chevy406

I've been daily driving Corvettes since 2005. My '99 FRC has 435k miles and now my 08 Z06 has 125k miles. It has been my experience that aftermarket cams/lifters are lasting about 80k miles before wearing lobes and/or lifter rollers.
I recently removed the Cam Motion Titan 2 cam (232°/245° .648"/.639") from my Z06 after 75k miles. Lobes aren't terrible, but there is some wear (valve train was starting to get louder). I haven't pulled the Johnson lifters yet.

1. Are other people experiencing similar wear with aftermarket cam longevity?
2. Has anyone found a cam with soft lobes and enough overlap to bleed off some compression (for 93 octane)?

I tuned my car for excellent driveability with the Titan2 cam, but it would be nice to replace it with something that lasts longer than 3 years. I don't "need" 585 rwhp, but it's hard to get excited about stepping power down with a mild lobe. Maybe 3-year valve train life is just a sacrifice to daily driving a hot rod. My '99 Corvette had 6 different cams over the years. The steering rack bolts are about rounded off.

Oh yeah, before I forget - don't use locktite on the cam plate bolts. Torx head bolts suck.

grinder11

I haven't reached 80,000 miles on any aftermarket cam I've owned, so I can't comment on that. However, using loctite on the cam plate isn't any problem. They come out easily if you use one somewhat special tool: HEAT!! Even a hand held propane torch will work. Simply hold the flame on the bolt face/head for maybe 10-15 seconds, and they come right out. Technically, you are correct. I was taught in my apprenticeship that you shouldn't use Loctite on flat head screws, that the increased friction area of the angled seat will hold them. I like a little insurance in this application, so I use blue (removable) Loctite. Usually, you heat the metal around the threads. In this case, just the face or head will work.......

SPDKLZ1

I have a cam with similar lift to the Titan 2. How many sets of valve springs did you go through during those 75k miles?

REDZED2

..go with something like Texas Speed's easy on the valvetrain .635" lobes . TSP stage 1.2 228 240 114. or 2.2 234 246. 112.5 probably the best for what you want. JMO ..anything smaller won't satisfy your wants.

AzDave47

I have a Katech K501 cam .659/.660, 593 rwhp. Cam is good after 24000 miles. I had the valve springs and Ti retainers replaced at 22K mile. I have Katech TiMo intake valves and OEM exhaust valves so the springs (PSI 1511) are not that hard on the valve train, something like 130 seat pressure when new. I run a 7300 RPM FSO.

REDZED2

That's a good bigger cam but quite dated for 2022. IIRC isn't that a Comp cam grind? BTR are also hugely proven. Custom or stage 1-3. Tooley is an engineer. His LONG Youtube vids boggle your mind.

Cheers
Katech has their newer K502 that replaces the 501 with "much smooother lobes" as they say on their website. https://shop.katechengines.com/produ...k502-camshaft/

chevy406

I'm not buying into the marketing of smoother lobes when they decrease duration and hold the same or more lift. That just means high acceleration rate on and off the lobe, which is what I want to avoid. The noisy valvetrains we are so accustomed to from LS engines takes a toll on the cam - lifter interface.

Maybe different lubrication would increase longevity? I've stubbornly continued with 5W30 Mobile 1. I could be convinced to change if someone else pops in with documented improvement using a prettier color oil.

Spdklz1 - in the past I used to swap valve springs after 30k -40k miles. The last two rounds I've gone 75k to 80k on the same springs. I haven't tested them yet but it would be interesting to see spring pressure after 75k.

I got to this same point on the 6th cam in my '99. I ended up selecting a Comp grind with upper .5xx" lift. Eventually broke a lifter so I didn't get to see how far that setup would go. Guess I'll call BTR or Cam Motion to discuss.

AzDave47

Another fellow (Hib Haberson) has a build smaller than mine and does not run the engine nearly as hard as I run mine. His PSI 1511 springs started out at 130 and were down into the 112-115 rang after 20K miles. Unfortunately I never got the "after 22K miles" numbers on my 1511 springs. Reving to 7300 RPM, it doesn't make sense to risk it. The 1511 springs are fairly lightweight beehive springs, but all my valve-train is lightweight as well.

