tcchin
Zone Head
Posts: 867
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posted February 07, 2007 12:15 PM
Muzzy 1375, Web 227/549 p-to-v?
Does anyone have experience with the Muzzy 1375 kit (JE pistons) and Web 227/549 cams wrt piston-to-valve clearance? I found that the intake side had tons of clearance regardless of LC (.055"+), whereas the exhaust side required that I use a 110 LC in order to achieve .060" p-to-v. That seems a little odd, almost like the exhaust valve pockets were machined too shallow. If I'd used the Web spec of 104 EX LC without checking, I would have been running .030" p-to-v!
Squish was set conservatively at .036", stock valves, etc.
I did manage to fabricate an effective lever-type tappet depressor to do iterative p-to-v measurements without removing the head or gnarling-up the tappets with a screwdriver blade...
  
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THE ICE MAN
Expert Class
Posts: 195
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posted February 07, 2007 12:40 PM
quote:
Does anyone have experience with the Muzzy 1375 kit (JE pistons) and Web 227/549 cams wrt piston-to-valve clearance? I found that the intake side had tons of clearance regardless of LC (.055"+), whereas the exhaust side required that I use a 110 LC in order to achieve .060" p-to-v. That seems a little odd, almost like the exhaust valve pockets were machined too shallow. If I'd used the Web spec of 104 EX LC without checking, I would have been running .030" p-to-v!
Squish was set conservatively at .036", stock valves, etc.
I did manage to fabricate an effective lever-type tappet depressor to do iterative p-to-v measurements without removing the head or gnarling-up the tappets with a screwdriver blade...
I would not say conservatively, not at .036"
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Megabyte
Pro
Posts: 1047
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posted February 07, 2007 12:55 PM
I'm curious, why did you go with the Web Cams?
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We First make our habits and then our habits make us.
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tcchin
Zone Head
Posts: 867
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posted February 07, 2007 01:27 PM
Ice Man,
Are you saying that these motors need more than .036" squish?? That's already a huge number. I'm sure this is redundant, but please note that this figure is piston-to-head clearance, not piston-to-valve.
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Y2KZX12R
Needs a job
CompetitionCNC.com
Posts: 3762
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posted February 07, 2007 02:26 PM
Whats the lift on those cams?
For squish .036" is fine. I've run large displacement big block chevys closer than that.
I've run as tight as .028" on my 1375 zx12. Stock my bike had .022" intake valve to piston clearance. The cam was advanced 1.5 degrees.
Squish is very important for making power. It builds cylinder pressure very fast by accelerating the burn.
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Y2KZX12R
CompetitionCNC.com
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tcchin
Zone Head
Posts: 867
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posted February 07, 2007 02:52 PM
.383"/.369" advertised lift.
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entropy
Moderator
Posts: 8671
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posted February 08, 2007 01:52 AM
quote:
Does anyone have experience with the Muzzy 1375 kit (JE pistons) and Web 227/549 cams wrt piston-to-valve clearance?..
I have experience with 227, not the 549
quench = .037-.038" (depending on which cyl)
Intake: (cam LC at 104)
radial clearance = .046-.048 at the tightest spot
axial__________= .063-.065 where pocket breaks over to dome
axial__________= .072-.075 deep in the pocket
I backed off the LC to 108 for final build.
Chin,
i would like to see a pic of your valve tool. The clay method is tedious, limited, and hard to measure.
Better yet, could you please just make one and send it to me? please??? 
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entropy
Moderator
Posts: 8671
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posted February 08, 2007 02:13 AM
BTW:
for everybody running tight squish, Y2K and others have repeatedly said this, but i will repeat it.
I paid $8000 for my lesson...
Make double-damn sure yr motor is fully heat soaked before putting the screws to yr bad ass motor.
Not just seeing the temp gage at 9pm, but having the block, pistons, etc, etc at stable operating temp
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tcchin
Zone Head
Posts: 867
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posted February 08, 2007 12:08 PM
Aha - I was afraid that my mention of my precious valve tool went without notice! I'll contact you offline regarding prints, etc.
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supra5677
Pro
Posts: 1279
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posted February 08, 2007 12:40 PM
I just ordered a .383 lift 253 duration at .050 cam from webcam.. Intake cam..
they recommend 103 lobe center on the intake...Im going to run 105 to compensate for thin head gasket
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tcchin
Zone Head
Posts: 867
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posted February 08, 2007 12:50 PM
...So you're using the stock exhaust cam, or have you moved your intake cam over to the exhaust side? APE sells a spring/shim kit for that cam that Web highly recommends.
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supra5677
Pro
Posts: 1279
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posted February 08, 2007 01:34 PM
im using the stock exhaust cam.. which i think is fine.. I have an extended rev limiter also to get the most out of the cam... stock exhaust cam is .342 lift with 238 degrees of duration at .050..
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