Push Rods
#1
Senior Member
MASTER BUILDER
Thread Starter
Join Date: Aug 2007
Location: Iowa - USA
Posts: 218
Push Rods
I'm replacing the cam in my bbc (468 -12.5 compression) with a comp cams solid roller, springs, rockers, etc. I need pushrods. I don't know what to order. The heads are ported GM iron heads. Any help would be appreciated.
#2
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RACING JUNKIE
Join Date: Sep 2007
Posts: 4,137
#3
Senior Member
MASTER BUILDER
Join Date: Jan 2008
Posts: 146
Re: Push Rods
Originally Posted by jreiley
I'm replacing the cam in my bbc (468 -12.5 compression) with a comp cams solid roller, springs, rockers, etc. I need pushrods. I don't know what to order. The heads are ported GM iron heads. Any help would be appreciated.
comp cams parts, and your not using there push rods???
whats going on here?
i would stay with comp products ,its a safe bet
#7
A lot depends on the RPM you plan to run. You need an adjustable pushrod to figure out what length you need, this is one of the last things you do after the engine is assembled. Variations in cams, lifters, valve lengths, deck height, how much the heads are cut, gasket thickness, and the type of rockers all make each engine unique. You need a light weight spring on the intake and exhaust of one port to check, you want the line between the pivot centerline and the roller tip centerline perpendicular to the valve stem at mid lift. This will create the smallest arc across the tip of the valve which loads the stem the least. If you run standard rockers and guide plates you are limited to the guide plates as far as diameter. .080 is OK at 7000 or under, thicker is better at controlling harmonics and a good idea if you run it higher. If you run shaft rockers, as Todd suggested run the largest that will fit. Manton, Trend, and Smith Brothers all make quality pushrods, I run 7/16 .140 wall Manton in my SB2. I had quick service from Manton, ordered on Thursday and had them Monday.