Which camshaft?

[weim55]

If you were going to have the engine apart for a complete reseal, while you have the intake off, remove each a lifter one at a time and check the lifter base for condition-wear. Make sure and reinstall the lifter in the same hole as you check each one. If all 16 pass in good condition and you had no valvetrain noise before disassembling I wouldn't change the cam, just leave it alone. There's too much risk with junk aftermarket camshafts and lifters + issues with zinclless oils. You can't beat the quality of those original GM components if they are in good condition.

You've mentioned budget-daily driver a couple times, I wouldn't open this can of worms unless it's absolutely necessary. It's not worth the few extra horsepower for the risk. I speak from a lot of experience with this.......

Steve weim55 Colorado

[trac209]

Originally Posted by weim55

If you were going to have the engine apart for a complete reseal, while you have the intake off, remove each a lifter one at a time and check the lifter base for condition-wear. Make sure and reinstall the lifter in the same hole as you check each one. If all 16 pass in good condition and you had no valvetrain noise before disassembling I wouldn't change the cam, just leave it alone. There's too much risk with junk aftermarket camshafts and lifters + issues with zinclless oils. You can't beat the quality of those original GM components if they are in good condition.

You've mentioned budget-daily driver a couple times, I wouldn't open this can of worms unless it's absolutely necessary. It's not worth the few extra horsepower for the risk. I speak from a lot of experience with this.......

Steve weim55 Colorado

Idk about today’s cams being any worse than one gm used. If a cam goes flat it’s 95 percent of the time it wasn’t broken in properly. I have only ever seen one cam go flat and the guy who’s engine it happened in never even broke it in and even then it was just one lobe that went. For a few bucks you can have a cam treated to be more durable for break in. If you use proper break in oil and the engine fires up quickly and up to 2000 rpm for 25 min or so the cam should be just fine. In fact I’ve never even added a zinc additive or special oils once the cam is broken in. Just good oil change intervals and you can buy a zinc additive for extra insurance easily enough.

[weim55]

Originally Posted by trac209

Idk about today’s cams being any worse than one gm used. If a cam goes flat it’s 95 percent of the time it wasn’t broken in properly. I have only ever seen one cam go flat and the guy who’s engine it happened in never even broke it in and even then it was just one lobe that went. For a few bucks you can have a cam treated to be more durable for break in. If you use proper break in oil and the engine fires up quickly and up to 2000 rpm for 25 min or so the cam should be just fine. In fact I’ve never even added a zinc additive or special oils once the cam is broken in. Just good oil change intervals and you can buy a zinc additive for extra insurance easily enough.

You are correct on all counts. In the old days I used these breakin procedures and never had a single issue on any flat tappet motor for 20 years of building engines. In the last 10 years i've lost close to 10 camshafts using a perfect break in procedure, proper cam prelube and proper oil with correct pressure-zinc additives. The issue is garbage after market camshaft and lifters.

I agree with you on a typical flat tappet engine that has a good cam with proper break-in the zinc additives aren't all that necessary on a typical old mid high mileage V8. The valve springs are so weak with so little seat pressure even today's motor oil's do the job just fine. I've had plenty of customers that have run the newer oil's unknowingly for years with no issues. I won't run any flat tappet engine without a proper zinc oil but that's me.

Steve weim55 Colorado