Comp Cams Trunnion Upgrade Failure

[1sick_eg]

The good thing about the TFS heads is they do come with powdered metal guides. Whereas the PRC and MAST come with bronze. Just something else to think about when it comes to your rocker selection.

[Firefighter]

Originally Posted by 1sick_eg

I would imagine you could get the TFS 255 heads from Cam Motion as well. I wouldn't run them however. Not unless you plan on changing out the intake valve. They come Solid stainless from trickflow. Not much of an issue if you were going with a solid, but that's a lot of weight for those hydraulic lifters. I would go with the PRC heads, Mast if you have the cash, or if you're ok without the car for a couple of weeks, I would send the ls3 heads off to Frankenstein racing. It'll save you about $1000 if you're keeping the stock valves.

I've been thinking about all these things. LoL I want to get it right the first time. The way I figure is I have 5 or 6 months the get the cash together and do research.

I didn't know that Cammotion would go through the heads and match the manifold though. I'll have to call and ask.

Originally Posted by 1sick_eg

The good thing about the TFS heads is they do come with powdered metal guides. Whereas the PRC and MAST come with bronze. Just something else to think about when it comes to your rocker selection.

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[1sick_eg]

Originally Posted by Firefighter

I've been thinking about all these things. LoL I want to get it right the first time. The way I figure is I have 5 or 6 months the get the cash together and do research.

I didn't know that Cammotion would go through the heads and match the manifold though. I'll have to call and ask.









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I missed the part about having your intake port matched. They may be able to get someone to do it for you, but they don't do that sort of work in house. Other than that, they can get you setup with everything.

[Firefighter]

Originally Posted by 1sick_eg

I missed the part about having your intake port matched. They may be able to get someone to do it for you, but they don't do that sort of work in house. Other than that, they can get you setup with everything.

Well I know PRC can do all that work and then have the cam/valvetrain set up by Cammotion.

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[CWI]

The rocker that failed was #1 intake and after pulling all the left bank rockers tonight, #5 intake has play in it so it was only a matter of time for it. Only have a little time each night so will check out the other side after I get this side back together. When the OEM rocker bearings failed two years ago it was #4 intake and #5 intake.

This has me wondering, is there some kind of vibration set up by the lighter sodium filled intake valves that is helping the bearings wear quicker? I just find it odd that the problem only seems to be on intakes.

[1sick_eg]

Nothing more than 40-50k on a big cam in my opinion. I'd rather have the hollow stems than a heavy stainless. You'd likely lose a lifter far sooner than that.

I'd say you did pretty well for that cam. I don't think LG releases their specs, but I imagine they gave you a cam card. Do you know the exact specs?

[CWI]

Originally Posted by 1sick_eg

Nothing more than 40-50k on a big cam in my opinion. I'd rather have the hollow stems than a heavy stainless. You'd likely lose a lifter far sooner than that.

I'd say you did pretty well for that cam. I don't think LG releases their specs, but I imagine they gave you a cam card. Do you know the exact specs?

The cam and lifters are fine. Only 15K on them. I should have changed trunions when I went bigger on the cam. I installed the new bearings on one side today and changed the oil to get some of the metal out. Will change it a couple more times with cheaper oil to get the most out as possible. Purrs like a tiger again. Valve train quieted down a lot.

Ordered some LS30 5W30 to try it out in comparison to Redline. Same price with free shipping on Amazon Prime. Not the first time it's had metal in the pan. It will be fine till I stroke it later this summer.

The cam specs seem to be a secret. Surprised no one has measured it and posted specs. Best I know is when I ordered it from LG I spoke with someone that told me the lift was roughly .630 and duration 245. That's all I got from him. I do know it dyno'd 25 HP more to the wheels than the old cam which was .613/.620 227/235 and 114 LSA. That cam pulled good throughout the curve but the G6X3 is definitely bigger. 475 rwhp vs 450 on the old cam. 1 7/8"x3" headers and ADM cold air are only other mods.

[1sick_eg]

Oh no, I wasn't saying your lifters or your cam was bad. I was saying that I like the hollow stems because of the weight, and that a heavy solid stem intake valve would kill a lifter.

I think you did pretty well getting as many miles as you did out of those trunions with that cam.

Good of you to flush out the old crap as best as you can. Hopefully you're back to normal soon.

[Camarotobeornottobe]

This entire thread might as well have been written in Madrin Chinese, for all I understand of it. I envy you guys.

[cmracing]

What is the length and weight of a solid intake and exhaust valve?

[tadams72]

In case you are wondering what the specs are on the solid valves in the TFS 255's this is what I got directly from them.

"The valves in that head are stainless steel EV12/21-2N. Those valves were designed by us for that head and the valvetrain was spintron tested to 8,200 rpm with no issues. The intake valve is 112.9 g and the exhaust is 96.8 g."

They are heavier than the stock LS3 hollow intake and sodium exhaust. Proper springs are more than capable of controlling them and heavier have been used. Lighter is better when durability is not a problem though plenty are running these heads and valves with success.

[vroomapunk]

My comp trunnion upgrade also failed, a bunch were worn irregularly, and the side of one actually broke off, but the snap rings held the needle bearings in place.

But, I did have too much spring pressure then, so its not all the trunnions fault. I have since gone with a new cam, weaker springs, and did the BTR trunnion kit. Honestly, I think the actual trunnions are better in the comp kit (BTR ones were kinda machined crappy), the bearings seem identical between the two kits, the bolts are better in the BTR kit, and the snap rings are better in the BTR kit. Wish I could have combined the two.

[1sick_eg]

Originally Posted by tadams72

In case you are wondering what the specs are on the solid valves in the TFS 255's this is what I got directly from them.

"The valves in that head are stainless steel EV12/21-2N. Those valves were designed by us for that head and the valvetrain was spintron tested to 8,200 rpm with no issues. The intake valve is 112.9 g and the exhaust is 96.8 g."

They are heavier than the stock LS3 hollow intake and sodium exhaust. Proper springs are more than capable of controlling them and heavier have been used. Lighter is better when durability is not a problem though plenty are running these heads and valves with success.

They are much heavier. The stock intake valves weigh 89g. It's not the spring so much as the lifter I'd be worried about. There have been plenty of hydraulic lifter failures running the tfs255 heads with the solid stainless valves.

[Firefighter]

Originally Posted by 1sick_eg

They are much heavier. The stock intake valves weigh 89g. It's not the spring so much as the lifter I'd be worried about. There have been plenty of hydraulic lifter failures running the tfs255 heads with the solid stainless valves.

I'm starting to think the smart thing is to just do small bore LS7 heads, PRC has some nice offerings and MAST also but for the money I'd go PRC and the MSD manifold. PRC out the door for around $3K

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