Good idea....since I already know from experience .027 is fine.
So your "no personal experience" .060" "answer" that you seen somewhere is of no use to me.
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Good idea....since I already know from experience .027 is fine.
Did some calcs using your numbers. When I use .004" guide clearance on both valves I get the numbers you measured. The lift at overlap would probably be closer to .250", that reduces side-side movement by .001 combined from your measured so gap between valves when pushing together would be .0163" at .250 lift. With guide clearance of .002 on both valves keeps the valves apart more to .0217" at .250 liftgmrocket wrote: ↑Tue Jan 16, 2018 3:18 pm i checked those measurements before, they are...
.027" between valves when seated with a little slop in the guide..about .001 more than it should be
guide to seat is 1.425", its not a tall head so that helps
11/32 stem
2.00" guide length
dont know cam yet so did a check at .500" , spread distance increased to .0385" and pinched together it was .0155"
these were run like this and no problems. im moving the guides in the heads they are going in and would like to get them as close as possible so everything fits better. reducing it to .020" is what i would like
What was the point in even posting that? Are you implying eveyone else is wrong?
bigjoe1 wrote:By the way, I had a long talk with Harold(Brookshire) last year at the PRI show. We met at the airport and he told me everything he knew about everything.It was a nice visit. JOE SHERMAN RACING
Earlier you said with Ti valves I could probably get away with .020 or even less...what changed?KnightEngines wrote: ↑Thu Jan 18, 2018 6:51 am .020 is not enough, youd be suprised how much valves whip around at higher rpm.
I run a lot of stuff at .028 to .035 without problems, but at .020 they've touched & knocked around the margins.
Makes sense....thanksRick360 wrote: ↑Thu Jan 18, 2018 1:01 amDid some calcs using your numbers. When I use .004" guide clearance on both valves I get the numbers you measured. The lift at overlap would probably be closer to .250", that reduces side-side movement by .001 combined from your measured so gap between valves when pushing together would be .0163" at .250 lift. With guide clearance of .002 on both valves keeps the valves apart more to .0217" at .250 liftgmrocket wrote: ↑Tue Jan 16, 2018 3:18 pm i checked those measurements before, they are...
.027" between valves when seated with a little slop in the guide..about .001 more than it should be
guide to seat is 1.425", its not a tall head so that helps
11/32 stem
2.00" guide length
dont know cam yet so did a check at .500" , spread distance increased to .0385" and pinched together it was .0155"
these were run like this and no problems. im moving the guides in the heads they are going in and would like to get them as close as possible so everything fits better. reducing it to .020" is what i would like
IMO with new guides and .020 valve gap when on seat should be enough unless your valves are really bouncing around in there or when the guides get worn.
Rick
I also said near perfect valve train control - the sort of near perfection that requires spintron time & $$$$ parts.Earlier you said with Ti valves I could probably get away with .020 or even less...what changed?
I don't think a Ti valve is a normal part...it'll have del west valves, Ti retainers, Ti locks, PAC springs, T&D shaft rockers. Quality push rods, Lift in the .800" to .850" range and a lobe that won't have really aggressive ramps.. but big .050" numbers in the 285+ range.KnightEngines wrote: ↑Thu Jan 18, 2018 5:00 pmI also said near perfect valve train control - the sort of near perfection that requires spintron time & $$$$ parts.Earlier you said with Ti valves I could probably get away with .020 or even less...what changed?
Using 'normal' parts & educated guesses as to valve train components (like we all do for the vast bulk of engines) I wouldn't go much under .030", certainly not under .025"
Ya, I wish someone else would have done the dirty work, I hate experimenting with $2000 valves .KnightEngines wrote: ↑Thu Jan 18, 2018 6:15 pm Entirely your call, but I'd keep it above .025" - you may well be fine, but I'm not gonna be the guy that said you will have no problems & then get called bad words if it doesn't work out!
If you do run it at .020" then pull the heads after a little run time & check that all is good.