Solid flat tappet vs roller on the street ?

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Monza355
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Solid flat tappet vs roller on the street ?

Post by Monza355 » Tue Oct 24, 2017 8:45 am

I’we been wondering which of the two would last longer in a small block street engine ?

Comp cams xtreme street solid roller cams seem to require mild spring pressures. With their 818 pressure fed roller lifters and recommended spring pressures from comp 155 lbs on the seat with 420 lbs open. This would be ran with rev kit as well.

How would a decent solid flat tappet camshaft like their oval track cam 242/250 @.050” with 106 lsa and .507”/532” lift compare on the street with edm lifters for durability and decent springs like 150 lbs on the seat and 350 lbs on the nose ?

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Re: Solid flat tappet vs roller on the street ?

Post by Walter R. Malik » Tue Oct 24, 2017 9:43 am

Monza355 wrote:
Tue Oct 24, 2017 8:45 am
I’we been wondering which of the two would last longer in a small block street engine ?

Comp cams xtreme street solid roller cams seem to require mild spring pressures. With their 818 pressure fed roller lifters and recommended spring pressures from comp 155 lbs on the seat with 420 lbs open. This would be ran with rev kit as well.

How would a decent solid flat tappet camshaft like their oval track cam 242/250 @.050” with 106 lsa and .507”/532” lift compare on the street with edm lifters for durability and decent springs like 150 lbs on the seat and 350 lbs on the nose ?
There is good sound reasoning for either camp of thought so, it then becomes a personal decision.
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tenxal
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Re: Solid flat tappet vs roller on the street ?

Post by tenxal » Tue Oct 24, 2017 10:33 am

Lots to like about both, though the flat tappet will require a little more attention to the zinc content of the oil.

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Re: Solid flat tappet vs roller on the street ?

Post by F-BIRD'88 » Tue Oct 24, 2017 10:57 am

My money goes on the XR solid street roller.. I like to set the lash a little tighter than the cam card says.
For a lot of reasons. If you want it ground on a different LSA just call Comp...
You probabily won't need the rev kit. But if you want it go for it.

A good motor oil that has a bit of Moly or added bit of moly in it will help BOTH CAMS.

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Re: Solid flat tappet vs roller on the street ?

Post by stealth » Sun Oct 29, 2017 12:08 pm

Solid flat will NEVER cough out needle bearings
Solid flat is about 1/4 the price
Solid flat MIGHT be down on hp compared to solid roller
solid flat MODERN PROFILE does not require overkill on valve springs


Zinc is not an issue...reasearch zinc in oil.

Hint zink content is not about amount available for protection...it’s about longevity of protection...

Look into motorcycle oils ...definitely not diesel oil..
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