Tunion upgrade, Bronze or Needle?
Thread Starter
Joined: Nov 2011
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From: Sonoma Co. Ca.
Tunion upgrade, Bronze or Needle? I've read where many on this site swear by the stock rocker arms with a tunion upgrade is the way to go. I am currently using a good quality American made adjustable that are too big to fit under Holley valve covers with baffle removed so I use a spacer but the spacer doesn't seal very well and leaks oil, not a lot but just enough to be annoying . So, with stock rocker arm upgrade, what is the better way to go? Bronze or needle bearing? Oh Yeah, .625 lift, BTR platnum spring kit in use here. The heel of the current rockers are rubbing the inside of the v/c's and spacer putting aluminum into the oil.
Last edited by 64post; Apr 6, 2017 at 08:12 AM.
Only caution I would have is if your heads have bronze guides. If they do then the stock rockers will result in more guide wear. If they are GM heads with the powder metal guides you will be fine. I would likely go with the bronze bushing over the needles myself as well.
If somebody actually made a needle bearing kit that was of good quality and the trunion was machined correctly out of the correct material, that would be the way to go. Since none of that seems to be happening, go with the bushings and save yourself a lot of grief down the road.
TECH Senior Member
Joined: Jun 2016
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From: Central Cal.
The trunnion upgrade replaces the stock non-caged needle bearings(which COULD fall apart with potentially disastrous results) with either a better caged needle bearing or a bronze bushing, both of which come with a new trunnion.
The trunnions of the caged bearing conversions were found to be wearing prematurely due to poor metallurgy. The bronze bushing has found more favor as they prove more durable.
The trunnions of the caged bearing conversions were found to be wearing prematurely due to poor metallurgy. The bronze bushing has found more favor as they prove more durable.
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I noticed there wasn't many comments in this thread. https://ls1tech.com/forums/generatio...ing-noise.html
TECH Senior Member
Joined: Jun 2016
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From: Central Cal.
I noticed there wasn't many comments in this thread. https://ls1tech.com/forums/generatio...ing-noise.html
You cannot really determine that unless the bushing is worn a LOT. You would have to either measure the bushing and see if it is out of round, or you would feel the slop between the rocker arm and trunion. They will always look nice because as the bushing wears, you will see more engagement where it contacts the trunion.
I have the Straub Kit. Chris is super easy to work with and a great guy to talk to as well. Too many of the "Comp Trunions" showing wear for my liking is why I went the bronze route.
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If somebody actually made a needle bearing kit that was of good quality and the trunion was machined correctly out of the correct material, that would be the way to go. Since none of that seems to be happening, go with the bushings and save yourself a lot of grief down the road.
