Hasd anybody had success running flat tappet cams nowadays?
#1812056
04/26/15 12:40 AM
04/26/15 12:40 AM
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Joined: Jan 2003
Posts: 4,270 Morrow, OH
markz528
OP
master
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OP
master
Joined: Jan 2003
Posts: 4,270
Morrow, OH
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Builder had messed up the push rod length in my daughter's 67 Coronet 500. This led me to changing the lifters in the engine.
I have 26 runs on the engine and maybe 200 street miles.
So I pulled the lifters out. 6 or 7 lifters are bad with 2 to 3 of those being pretty bad. No idea on the condition on the cam, but my bet is it is hurt. I will be calling comp cams on Monday to get their opinion. My current plan is to go ahead and put it back together with the new lifters put some runs on it and limit street miles.
I guess I will put a hydraulic roller cam in it when I put the motor in the GTX.
I thought I did everything right. I was running 20W-50 Valvoline VR1 racing oil.
AAAARRRRGGGGHHHH!
Is anyone having luck running flat tappet cams nowadays?
67 Coronet 500 9.610 @ 139.20 mph 67 Coronet 500 (street car) 14.82 @ 94 mph 69 GTX (clone) - build in progress......
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Re: Hasd anybody had success running flat tappet cams nowadays?
[Re: goldmember]
#1812073
04/26/15 01:10 AM
04/26/15 01:10 AM
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Joined: May 2003
Posts: 15,487 Florida
scratchnfotraction
I Live Here
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I Live Here
Joined: May 2003
Posts: 15,487
Florida
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I have never used comp cams or lifters but have read lots of post on wiped cam lobes/lifters the last 10 yrs. used a few set of springs though.
I just installed and did the break in on a Hughes 440 whiplash flat tappet cam.
used the supplied joe gibbs break in lube on cam lifters with rotella 10w30 for break in for 35-40 mins.
30 min cool down then changed oil/filter to amsoil 100% full syn high zinc 10w40. 200 miles and all is well and quite.
Last edited by scratchnfotraction; 04/26/15 01:11 AM.
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Re: Hasd anybody had success running flat tappet cams nowadays?
[Re: markz528]
#1812077
04/26/15 01:17 AM
04/26/15 01:17 AM
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Joined: Feb 2003
Posts: 1,306 Laveen, Arizona
GTSDart340
pro stock
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pro stock
Joined: Feb 2003
Posts: 1,306
Laveen, Arizona
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I've had a lot of problems with crane lifters... I'm about to replace the final eight of them in my Dart. Never seem to hold pressure, once the cars hot they clatter like crazy!
1949 International KB-2 "Mater" - 302/T5
1968 Dodge Dart GTS "The Drat" - 340/727
2006 Dodge Magnum R/T - Hemi
2016 Dodge Durango Limited - 3.6
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Re: Hasd anybody had success running flat tappet cams nowadays?
[Re: scratchnfotraction]
#1812080
04/26/15 01:22 AM
04/26/15 01:22 AM
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Joined: Nov 2003
Posts: 36,040 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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correct breakin oil (enough zinc). reduce spring pressure. make sure lifter/bore clearance is correct ahead of time. goose the throttle many times during the breakin. correct preload. other than that the metallurgy is out of your hands. EDIT what happened with the pushrod length problem?
Last edited by RapidRobert; 04/26/15 01:23 AM.
live every 24 hour block of time like it's your last day on earth
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Re: Has anybody had success running flat tappet cams nowadays?
[Re: markz528]
#1812108
04/26/15 02:30 AM
04/26/15 02:30 AM
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Joined: May 2008
Posts: 5,399 Aurora, Colorado
451Mopar
master
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master
Joined: May 2008
Posts: 5,399
Aurora, Colorado
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besides the oil, the lifter bores should be checked and burnished to make sure the lifters rotate correctly, then break-in the cam with additional oil additive with only the outer springs if using a dual spring setup. After the cam break-in install the inner springs.
If the lifters were bad, then chances are the cam is also shot. The metal shavings from the wiped out lifters and cam lobes can scratch the cylinder walls, bearings and oil pump.
I let a cam go to long with a bad lobe lifter and had to have the engine hones, new rings, bearings and oil pump.
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Re: Hasd anybody had success running flat tappet cams nowadays?
