rebuilding LS6 for chevelle

[Richls5]

Original LS6 carin my car is tired pulled it to bring in for rebuild. my engine builder is trying to steer me toward a hydraulic roller . Someone along the way put a flat tappet hydraulic lifter cam. I drive the car maybe 2-300 miles a year Id like to go to a solid roller to be more correct but hes really trying to steer me toward hydaulic just getting others thoughts

[Too Many Projects]

If you don't plan to twist the engine to it's limits, I would go with the hydraulic roller in a heartbeat. Less maintenance for you and just as reliable. The hydraulics would still work fine at 6,500 anyway...

[Tuna Joe]

I’m in the process of rebuilding my 1969 L89 and I’m going to go with a hydraulic roller.
I’m going to follow One Stop Restoration’s advice and go with Erson Cams.

[big gear head]

I just love a good flat tappet solid. Be careful with a solid roller on the street. Some of them don't do well. I had one in my car for a few years and I got tired of replacing distributor gears and the rollers in the lifters were going bad.

Just remember, it's YOUR decision. Don't let someone talk you into something that you don't really want.

[napa68]

A flat tappet solid should be no problem. The engine builder needs to check for proper rotation of the lifter in the bore to begin with. EDM lifters have improved the landscape of the flat tappet discussion significantly.

My parting thought on the conversation is this......
These are getting to be very expensive cars. I myself, want the car to be authentic. That includes the sound of solids.

[Richls5]

Originally Posted by big gear head

I just love a good flat tappet solid. Be careful with a solid roller on the street. Some of them don't do well. I had one in my car for a few years and I got tired of replacing distributor gears and the rollers in the lifters were going bad.

Just remember, it's YOUR decision. Don't let someone talk you into something that you don't really want.

yeah im aware ive just been using this family to build motors for over 20 years and hes never steered me wrong. this is the first stock motor hes done everything has always been improved over stock

[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

[SS427]

Flat tappet cams have been an issue for many years now but I would try and find one of the few people that are grinding their own cams. There are names out there that can be trusted who are making good cams right now but don't use any of the major cam manufactures as I have had no luck with any of them. The solid lifter sound is what makes the LS6 Chevelle stand out. Quieting that cam ruins it for me. Like taking the whine out of an M22 or the sound of an Rolls Royce Merlin. Silence it and its just another engine.