REDZED2

Since the OP has his own stance. A talk with Tooley would be a very good thing. 👍

Apocolipse

Chances are that the wear you are seeing on the cam lobes is due to loss of valvetrain control with springs that have seen 75k miles. Had you replaced springs at decent intervals you wouldn’t have that wear.

chevy406

I accept your admonishment. I will follow up with spring pressure measurements after I get the heads off this weekend. Can we truthfully say we have proper valvetrain control when there is audible noise with most aftermarket cam installations?

I had a healthy conversation with Cam Motion. They requested pictures of my cam - don't get too many opportunities to see LS7 cams with 75k miles on them. I must say it is very nice having a conversation with the director of marketing, and the opportunity to work with them on profiles for high mile driver applications.

Unfortunately CF isn't accepting my picture uploads. I'll work on that later.

I appreciate comments and hopefully don't come across as too bull headed. I do have my opinions. But also please understand that my application is for endurance, commuting to work. Horsepower is important, but primarily I am interested in street manners and endurance. I do EFI calibrating in the evenings after my day job, so having a lopey idle C6 makes a good conversation piece and gives me opportunity to try different strategies over wide range of driving conditions. Plus I like driving Corvettes every day. I will say it does terribly in snow.

acroy

good on you for putting so many miles on the cars. I am interested in updates. I do wonder if more frequent spring changes would have any effect. I also suggest think about going to M1 OW40, it has a lot more of the good metals in it.

v8sten

Cam will be fine, the wearable items will be the valve springs. plan on replacing the springs every 25k miles.

<<< in this C6Z I had a BTR Stg 4 NA Cam and drove it daily. I put about 38k miles on it before I sold it. I replaced the springs at 30k miles after the cam swap. I had the BTR .660 springs on it with Ti retainers.

Apocolipse

Sounds of valves closing is not indicative of a valvetrain out of control. As you increase ramp speed you will increase the rate at which the valve shuts, which increases sound, but it’s still under control. When valvetrain is out of control it will lob and bounce on the nose of the camshaft profile / right after the nose on the close ramp and be seen as wear / pitting. This means the valvetrain was very unhappy.

Josh M

Wow 435k miles on any car is definitely getting your money's worth! Thats awesome!

Z.06

This may skew your statistics but my experience for cam life was over 5 years, but less than 16000 miles. This was a Comp Cams grind with 114 deg LSA and inlet/exhaust duration of 228/248 deg with lifts of 0.623" and 0.652" at the valves. Six cam loads had failed and one lifter, all within 16000 miles. As best I know, the shop I used, which was well known and reviewed on CF selected excessively stiff valve springs for the application, which eventually resulted in cam lobes being destroyed and the eventual failure of the camshaft.

Should this data be used to define the camshaft life for aftermarket camshafts. Well that depends on your viewpoint. I think my situation was common for owners using known shops to install aftermarket cams in their cars, and it seems like the best selection was not done by the vendor. Will you fare better than I did???

Realizing that I would have to replace the camshaft and the lifters, I opted for a more docile camshaft, a CA116 grind. While I knew I was giving up some peak HP, it was worth it to me to get rid of the cowl shake at traffic lights. This also improved WAF (wife acceptance factor). First chance to look at the CA116 camshaft came after another 20,000 miles. This time cam looked great, but valve guides and valves were all toast, so heads were rebuilt again. So, second time around, the camshaft was absolutely fine and was reinstalled in the engine for more duty.

Steve

449er

I guess that the moral of this story is that you will have to accept more valvetrain wear & maintenance from aftermarket cams

AzDave47

Spring pressure enters into this also. A big lift cam with heavy SS valves and heavier rocker arms requires a lot of spring pressure to control float. When I did my K501 I kept the valvetrain light and the PSI 1511 springs, tested to 7800 rpm are rated at 130 psi seat pressure, modest compared to some of the duel spring setups I have read about here. At ~600 rwhp mine is a good build but not as big as many on the forum have done.

Apocolipse

Uncontrolled valvetrain is the evil here - sure spring pressure adds greater psi on the roller contact area but realistically that’s not going to wear it out like lofting does.

acroy

Really interesting information in this thread, thanks for posting. Not all that many people run big cams for many miles, and document the results. I do wonder what the cam manufacturers stance would be on best practices of spring pressure, oil type, spring changes, etc.