[Re: RapidRobert]
#1812235
04/26/15 12:08 PM
04/26/15 12:08 PM
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Joined: Jan 2003
Posts: 4,270 Morrow, OH
markz528
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Morrow, OH
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what happened with the pushrod length problem? Its a long story but the pushrods were too short and the threads on the rocker adjuster nuts were not fully engaged. Also the preload (hydraulic lifters) was not properly set. We were making T&T runs and all of a sudden the car started going faster and faster. In 3 runs it dropped around 0.8 seconds! On the final run it lost the water pump belt and overheated. When it overheated 2 pushrods fell out. That's when I found out the valve train was a mess. I found several cups in the lifters with cracks. At that time the lifters looked suspicious but not real bad. 26 runs later the lifters are shot. I have put upteen cams in my cars over the last 35 years. Never had on fail due to break in until now. There is definitely something to be said for today's oil and metallurgy. I'm going with a hydraulic roller..........
67 Coronet 500 9.610 @ 139.20 mph 67 Coronet 500 (street car) 14.82 @ 94 mph 69 GTX (clone) - build in progress......
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Re: Hasd anybody had success running flat tappet cams nowadays?
[Re: markz528]
#1812255
04/26/15 12:35 PM
04/26/15 12:35 PM
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Joined: Jan 2003
Posts: 12,096 Benton, IL.
DaveRS23
Special needs idiot
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Special needs idiot
Joined: Jan 2003
Posts: 12,096
Benton, IL.
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I have a flat solid (251*/264*) in the Cuda. Been in there for 5 years or so. Mostly street with a little strip time. The car sees 1,500 miles or so a year.
Out of a dozen FT cams or so the last 15 years, I have had 2 fail. One didn't survive break-in and the other wore down several lobes after a couple of years.
I am really torn as to which lifter to use on my next build. There are as many horror stories about the rollers as there are about the flats. Right now, I am leaning towards the flats again. If going roller were to virtually GUARANTEE no failures, I would spend the coin and go that way. But there are no guarantees given the number of roller failures that I read about here and on the 'bullet.
Master, again and still
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Re: Hasd anybody had success running flat tappet cams nowadays?
[Re: markz528]
#1812675
04/26/15 11:37 PM
04/26/15 11:37 PM
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Joined: Jan 2003
Posts: 75,020 U.S.S.A.
JohnRR
I Win
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I Win
Joined: Jan 2003
Posts: 75,020
U.S.S.A.
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What do you mean by "the lifters are shot" ? No problems here with a flat tappet other than one potential comp SHELF cam that could have been on it's way to going Flat, I'll only use a Comp now if it's a CUSTOM grind, Comp does not grind their SHELF cams , they outsource ... so I'm told by a reliable source.
running up my post count some more .
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Re: Hasd anybody had success running flat tappet cams nowadays?
[Re: markz528]
#1812728
04/27/15 12:10 AM
04/27/15 12:10 AM
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Joined: Jan 2003
Posts: 27,468 So Cal
autoxcuda
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 27,468
So Cal
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Running a comp 274-S solid off the shelf grind with comp lifters. .502/.511 lift minus lash.
Run Castrol 10/30w with Justice Brothers Heavy Duty Vehicle oil additive.
6500 miles so far.
Last edited by autoxcuda; 04/27/15 02:54 AM.
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Re: Hasd anybody had success running flat tappet cams nowadays?
[Re: markz528]
#1812807
04/27/15 01:19 AM
04/27/15 01:19 AM
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Joined: Jul 2006
Posts: 4,319 Puyallup, WA
StealthWedge67
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master
Joined: Jul 2006
Posts: 4,319
Puyallup, WA
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Been running a solid flat tappet in my 451 for 5 years now. Engle cam, lifter and spring package. Broke in on Brad Penn break in oil, been running Lucas Hot Rod 10w-30 with a zinc additive since then. No issues.
Prior to this motor, I ran a hydraulic flat tappet in my 383. No issues there either.
LemonWedge - Street heavy / Strip ready - 11.07 @ 120
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Re: Hasd anybody had success running flat tappet cams nowadays?
[Re: markz528]
#1813339
04/27/15 08:37 PM
04/27/15 08:37 PM
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Joined: Jan 2005
Posts: 3,699 Newport, Mi
Evil Spirit
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master
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Posts: 3,699
Newport, Mi
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I'm a firm believer that many "cam" failures are actually caused by bad break-in techniques. I've had good luck using Brad Penn break-in oil and the old GM EOS or equivalent Zinc additives. One thing I do RELIGIOUSLY is once I shut the engine off on the initial break-in - I do not restart it until it cools fully. IMO this helps "temper" the cam lobes. Personally I think too many first starts are "media events" with a half dozen buddies, too much beer, and the hot engine gets restarted every 20 minutes like a Chuckie Cheese show.
I had a hydraulic cam that kept on having lifter bleed down issues. I tossed a new set of mechanical lifters in it, ran it through another break-in, and ran it for about 25K miles before we hurt it with a bad NOS fuel solenoid. Yeah, I know - different ramps, will never work - whatever.
Free advice and worth every penny... Factory trained Slinky rewinder.........
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