12-02-2019, 11:23 PM | #1 |
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Valve Grinding
Hi All,
I have been grinding some Model A valves with my valve grinder and am finding by the time I am able to get a clean face there is not a lot of margin left. These are stainless valves with 70k+ miles on the motor but valves have not been ground before. Never had this concern before with flatheads and SBC's, newer motors etc. Anyone else experienced this? Thanks, Steve |
12-03-2019, 12:46 AM | #2 |
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Re: Valve Grinding
Don't know what your expecting, but with 70,000 miles, I would not grind them I would trash them. Valves are not that expensive. If you run a thin lipped valve, it is more likely to burn in the future. Also stem wear is likely. I wouldn't bother with them. JMO
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12-03-2019, 12:47 AM | #3 |
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Re: Valve Grinding
I don't know the specs on a model a, but I've found that a 1/32" margin on most old cars is enough.
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12-03-2019, 08:56 AM | #4 |
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Re: Valve Grinding
Specs for a margin can be tough to define. Valves come in all sizes. But a good rule of thumb, if it ends up being 50% of that on a new valve then I trash it.
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12-03-2019, 12:30 PM | #5 |
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Re: Valve Grinding
Are they original Ford stainless valves?---- they have a pretty thin margin to begin with
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12-03-2019, 10:00 PM | #6 |
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Re: Valve Grinding
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I have done a lot of motors over the past 50+ years, never had to go that far into the face to clean it up. |
12-04-2019, 12:43 AM | #7 |
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Re: Valve Grinding
Depending on where your seat is you can also turn them to 90 degrees in you valve Facer and gain some margin. Just saying.
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12-04-2019, 07:54 AM | #8 | |
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Re: Valve Grinding
Quote:
Thats a good point. If the seat contact can be moved toward the stem you could maybe grind some more margin. I happen to like the contact area near the stem. |
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