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DISCUSSION => Swaps, Turbos, Buildups => Topic started by: thetomc on October 26, 2009, 12:05:18 PM

Title: Ring Gaps for M42 Rebuild?
Post by: thetomc on October 26, 2009, 12:05:18 PM

Hi Guys,
As it says in the title i'm trying to find the correct ring gaps for an M42 engine rebuild.
Any help will be much appreciated.
Thanks,
Tom

[I'll elaborate on the details of the build shortly :)]

Title: Ring Gaps for M42 Rebuild?
Post by: 1991 E30 M42 on October 26, 2009, 03:15:45 PM

if you are wondering about piston gap, it varies depending on the material and what your are going to use the engine for

Title: Ring Gaps for M42 Rebuild?
Post by: dsm2002 on October 26, 2009, 06:59:20 PM

1991 E30 M42 is correct. It does depend on the rings and what your are going to use the engine for. Usually you set the gap based on specs which should be supplied with the rings. Otherwise here is the stock gaps for reference.

(http://i16.photobucket.com/albums/b15/dsm2002/M42rings.jpg)

Title: Ring Gaps for M42 Rebuild?
Post by: thetomc on October 27, 2009, 01:40:14 AM

Thanks guys.
I wasn't aware that the ring gaps would be supplied with the rings.

As for piston running clearances (piston to bore); i will be checking that the parts i'm using aren't far from stock data which i'm sure i found somewhere yesterday.

dsm2002 - where did you get the data from. I hunted around for data like that most of yesterday afternoon with no luck. I mainly found lots and lots of dead links to Bentley manuals. The only section i want is the M42 data.

Engine is going to be used for track and sprint and a thrash around the countryside every so often.