 Deck Height, using shims UNDER the cylinder |
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| IHHRA |
 Dec 11 2011, 09:14 PM
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Newbie  Group: Members Posts: 2 Joined: 11-December 11 From: Western NC Member No.: 13,888 Region Association: None  |
When calculating compression ratio, is it a no-no to use more than one shim under the cylinder to get the desired DH?
Thanks, Bill |
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| '73-914kid |
Dec 13 2011, 12:32 PM
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Senior Member Group: Members Posts: 1,473 Joined: 1-November 08 From: Vista, CA Member No.: 9,714 Region Association: Southern California  |
On stroked motors, or motors that are not your "typical" combination, the only way to avoid shims is to either mill down the top of the piston, or just run astronomical compression ratio. Without shimming my cylinders, I would have had a compression ratio near 12:1. FAT performance can cut shims to any thickness you want IIRC.
Just make sure when you do get shims, or decide to stack the shims, deburr them like Sean said. Otherwise when you put things together, take them apart repeatedly during mock-up, you deck height will change throughout as things settle in. I don't have any experience in shim stacking to recomend or discern it though. I was lucky enough to find a little VW shop that had EMPI produced shims from the late 80's. They are out there, you just might have to call around. What size shim are you thinking you will need? |
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Posts in this topic
IHHRA Deck Height Dec 11 2011, 09:14 PM
Mark Henry Three shims max, but I would get shims made by RIM... Dec 11 2011, 09:49 PM
IHHRA
Three shims max, but I would get shims made by RI... Dec 12 2011, 08:54 PM sean_v8_914 burnish the faces and de-burr teh edges. Dec 12 2011, 08:51 AM 76-914
Three shims max, but I would get shims made by RI... Dec 12 2011, 10:39 PM Mark Henry
Three shims max, but I would get shims made by R... Dec 12 2011, 10:54 PM sww914 I can't recommend it, but I ran 5 shims in my ... Dec 13 2011, 11:31 AM stugray How about NO shims?
Any advice on that one?
Stu Dec 13 2011, 12:07 PM wndsrfr
How about NO shims?
Any advice on that one?
Stu... Dec 13 2011, 12:39 PM bobhasissues Type IV shim sets available at DRD Racing approx ... Dec 13 2011, 01:07 PM |
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