cars. Less likely to move around than bronze. A few cars run valves direct in the alloy. Nev

[Roger Gwynn]

Yes bronze is used because it is closer in expansion to alloy and iron, rather than steel. We used to fit iron guides in triumphs that used to wear the guides out very quickly but they had to be a couple of thou tighter to stop them coming loose.