Valve guide boring

Hi, I've just got my new Exhaust valves for my '96 Dart heads (Hemi) and apparently Manley don't do .341 stems anymore so i've now got .375 and I'm going to machine out the guides , My questions are 1) Will i have to make new bronze inserts as I'm sure there won't be any left by the time they are bored out and 2) how much clearance do the valve stems require ?
Thanks for any help
Wayne

 

Right , as i had no replys I've attacked the guides, the bronze inserts came out easily and the guides measure to 3/8" after a little clean up with a reamer, now the valves which are also sold as 3/8"s, measure at 3 thou under 3/8" (.372") so my new question is
Is 3 thou too much clearance or about right , the valves waggle a little bit in the guides and i know they will expand and tollerances will tighten up when it's running, just want to get it right while it's in bits
Thanks for any help
Wayne

 

When my heads were done the first time....i had .001 guide clearance. On the first full pull, it grabbed an exhaust valve. now they are all .0027 or so, just she of .003". No more problems. No smoke on startup, and it runs great

 

Dragsterbus, K-line makes liners for .375 guides. Contact your local machine shop and have them install the liners. I would recommend .0015-.002 on the intake and .0025-.003 on the exhaust. The liners cost about 2.00 apiece and about 6.00 to install and size where i am at. I would not recomened running a steel or ti valve against a steel guide. K-liners are made of bronze or combo of bronze alloys that make it hard to stick a valve.

 

Thanks for the replies guys, my heads are at the machine shop now and we took the old K-line liners out and they are going to bore the guides out and fit new L-lines, Great minds etc etc ha ha,
Thanks again!
Wayne

 

#1 valve carries the clearance not the guide
#2manley still makes 11/32 valves
#3 you can put an 11/32 liner in a 3/8 hole to shrink it down

 

1# I realise that now
2# They told me they didn't
3# The valves are in with new K lines etc and with the seats re cut
Thanks for your input