Going with the 12610046 head gaskets - pushrod length change?

[TomPierce]

I had PatG spec me a custom cam and he specified a 7.425" pushrod (13115R EPS lobe intake and 13117R EPS lobe exhaust). When I was working out the parts order with Greg, he suggested everyone was using the 12610046 head gasket which I agreed to.

What with some of the recent posts I have read concerning engine builds, I am wondering if I need different pushrods due to the head gasket change. If I am correct, the stock gasket is .055 and the new gasket is .040 (is this correct?).

I will buy a pushrod tool to check the length, but I'm the kinda guy who likes to have all the parts in hand before starting a project. Given what you know, what length pushrod should I need?

(This is not the first engine I've been inside, but it is the first of these new-fangled zero-lash (or whatever its called) engines I've worked on).

Thanks!

[hartigan85]

The only smaller pushrod size you will find is a 7.400 which is too short and can cause extra valvetrain noise. either way its up too you. Have a pushrod that .010 too short or a pushrod thats .015 too long. IMHO I don't think you are going to see or notice any difference either way. Maybe one of the engine experts on this forum can give you a little more insight on this.

[Greg@PacePerformance]

Tom,
My book lists both the 12589227 (LS2/L76) and the 12610046 (LS3/L92) gasket at .051" thick
That is from the 2011 GMPP book.

Looking in the 2009 parts catalog GM list the L76 and LS3 as using the same head gaskets.

[TomPierce]

Great! Thanks Greg! Now I don't have to worry about it!

[-Ray-]

My push rods are 7.367" I have a set of custom heads though.
'

[morpheousssv]

I use 7.425 with Higgins heads and comp thumpr. 7.400 was too noisy.

[Greg@PacePerformance]

I'm using a set of these (http://forum.grrrr8.net/showthread.php?t=22919) - 7.450" I prefered them a little more snug.

[Matt@Texas-Speed]

My push rods are 7.367" I have a set of custom heads though.
'

Is that a tip-to-tip measurement or gauge length? The reason I ask is the stock pushrods when measured are about 7.400" TtoT, but gauge length which accounts for the size of the ball end is about 7.38x". Same for aftermarket 5/16" pushrods that are typically run on stock GM casting heads, they are ordered as 7.400" gauge length, but measure 7.417" or so TtoT. On the 5/16" pushrods we sell (as well as Comp and most others) it is a 0.017" difference, typically :)

[-Ray-]

Is that a tip-to-tip measurement or gauge length? The reason I ask is the stock pushrods when measured are about 7.400" TtoT, but gauge length which accounts for the size of the ball end is about 7.38x". Same for aftermarket 5/16" pushrods that are typically run on stock GM casting heads, they are ordered as 7.400" gauge length, but measure 7.417" or so TtoT. On the 5/16" pushrods we sell (as well as Comp and most others) it is a 0.017" difference, typically :)

The length is laser etched on the push rod. it's a comp cam push rod.

[Matt@Texas-Speed]

The length is laser etched on the push rod. it's a comp cam push rod.

I haven't checked a Comp in a while, but it'd be interesting to measure tip to tip and see what they are advertising :)

[-Ray-]

I haven't checked a Comp in a while, but it'd be interesting to measure tip to tip and see what they are advertising :)

When I do the trunions this Winter, I'll let you know.

[Crazy Paul]

12610046 head gasket.
I am wondering if I need different pushrods due to the head gasket change.
If I am correct, the stock gasket is .055 and the new gasket is .040 (is this correct?).

Download the 2011 GMPP Catalog
LS Parts are Pages 186 to 225.
Page 204 tells you head gasket thickness.
http://www.grrrr8.net/crazypaul/GMPP_Catalog_2011.pdf