So I have my sbc about ready to be put back on the road, but all of the flat tappet cam doomsaying I'm reading has me considering shelving the truck until I have time to install a roller cam.
This is funny because I don't remember constantly wiping out cam lobes back when flat tappets were the norm. Now that I think about it, wouldn't the chevys flat tappet cam have a similar amount of friction as the shim under bucket design in my R1?
Follow proper break in procedures, run oil with 800+ PPM zinc (any 15w40 diesel spec oil will do) maybe more zinc for significantly stiffer than stock springs, don't worry about it.
You really only see wiped cams in V6/V8 engines with crappy valvetrain geometry and small lifters. Unless you're me, then you wipe a cam in an OHC engine with lifters over an inch in diameter and lobes to match, with good oil in it.
I was planning on running Joe Gibbs' oil in it.
BrokenYugo wrote: You really only see wiped cams in V6/V8 engines with crappy valvetrain geometry and small lifters. Unless you're me, then you wipe a cam in an OHC engine with lifters over an inch in diameter and lobes to match, with good oil in it.
This is the $1499 goodwrench 350 from sumitt, so I assume it has the 0.842" lifters.
I add ZDPPlus additive when I do oil changes on the Mini. No idea if it has helped or not, but with all the money I dropped into the engine and gearbox on that thing, it gives me a little piece of mind.
T.J. wrote: I add ZDPPlus additive when I do oil changes on the Mini. No idea if it has helped or not, but with all the money I dropped into the engine and gearbox on that thing, it gives me a little piece of mind.
Cool i will check that out.
For a Goodwrench 350 with stock cam and springs you could probably get away with modern low zinc oil, just like they did with old low zinc oil up until the mid 1960s. I went and looked up the installation/break in guide and they make no mention of special oil, just "quality conventional 10w30/10w40" and the usual idle at 2500 rpm for half an hour to break the cam in. There would be huge warning boxes for an engine with a warranty that needs a specific oil to not kill itself in 100 miles.
If Goodwrench say to go with just a quality oil, that's what I'd do. They wouldn't risk massive claims from people wiping out lobes by recommending questionable break in procedures. For peice of mind, you could contact Goodwrench and ask if break in procedures have changed.
My dad ran Valvoline VR1 in his 67 Mustang/289. He never had a problem, but then again he wasn't pushing it too hard.
BrokenYugo wrote: For a Goodwrench 350 with stock cam and springs you could probably get away with modern low zinc oil, just like they did with old low zinc oil up until the mid 1960s. I went and looked up the installation/break in guide and they make no mention of special oil, just "quality conventional 10w30/10w40" and the usual idle at 2500 rpm for half an hour to break the cam in. There would be huge warning boxes for an engine with a warranty that needs a specific oil to not kill itself in 100 miles.
It's all stock for right now. I was about to order the Howard's CL112571-12 until I noticed everyone saying that flat tappets are the devil.
In reply to slowride:
That's what I was using in it the couple times I have driven it. Have heard since then that the Joe Gibbs stuff was even better.
Aggressive flat tappet cams suffer from lower quality hydraulic lifters. No OE uses them anymore, so the quality dropped. Good oil, designed for intended use, and all should be ok.
In the 80's, I changed a boatload of late 70's 305 cams. GM dropped the quality until they started to scrub. By the early 80's, they had hardened them up again.
On an upgraded cam you'd probably want to run something like VR1 or diesel spec oil. There's a lot of misinformation out there about zddp content of motor oil, to make a long story short, 1200ppm is all you'll likely ever need (and more like 800 for stock low power stuff), past 1400ppm phosphorous you actually see increased wear.
ZDDP isn't the be-all end-all and adding it to modern oil formulas intended to work without it can make pressure handling ability WORSE, not better.
Use Joe Gibbs or Brad Penn oil and don't add any extra junk to it. We retail Brad Penn and use it in all older vehicles.
That said we ALSO as policy don't install new flat tappet cams anymore, all engine builds get rollers. The simple reason is, sometimes even if you do everything right you flatten a lobe on break-in, and then you have to tear the engine down to a bare block including knocking out all core plugs, and clean EVERYTHING to get the debris out, and if you are lucky you didn't wreck the bores and pistons from the flak. Although usually the pistons are junk and you have to rehone the cylinders. A few hundred bucks more for a roller is cheap insurance versus another $3000+ to pull and rebuild the engine again.
If the cam survives break-in then they aren't "ticking time bombs". Just use good oil meant for high performance flat tappet engines. Modern formulation Diesel oil is not what it used to be, don't blindly trust it, Diesels have roller cams and concerns for catalyst life now too so the modern oils aren't as flat tappet friendly.
Blue bottle STP plus Delo gets you over 1300ppm zinc.
Mobile 1 20W50 for big twin motorcycles has high "magic stuff" in it.
Dr. Hess wrote: Mobile 1 20W50 for big twin motorcycles has high "magic stuff" in it.
I noticed this months ago and put it in my Spitfire (car not bike). I was hoping the additives in it for motorcycle clutches weren't bad mojo for the Spit engine. I
i run 10W-30 Mobil 1 High Mileage oil in my Camaro with a biggish (.490 and .510 lift, according to my dial indicator) flat tappet cam with matching heavier springs and have had no problems with it since i put that engine in my car in the spring of 2014.
for a stock Goodwrench 350 with springs that you can likely push down with your bare hands, i wouldn't worry about it beyond running a good name brand oil, but the M1 oil is $21 for 5 quart jugs at Wal Mart these days so it's not too expensive to run the good stuff.
In reply to spitfirebill:
The stuff was made for/marketed to Harley big twins. They do not share motor oil with clutch oil post 1985. Up to 1985, the clutches were mostly dry, but motor oil was pumped into the primary.
A lot of performance people are running the stuff in the cars. Popular in Elise (Toyota 2ZZGE) and Esprit Turbo applications.
Mobil 1 is kind enough to disclose the phosphorous/zinc content of their oils.
https://mobiloil.com/~/media/amer/us/pvl/files/pdfs/mobil-1-oil-product-specs-guide-2016.pdf
etifosi wrote: Blue bottle STP plus Delo gets you over 1300ppm zinc.
Last I checked STP has lower zinc content (like 600ppm) than Delo/Delvac/Rotella.
I've been running a flat tappet Howard's cam (231°@050/0.470"/108LSA) and their recommended 340lb springs, for three years in my daily driver. I use Lucas "Hot Rod" oil which is high in Zinc.
It doesn't ~appear~ to be eating the cam lobes.....
Amsoil has a high zinc ,high phosphorus oil for flat tappet cams.
Called Z-Rod synthetic oil. 10W-30 and 20W-50
Pet peeve: It's more the phosphorus that provides the protection, like phosphate coating. People zee ZDDP means Zinc di-ohwowthosearelongwords and just shorten it to Zinc.
It's kinda like when people say "stall converters". Or use an apostrophe where their shouldn't be one.
Thanks for all the replies guys. Still conflicted though.
My zx10r has a shim under bucket bucket adjusters like this: 
It turns 15,500 rpm and doesn't require any special oil. How is the friction produced from that kind of setup any different than my sbc flat tappet? Neither one uses a roller to ride on the cam lobes.
Knurled wrote: That said we ALSO as policy don't install new flat tappet cams anymore, all engine builds get rollers. The simple reason is, sometimes even if you do everything right you flatten a lobe on break-in,
How often would you say that happens, is it rare?
Which style of retrofit lifter would you recommend?
Or these:
You'll need to log in to post.
