6 posts • Page 1 of 1
Was doing a valve job on a 51 Chief motor yesterday. I always check valve face to seat contact with a little fine lapping compound and found that I wasn't getting the full width of the seat. Turns out the valve surface was ground at 33 degrees on the new nitrided valves I got from Eastern. Easy fix but I just thought I would mention it in case somebody out there was in the middle of a valve job and missed it. Not much heat transfer with a .010 wide valve to seat contact.
Tom, What are you using for seat and valve angle? I was going to recut the valve faces to 31 degrees to match my neway cutter, but opted to redress my grinding stone to just over 33 degrees the valve was. On all the Chief jobs I've done, there has been some room to position the contact area on the valve face on the intake side, but the exhaust always end up on the outside edge of the face. The exhaust opening doesn't have any material to work with inside. I suppose there isn't enough spring pressure to cause any trouble with a fresh valve, but it would be nice if the ex valves were 1/16 OS. Danny, I really like the slippery nitrided valves and they are only a little more money than the Chevy valves. I bought a couple of sticks of G2 cast iron rod with a big enough diameter to make Chief guides (what a waste of expensive material, just to accomodate the big shoulder) and have been tightening up the clearances to help with longevity.
The Chevy valves have 2 keeper grooves. The top groove is in the same place as the Chief and that is the ONE you use. The stems are I believe .002 LARGER than Indian so you can sometimes save a marginal guide. The machining part is that the head is about .125, I believe, larger so you just have to turn it to size, also able to use a deeper seat by leaving it a little oversize, and then put it to 35* before finish grinding. I am citing these specs from memory as I am not in the garage. Kyle we just got tired of paying the Indian suppliers $25 or more a valve! P.S. on SOME Scouts (101's for sure) you can get Diesel Truck shoulderless guides with the proper I.D. for about $3 and just modify them for use.
6 posts • Page 1 of 1
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