rebuilding LS6 for chevelle

[Crossbreed383]

I responded to a thread here not long ago explaining the issues with most cam failures these days but no one seemed responsive ??
Oh and I work at BTR and do all the custom cam work as well as run the Spintron and engine dyno from time to time when help is needed .
We are grinding cams inhouse but aren't doing anything BB although I spec and have them ground for customers all the time
Nick E.

[RobR]

Nick, i’m glad you posted here. I was looking for your other post you mentioned to ad to this thread. it’s one of the main reason these problems exist in flat tap at cams. Deviating from the cam core shape when changing centerlines and lobe shapes making hardness treatment very thin in some areas.

If you can find that post it’s worth reposting here. It’s very insightful and worth reading. thanks, Rob.

[RobR]

Nick’s post:
The issue IMO is more to do with insufficient case hardened depth on the cam cores being used. The issue is when the case depth on the nose isn't enough and this is magnified because of spring psi being highest at over the nose of the cam, than on the base circle of the cam .
Certain companies use the same UGL( unground lobe ) cam cores for a multitude of cam valve events, pt numbers , etc . The issue lies in that you harden the lobes during heat treat, but when you try to cut the more than one cam profile, using multiple centerlines or lobe lift( base circle) on the same core ,you end up grinding away too much or even going through the heat treat in some spots.
If the use a specialty UGL for each specific cam then the case depth is set at XX mm of what it needs and you after final grinding you are left with sufficient heat treat depth.
We see it all the time here .
Thanks

[Igosplut]

Originally Posted by RobR

Nick’s post:
The issue IMO is more to do with insufficient case hardened depth on the cam cores being used. The issue is when the case depth on the nose isn't enough and this is magnified because of spring psi being highest at over the nose of the cam, than on the base circle of the cam .
Certain companies use the same UGL( unground lobe ) cam cores for a multitude of cam valve events, pt numbers , etc . The issue lies in that you harden the lobes during heat treat, but when you try to cut the more than one cam profile, using multiple centerlines or lobe lift( base circle) on the same core ,you end up grinding away too much or even going through the heat treat in some spots.
If the use a specialty UGL for each specific cam then the case depth is set at XX mm of what it needs and you after final grinding you are left with sufficient heat treat depth.
We see it all the time here .
Thanks

Best post I've seen on this subject. On the subject of sound, I even wanted forged pistons in the 350 Chevy motor I put in my CJ5 because of the noise. Solid lifters, a cam lope, intake whoop, an M22 whine, the list goes on. Without it, you could be driving anything, and I'd rather stay home.

[COPO]

Originally Posted by Igosplut

Best post I've seen on this subject. On the subject of sound, I even wanted forged pistons in the 350 Chevy motor I put in my CJ5 because of the noise. Solid lifters, a cam lope, intake whoop, an M22 whine, the list goes on. Without it, you could be driving anything, and I'd rather stay home.

Sounds like me back in highschool except I also added a Pete Jackson gear drive to my LT-1 to really make some noise.