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Little help needed.
I need to have valve guides replaced in a 850 head.
I will replace all of them need to know witch type steel or brass.
And can I fit all the same though out the head.I will be changing all the valves as well.i will be replacing all the springs swell.also can I use the later type oil seals .as the ring type had all broken when the head was taken apart.
Thanks a buy info would be great

The originals were cast iron guides and these are quite good. You can fit the Bronze Guides, I've found these last better, not to say that the Iron Guides wear badly, especially on motors with stock cam profiles. If fitting the Bronze Guides, be sure to ream them after fitting, as they close up a little and can grab the valve stem.

After fitting the guides, you'll need to re-cut the valve seats, as they is no guarantee that the new guides will be on the same centre as what was in there, also, there's a good chance the seat will need dressing in any event.

You'll need to have the iron ones reamed as well.
The valve seats will in 90% if the time need recutting, so prepare yourself for that.

If a road engine with road specs I'd fit iron guides.

I agree, stick with standard Iron valve guides, the bronze ones are only really for high performance applications, and the quality of after market ones is "variable". The best bet is simply to take your head to an engine reconditioner & ask them to replace the guides & do any other work necessary. They will clean the head, fit & ream the new guides & re cut the valve seats. If it hasn't already been done, this would be a good point to get "unleaded" valve seats fitted in the head to allow you to run on unleaded petrol.

M