Push rod guide plates or not?
Thread Starter
Drifting
Joined: Dec 2012
Posts: 1,504
Likes: 73
From: Georgetown TX
Push rod guide plates or not?
1989 stock
I’m confused. I’ve read that L98 aluminum heads have hardened push rods and use guide plates, and I’ve read they don’t use guide plates. My heads do have guide plates, but was told they are there only because they were used at assembly Anyone really know the answer?
I’m confused. I’ve read that L98 aluminum heads have hardened push rods and use guide plates, and I’ve read they don’t use guide plates. My heads do have guide plates, but was told they are there only because they were used at assembly Anyone really know the answer?
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Siveck is right that the plate is only there for assy, and the tip or the rocker overlaps the valve stem tip, thereby aligning the rocker.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
They are, as you move up the RPM range. For an '89 TPI (the OP's car) it ain't gonna matter either way. Which ever is cheaper/easier is better than good enough.
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Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
Aligned
But
in my 57 chevy truck there lives an 89 corvette L98 with a 4+3.
i have been using comp cams roller tipped rockers with the factory guide plates for about 8 years.
recently i switched to Harlan Sharp 1.6 full roller rockers.
still no problems not using self aligned rockers.
do your own testing. Be a myth buster.
in my 57 chevy truck there lives an 89 corvette L98 with a 4+3.
i have been using comp cams roller tipped rockers with the factory guide plates for about 8 years.
recently i switched to Harlan Sharp 1.6 full roller rockers.
still no problems not using self aligned rockers.
do your own testing. Be a myth buster.
Racer
Joined: Feb 2005
Posts: 338
Likes: 49
From: Quincy,Illinois
Now running Manley hardened guide plates and pushrods.