TR cams and pushrod length.
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From: Central, MA
TR cams and pushrod length. I'm getting a ton of KR at tip in after my cam install, and I'm trying go through everything to make sure the whole setup is 'sane'. I have a lot of 'sewing machine' valvetrain noise, but I think it's normal.
What are you guys with TR cams with unmilled heads, running for pushrod lenght?
I'm using 7.4" pushrods. TR uses 7.4's in their cam kits, so I never gave it a second though until now.
At first I thought 7.4" was the stock length. Then I heard about the 7.35's.
Are TR cams on a -.030" base circle?
What's the real story here?
What are you guys with TR cams with unmilled heads, running for pushrod lenght?
I'm using 7.4" pushrods. TR uses 7.4's in their cam kits, so I never gave it a second though until now.
At first I thought 7.4" was the stock length. Then I heard about the 7.35's.
Are TR cams on a -.030" base circle?
What's the real story here?
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From: Central, MA
Excellent. I figured the PR's were fine.
Do you get much valvetrain noise?
I ran the 918's via the stock cam for a few days, and they were as quiet as stock. I heard someone say in an old post that it might be the higher-rate springs, but I have to say it's not them.
Do you get much valvetrain noise?
I ran the 918's via the stock cam for a few days, and they were as quiet as stock. I heard someone say in an old post that it might be the higher-rate springs, but I have to say it's not them.
Originally Posted by 2xLS1
I'm using T/R 7.4s with my TR220 114 and they are working fine.
FYI 7.4 is longer than stock ok. Reason being most aftermarket cams have a smaller base circle than the stock cams. Basically the smallest part on lobes on the cam are smaller than stock cams in the same spot.
I too thought 7.4" was stock length. After all that is what they are advertised as. Then I looked up the part number for a stock LS1 pushrod and found the stock length. It was 7.318". I know there is great variance in pushrod length depending on endcap size, style, and manufacturer measurement standards. It cause my eybrows to shoot up, because I just replaced my stock pushrods with TR 7.4's. I have had them in the car for about 1000 miles now and have been to the track a few times and nailed it a few more. Zero problems, and valvetrain is quiet as stock.
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After listening closely, I am getting a bit of a 'tap tap tap' from the valvetrain.
Anyone have any insight or direction in where I should head?
Retorque the rockers?
Throw a couple of stock pushrods in to see how they fit with the rockers torqued down?
Anyone have any insight or direction in where I should head?
Retorque the rockers?
Throw a couple of stock pushrods in to see how they fit with the rockers torqued down?
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I'm really second guessing myself now. 
The chances are "slim to none" that I somehow put something together half-a$$ed, right?
I swapped the springs Friday night. Slapped it back together at 2am, and the thing was running perfect. I tore it all down again on Sunday for the cam swap.
Is it possible to not get a pushrod fully seated in the rocker? I doubt I'd miss something like that on a nice bright Sunday afternoon.
The chances are "slim to none" that I somehow put something together half-a$$ed, right?
I swapped the springs Friday night. Slapped it back together at 2am, and the thing was running perfect. I tore it all down again on Sunday for the cam swap.
Is it possible to not get a pushrod fully seated in the rocker? I doubt I'd miss something like that on a nice bright Sunday afternoon.
Marc-I'm sure its fine. If you didnt seat a PR right, you'd know it by now. The tap tap is the valves slamming shut. My car's valvetrain is loud at 2000rpm...as is every other aftermarket cammed LS1.
Thanks for the reassurance... that'll save me an hour tonight.