80" Evo optimum squish clearance?

[Finn]

Right.

Evo is in for suspension work and after that we/they freshen top end a bit.

There is now Andrews EV13 in and it will stay. Apart from our cam&lifter change last year engine has never been open and compression ratio, heads etc. are in stock form.

If I recall correctly Andrews have informed that their compression ratio recommendation for EV13 is 9.25:1 (9.5:1 for EV27).

   1. Sorry for stupid question but that recommended CR is surely static and not corrected, right?

   2. Is there a recommended squish clearance for Evos or does it matter?

[Deye76]

Stock head gasket is .045 you can tighten the squish with MLS gaskets in .040 or .030.
My guess is Andrews referring to static. Big Boyz Calculator will help you.
http://bigboyzheadporting.com/EVOComp.htm

[Finn]

Thanks.

Need to make some calculations with said 9.25:1 in mind.

[MikeL]

I'm doing a top end on a 1993. when I pulled it a part i found a comp cams evl-2030 installed. I'm going to have to raise the compression somewhat to make this cam work. I left the pistons in the cylinders the money is not there for domed pistons. Getting the heads done gonna mill and maybe install intake valves that are flat and not dished hoping decreases some of the combustion chamber volume. I'm also going to set the squish at .020 meaning the piston will be .010 above deck. Using cometic MLS head gasket and cometic base gasket.
In addition to the evl-3020 I have ev-27, ev-3,S&S 502,and fireball 326. I have the tool to R&R evo cams off the gear I can also advance and retard the timing to the cam. Anybody have any experience with the cams I have listed?

[kd]

.020 is a pretty close quench dimension. Especially in a cold engine  with carbon buildup that is run too hard.  Have you used .020 before?

[JSD]

.030" unless race bike that get pulled down alot. Tap Tap