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Differential/Driveline
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I've used some pretty aggressive hyd & solid cams in the last 25 years from many different brands and I dont have that problem.

If someone wants to spring for a roller setup.. even better. But I just dont have a problem with the other cams.
 

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WFO
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It's no news that a roller profile doesn't give a performance advantage at the small end of the scale. What it DOES offer is greatly increased reliability.

With all due respect to Vizzard- who IS a very knowledgeable individual, for sure- the Crankshaft Coalition wiki has as much if not more info on how to break in a flat tappet cam: Cam installation tips
 

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It's no news that a roller profile doesn't give a performance advantage at the small end of the scale. What it DOES offer is greatly increased reliability.

With all due respect to Vizzard- who IS a very knowledgeable individual, for sure- the Crankshaft Coalition wiki has as much if not more info on how to break in a flat tappet cam: Cam installation tips
Like most already assume, a roller cam does still give an advantage at the small end of the scale.
 

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Been using flat hydraulic cams over 20 years for street driven high traffic vehicles. Never has a lobe gone flat. Tried of hearing about it. Either you did not build it right the first time, or you did not properly break it in. I put the cheapest oil in, that is on sale. It is pretty much all the same stuff. The oil avaible today is fine. Quit blaming your mistakes on something/someone else.

You should not use thick paste assembly lube . Just 30wt oil durring assembly.

If flats are so prone to wiping why do my builds never have this issue? Dont believe in magic or luck, so it is a lie.
 

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WFO
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If you are running RV or stock-ish profiles and stock spring pressures, the chances are increased you will get away w/using just motor oil at break in. But for high performance builds, not using a moly break in lube on a flat tappet cam and lifters can well be suicidal- no lie about it. There's a reason the cam manufacturers include that container of break in lube w/the cam.
 

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I wonder how many of these failures are related to improper cam core heat treatment, budget valvetrain assemblies, and unorthodox assembly techniques and all lumped together on flat tappets and oil. Im not a huge fan of assembling an engine with these new high moly pastes and letting them sit for awhile. Ive torn apart shortblocks and the assembly past can turn sort of 'crunchy'.
Deviating from accepted practice may work for some guys, but if you follow the rules, at least you can have some recourse when it comes to your warranty.

Generally for me; stick to older ramp designs for street cars, and make up for any power 'left on the table' with gearing and smaller tires. If you want a wicked bumpstick, call up Harold Brookshire (UDHarold) and go roller cam.
 

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What is high spring pressure to you, the xe268 was pretty tame. People complained about that cam. I think your right about the fact that im using mild cams. If it is to be street daily all season driven stay away from higher spring pressures at all costs.
 

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Id say on a S.W.A.G (scientific wild arse guess) 130 pounds on the seat and maybe 330 pounds open would be about the limit for most guys. I know some more experienced guys that are probably in the 150pds on the seat and 370 or more open. But when you start pushing those numbers, you better have screw in studs and use break in springs or run a dual spring package and do the break in with just the outers. When you start playing in this territory, your safety net is VERY small, if even existent. Which means, high quality pushrods, and a whole lot of time spent trying to get good geometry. You should probably step up to a quality roller rocker and the proper light weight valvetrain.
Now that you've done all that; you would have been money ahead to go hyd. roller cam and rev kit. Realistically, it depends on your durability needs; if its a roundy round engine, you may be limited to a non roller setup, or have a lift rule etc. If its for a street car that spends its life at sub 5000rpms; a high zoot drivetrain is less critical.

When I was growing up a .525 lift cam was something on the street. Now you can see guys with .700" lift and springs that cost as much as my 1st car
 

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Im not a huge fan of assembling an engine with these new high moly pastes and letting them sit for awhile. Ive torn apart shortblocks and the assembly past can turn sort of 'crunchy'.

I've also seen this. Bought a SBC350 that had been sitting for several Yrs. The assy. lube was so hard I could barely scrape it off in some areas, anywhere air touched it it was crunchy hard :smash: under the Rod/Main caps was still pliable. I disassembled, scrubbed/scraped, relubed & reassembled it.
 
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