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> Setting up DH and CR, Can someone check my math?
swood
post Sep 18 2003, 07:35 PM
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I mocked up the p&c's on the shortblock here's what Ive got:

Bore - 96mm
Stroke - 66
Cylinder Head vol - 53cc
Deck height (no barrel shim) - .047" (all the way around)
CR calcs out to 8.75:1
If I add a .010" shim it will go to DH-.058"
CR calcs out to 8.53:1

Opinions? I'm thinking that an 8.5:1 is suitable for this app. (1911cc).

Oh, and I haven't lapped the heads yet now that I'm thinking about it. Should that be done prior to setting up the DH & CR?

Also, I forgot to threadlock the flywheel bolts. Is this really necessary? If so, I take all that off again...



Thanks guys, I'm getting there.
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swood
post Sep 18 2003, 10:27 PM
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Oh yeah, and my cam is a Web #73.
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Charles Deutsch
post Sep 18 2003, 10:27 PM
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I get the same numbers but for the second c/r calculation I used DH = (0.047 + 0.010) = 0.057" not 0.058" .
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Brad Roberts
post Sep 18 2003, 10:30 PM
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Your good with the compression. Dont worry about the loctite on the threads unless you used a old lock plate.

And.. lapping the heads wont change the compression. Your not removing material.. just scuffing it up.


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swood
post Sep 18 2003, 11:30 PM
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Do you mean I'm good with compression without the shim?

Do you mean the plate that goes under the bolts? I did put in on there. I haven't heard that it's not necessary.
Thanks,
s
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Brad Roberts
post Sep 18 2003, 11:32 PM
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I would run the 8.75 without the shim.

If you reused a old lockplate (the one that goes under the bolts) then loctite them. The book calls for a new one every time you remove the flywheel.



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swood
post Sep 18 2003, 11:34 PM
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Since I just put my last spare one on, should I just pull it off and loctite the bolts with out it?
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Brad Roberts
post Sep 18 2003, 11:37 PM
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You should always run the plate.. the loctite is just a extra added layer of protection.



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swood
post Sep 18 2003, 11:38 PM
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Roger. Over and out.

and thanks.
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Brad Roberts
post Sep 18 2003, 11:41 PM
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Where is LBC ??


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swood
post Sep 18 2003, 11:43 PM
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Funny. I'm asked that often. It's just Long Beach. But it's slang for Long Beach City or Crips, depending upon which side of the tracks your (I'm) on. But I usually just refer to it affectionatly as Snooptown, since he's from around the corner. (IMG:style_emoticons/default/ph34r.gif)
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Brad Roberts
post Sep 18 2003, 11:45 PM
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I thought it was Long Beach.. but didnt know what the C stood for. Gotcha. How far from Wesct Coast Choppers are you ??


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swood
post Sep 18 2003, 11:49 PM
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not far enough from that prick. i pass by there on occasion as one of my shortcuts home from the office. He's about 2 miles from my house. This is really a hot rod town. My block is like a nightly trip to the track. Every other neighbor does at least a few hot runs a week. Kinda cool!
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swood
post Sep 18 2003, 11:51 PM
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How far are you from San Bruno? We're working on the mall right next to the airport and I go up there every now and then. It'd be cool to meet you mid-left coasters sometime.
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Brad Roberts
post Sep 19 2003, 12:06 AM
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San Bruno is 50 minutes south of me (easy jaunt) let us know when you are in town.


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Brett W
post Sep 19 2003, 06:55 AM
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If you can have Rimco or your local machine shop take .005 off both ends of you cylinders to square them up bolt them on and run them. This should get your compression into the low 9s. The tighter you run the deck the better off you are. other wise I would run the set up without a shim. What cylinder wall clearence are you running?
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swood
post Sep 19 2003, 08:04 AM
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Not sure. I had trouble with that measurement. I'll try again. That's between the wall and the skirt right?
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