[Healeys] Mike Salter. Bronze guides

[Bob Spidell]

Millions of opinions; just google 'bronze vs iron valve guides.' 

Generally, bronze guides have less friction, but that's probably not an issue for a stock build. Also, bronze tends to cause less galling of the valve stem. Note using bronze inserts in iron guides is popular. Note also that if the guides are reamed too wide you'll get too much oil down the guide which can 'coke' and cause sticking; this happens fairly often in piston aircraft engines which, like motorcycle engines are air-cooled and usually (I THINK) use bronze guides. 




what's the advantage to bronze guides? 

Ira Erbs 
Portland,OR 
1959 BN4 100-6 
with BT7 engine and disk brakes. 

On Wed, Jan 27, 2016 at 8:07 AM, Bob Spidell < bspidell at comcast.net > wrote: 



I think the 'trick' is to ream extra clearance in the guides (esp. the exhaust). We didn't give specific instructions to the guy who built my head, but he is a race engine builder and probably knew to do this. 

Or maybe I just got lucky. 

Bob 



I have used bronze valve guides and have always had trouble with them, I've made them work but it's always been a hassle. I don't do it anymore. 

Cheers, Henry Morrison, Albuquerque, NM 




Sure wish I'd read that article before I put 110K miles--still going strong--on my BJ8 with stock iron head and bronze valve guides. 

Bob 






Great article and sleuth work on figuring out why bronze guides and cast iron heads are a bad idea in this month's Healey Marque Magazine. Love the technical jargon, ie all black and yucky. Good job explaining all the technical stuff. 
Cheers 

Mr. Ira Erbs 
Portland,OR 







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