AirSpeed VW Community Forums

Technical => Engine Tech Forum => Topic started by: orangecrush on May 02, 2013, 03:57:12 PM

Title: Valve clearance with Chromoly Push Rods
Post by: orangecrush on May 02, 2013, 03:57:12 PM
What is the setting when running Chromoly push rods with 1.25 high ratio rockers?
The block is a EMPI H.D. engine case 94mm 10mm Case Studs
69mm 4140 Chromoly Counter-Weighted Crank 8 dowel
4140 Chromoly I-Beam Rods
5 1/2 LB Crankshaft Pulley
Lighten flywheel
Mahle 94mm forged pistons
Hi-Performance heads Single Spring 3 way valve cut, 35.5 exhaust 40mm intake
Engle W110 Cam with 30mm lightweight lifters
Stainless Steel Windage push rod Tubes
1.25 High-ratio Rockers with Chromoly Push Rods
High capacity oil pump
1.5 qt High Capacity Oil Sump
40 IDF Weber Carbs
Protronix Distributor with Flame Thrower Coil
The Crank,Rods, Pistons,Flwheel, Front pulley are all balanced

I have the valves set @.006

Thanks
Rob
Title: Re: Valve clearance with Chromoly Push Rods
Post by: owdlvr on May 02, 2013, 04:27:19 PM
Chromoly pushrods are usually set to "loose zero". You adjust them so that the rocker has no play, but you can still rotate the pushrod with your thumb and finger.

-Dave

Title: Re: Valve clearance with Chromoly Push Rods
Post by: orangecrush on May 02, 2013, 05:47:24 PM
Thanks Dave for the info...I've been on the Samba site where they were talking about valve clearances and they suggested the samething you said. I think to be on the safe side is that I'm going to set them @.002 . What do you think?


Rob

Title: Re: Valve clearance with Chromoly Push Rods
Post by: owdlvr on May 02, 2013, 06:38:33 PM
I'd go with whatever Darren Krewenchuk says (K-Roc)...but I was at his place last week and he confirmed loose-zero with chromo pushrods was the way to go for me.

-Dave
Title: Re: Valve clearance with Chromoly Push Rods
Post by: Randy on May 02, 2013, 07:10:39 PM
What did the engine builder set them at?
Title: Re: Valve clearance with Chromoly Push Rods
Post by: Geoff on May 04, 2013, 07:10:26 AM
Always set loose zero, the lash will open up as soon as the engine warms up. If you set them to anything other they will make noise when warm.
Title: Re: Valve clearance with Chromoly Push Rods
Post by: orangecrush on May 04, 2013, 11:38:24 AM
What did the engine builder set them at?

I think there were set @.004

Thanks everyone for all info  :great:


Rob