Pelican Parts Forums

Pelican Parts Forums (http://forums.pelicanparts.com/)
-   911 Engine Rebuilding Forum (http://forums.pelicanparts.com/911-engine-rebuilding-forum/)
-   -   Too short new Mahle 2.7 RS Cylinders, Anyone heard about these? (http://forums.pelicanparts.com/911-engine-rebuilding-forum/433255-too-short-new-mahle-2-7-rs-cylinders-anyone-heard-about-these.html)

whackit 09-30-2008 06:09 PM

Too short new Mahle 2.7 RS Cylinders, Anyone heard about these?
 
Hi all,

I have a new set of pistons and cylinders from Mahle, a 2.7RS euro set. My deck height required much more shimming than either me or my machinist (he is the best... guess who) thought was normal. It turns out that Mahle made a bunch of 2.7RS sets that had too short cylinders. Has anyone else heard about this? I'm just not too keen on running my new engine with a pile of shims under it.

Thanks.

Bobboloo 10-01-2008 08:11 AM

What's the height group marking? I can't imagine how Mahle could sell a cylinder that doesn't match it's height group marking.

How much deck height do you need to make up?

Lot of good machinists. My favorites in L.A. area are Walt and Ollies.

Steve@Rennsport 10-01-2008 08:48 AM

We haven't seen any issues with current 90mm RS P/C's, but that doesn't mean there isn't a problem out there. :)

I will mention that when the case gets decked (as it should) and if the case halves are machined and centerlines bored back to standard, the whole assembly gets slightly narrower and so sometimes thicker base gaskets are needed to hit the desired deck height figures.

Like Henry, I don't ever use more than two of these on each cylinder and I have sources for a range of sizes to set everything up properly.

Sounds like more investigation may be needed,.....:)

whackit 10-01-2008 09:30 AM

I have to make up 1.75mm which will require 3 shims which I am trying to avoid. It seems the short cyls was a rumor, I can't find a source for .75mm shims. I may tru to get away with 1.5mm which will put me right at 1mm but I had my heads cut so that worries me.

Bobboloo 10-01-2008 09:51 AM

Cutting the heads won't affect your deck height but it will affect valve clearance and CR.

cgarr 10-01-2008 09:59 AM

Were the case halves shaved for boring?

whackit 10-01-2008 10:12 AM

yes, shaved, bored, decked. done by walt.

Quote:

Cutting the heads won't affect your deck height but it will affect valve clearance and CR.
it's the valve clearance that worries me. I'll be running E cams. Not so worried about CR as it's the 8.5:1 set

304065 10-01-2008 12:02 PM

What is the measured cylinder height?

whackit 10-01-2008 12:26 PM

it's correct. I measured it against an old cylinder I had. 85.5mm

cgarr 10-01-2008 01:03 PM

Shaving the case is going to change your deck, how much did they take off the case?

Steve@Rennsport 10-01-2008 01:28 PM

Quote:

Originally Posted by whackit (Post 4212708)
yes, shaved, bored, decked. done by walt.

There you go,.... :) :) :)

Thats why you are having the difficulties.


All times are GMT -8. The time now is 07:37 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website


DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.