Pelican Parts Forums

Pelican Parts Forums (http://forums.pelicanparts.com/)
-   911 Engine Rebuilding Forum (http://forums.pelicanparts.com/911-engine-rebuilding-forum/)
-   -   What's acceptable piston to valve clearance? (http://forums.pelicanparts.com/911-engine-rebuilding-forum/1021755-whats-acceptable-piston-valve-clearance.html)

JoeMag 02-22-2019 01:43 PM
What's acceptable piston to valve clearance?
 
race motor 3.8 with rsr cams, mahle rsr pistons, carillo rods, ebs race springs set at 88lbs seat pressure, red line 7.5k.

I've seen 1mm is fine, but have seen higher numbers too, up to 1.8mm.

thoughts?

MBruns 02-22-2019 03:20 PM
V to P
 
Minimum of 1mm on intake at the closest point and 2mm on the exhaust side closest point will be providing springs are adequate, I have seen closer than that without contact but that’s my minimum
Mike Bruns

JoeMag 02-22-2019 03:23 PM
Thanks mike... ebs springs were the highest spring rate I could fine at 375 lbs/in.

JoeMag 02-25-2019 08:29 AM
...guess i'm good. came up with 2.5mm intake and 2.7mm on exhaust. basically got to minimum 10 degrees before tdc overlap on exh and 10 degrees after on intake.

MBruns 02-25-2019 08:48 AM
That’s perfect


All times are GMT -8. The time now is 09:20 PM.

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.