VVT + Supertech pistons = interference engine
#22
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Mostly trying to get an idea for what the limitation is as far as valve lift goes.
Jason, do you have a '99 head laying around that you can take the same measurement on? If the '99 head is still non-interference with 8.6:1 Weiscos then IMO it's safe to assume that full advance on the VVT won't cause an issue (if more cam retard = tighter clearances as neo said).
Jason, do you have a '99 head laying around that you can take the same measurement on? If the '99 head is still non-interference with 8.6:1 Weiscos then IMO it's safe to assume that full advance on the VVT won't cause an issue (if more cam retard = tighter clearances as neo said).
#25
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You're completely right though, if I were going to be making larger cams for a VVT engine I'd be checking valve to piston and valve to valve clearance carefully.
#34
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I know... but you can grind a flycutter in a few minutes and not have to order it. You're right though, it is sort of a preference thing. If I was going to be doing a ton of valve pocket cutting of the same pocket size I'd get the mill. For a once in a while thing or if you're doing a bunch of different pocket sizes I'd use the flycutter.
#36
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Sigh, guess I'll want to be checking my wisecos, they aren't FM's... Is there an easy way to tell FM's part number from the "regular" miata wisecos?
The VVT cam does have more lift. I have both heads, but not the pistons handy. I would love to go to a higher lift cam at some point.... Would like to think I'm not going to be in any trouble here. Certainly more pocketing and less compression would work well.
Jason - your measurements are vertical, or in the slope of the valve?
The VVT cam does have more lift. I have both heads, but not the pistons handy. I would love to go to a higher lift cam at some point.... Would like to think I'm not going to be in any trouble here. Certainly more pocketing and less compression would work well.
Jason - your measurements are vertical, or in the slope of the valve?
#38
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Jason,
I just ordered a set of these last week and from what I have understood from this thread is that as long as I change my timing belt religiously and it does not break I should be fine right?
I just ordered a set of these last week and from what I have understood from this thread is that as long as I change my timing belt religiously and it does not break I should be fine right?