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Automotive tire Gas Wood Metal Circle

wiped out a 454, 11 outta 16 not bad …..this was a week after a 351 lost 1…I’m making people sign a waiver after they decline the cost of retro roller. There’s only so much time in the day , I help when I can but ya have to curb the problem somehow. So I say your making a good choice!
 

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What lifters have you been using?
 

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Good choice. Now once you're in there, maybe add some stroke. There's no replacement for displacement. I went to a stroker 396 and never looked back. Most stop at 383. But there's almost no cost to increase stroke from 3.75 to 3.875. Just some additional machining for clearance and a deeper oil pan.
 

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What lifters have you been using?
Pops, they were Delphi both times with a Melling 454 cam and an Engine Works 351 brand from Nickels Performance…I blame it all on their break in procedure the 351 actually told me he didn’t use the zinc. 454 was from a MerCruiser dealer who broke it in per their standards , and not good enough.

The OP is on the right path now, but still needs to remind others of his trauma to spend money up front these days.
 

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If there's anything I've discovered with flat tappet cam and lifter failures it's that it can happen with the finest cam and lifters available, or the cheapest. And even with oils with zinc, or additive, it can still happen. And even when everything was done correctly.
Chances are the more you stick to all the correct procedures, the less the odds are it will happen. But these days it can happen even if you did everything correctly, and used all the best parts.
I too am a roller fan and after a lifetime of flat tappet builds I wont buy them anymore.
One major reason engine life went from a maximum of 100,000 miles before rebuilds to 250,000 miles was roller cams. Even without a cam/tappet failure the wear on the cam and lifters is enough to remove metal. That metal that's normal wear gets pumped through your engine and affects all the bearings in your engine, adding to bearing failure, and loss of oil pressure.
 

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I agree with all statements, but that roller conversion on an older motor is expensive.
I just did my 355 and with Morel lifters and heavy .083 wall pushrods Melling cam $1100. Yes expensive but the 351 was $3800 in out in then another $1800. Relative cost with time and stress to do it potentially twice. 454 was $750 in parts i compensated time.
 

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Going roller is for sure not cheap. But once past the initial cost, there is no downside and a lot of upside.
I can see doing flat tappet on a correct restoration of a special car and engine. But past that, I believe it’s false economy. Just my $.02.
 

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Going roller is for sure not cheap. But once past the initial cost, there is no downside and a lot of upside.
I can see doing flat tappet on a correct restoration of a special car and engine. But past that, I believe it’s false economy. Just my $.02.
I went with a stock cam(melling) Elgin lifters on mine but it’s a bone stock 307 driver. Haven’t fired it yet but put plenty assembly lube and the zinc and breaking in with Rotella 14-40 which also contains zinc and plan to continue to use it. Think I’m going to break it in the old fashion way. Fire it up, warm it up, set timing and carb and drive it and hope for the best
 

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I've never in my over 50 years of messing with flat tappet cams started up a SBC or BBC and not done a 20 minute cam/lifter breakin at around 2500 rpm's. And I've also never lost a cam in any new cam install. But the last flat tappet I did was close to a decade ago, and even then cam failures were fairly common with flat tappets.
Back when all this started it was commonly stated in numerous magazines, and with engine builders, that it was the oil. The lack of zinc was blamed for the failures, so that last SBC I did then got Brad Penn break in oil as recommended by the engine builder who did all the machine work. I broke it in with the straight 30w Brad Penn oil, and then changed out at 500 miles like I always do. Cut the filter open, and checked the oil to see if I saw any sparkles indicating metallic particles, and all was fine. That engine has 14,000 miles of street/strip use, and a lot of full throttle runs down the strip also. I only run Valvoline VR-1 since, and it also has high zinc.
I can't say if it's only the oil, as I've had others tell me they did everything right, and still had flat tappet cam failures. But my personal belief is if you buy quality cams and lifters, and use the right high zinc oil, and break it in, it ought to be OK. But I wont chance it myself again, even though it worked for my engine.
My current engine is a 1990, so it uses a factory roller lifter, which made the lifters cheaper. Howards roller lifters were $265, and the cam was $257. So not much over $500 total. Retrofit are quite a bit more, and I don't understand why since it's really just the links that are extra cost to the cam makers, and they sell far more retrofit cam kits than kits for factory roller motors from what I've been told. I could understand an extra $50-$100 for retrofit, but not the 2x price they seem to be asking.
 

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I think it has to be materials cam or lifters or a combination of both because if you coat the cam & lifters with cam lub & you use oil with zink or zink additive then what else is different from the way we have built flat tappet engines for years. I personally haven't lost a flat tappet cam ever but I've seen plenty that have. Most engines I've built in the last several years have been roller cam LS motors or retrofit SBC or BB builds with a couple exceptions. My L79 corvette around 10 years ago & a flat tappet Lunati in a friends SBC Elcamino a couple years ago. I understand if the cam requires high spring pressures because of its specifications that they could be more prone to break in failures but seems like it's happening more frequently than ever? I also have never done the 20 minute 2500 break in but have kept rpm above normal idle.
 

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I have a few friends that never broke in a cam. They just drove them and never had a problem.
Knock on wood, me either BUT I have never built a motor for myself that had a huge cam, mostly a rv cam or little more as all of mine have been drivers with a little ump!
 
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I've been told by people in the know that many of the cam blanks and lifters are now made in China with inferior materials and quality control (no surprise there). If you have high spring pressures breaking a flat tappet cam in, your risking failure. Best to throw in a light set of springs and change back after break in. Last year I worried about cam failure issues on my newly built 400 Pontiac, but had low spring pressures, so that helped. All good so far with 1500 miles on it.
 
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