Weight comparison: solid vs. hydraulic (flat tappet)

[five7kid]

In the process of installing the new Comp XS282S cam in the 396, I took one of the removed hydraulic and one new solid lifter and compared them on a food scale. Granted, not a "certified" or "precise" scale, but at least it gives a comparison.

The hydraulic weighed 100 grams, the solid 80. May not seem like much, but every little bit adds up.

[1970judge]

Hey thats good info i had no idea. But im a hydro man myself. I didnt no you were building a 396? I built one 396 sold to some guy in houston. Last i talked to him he was low 10's with a button and it is in a 2nd gen he said.

[five7kid]

This is what I've been running in the '57 since 1997. It ran in the mid-15's at altitude back then; with minor, progressive changes over the years it ran a best of 13.51 at altitude last October.

Everything I've heard says BBC's like lift. But, they suffer from heavy valves, although mine are the smaller version (2.06/1.72), which limits RPM capability.

Perhaps the next "improvement" will be sodium filled stems. . .

[1970judge]

Well it sufferes on the intake exhaust. In a normal say sbc its hard to get alot of intake simply because it takes more effort to inhale than exhale hence the intake valve being bigger. With a bbc you have bigger valves meaning bigger intake valve meaning even harder to inhale on the intake side. Bbc take kindly to mild cams for than they do heavy duty nasty ones i learned that firsthand on a 440 big block. I got a set of lightweight valves for teh 396 and a mild cam for my 396 although i never turned it over so i wouldnt know how it helped.

[five7kid]

I should have checked the record - it actually pulled off a 13.485 @ 99.49 MPH at 5800' last fall.

Fellow BBC racers with whom I've talked think the cam will be a big step up that the engine will love.

(Just curious, were you sober when you typed the above??? :D )

[1970judge]

yes'r why?

[five7kid]

Must be me. I'm having trouble following it.

[1970judge]

Oh sorry about that lol.

[five7kid]

Got 'er running and took it out for a little test drive last night. Shall we say the tach went where it's never gone before, and without a whimper?

Oh, so looking forward to this season. . .