Power loss from flat tappet

[DarkMesa8]

How much power are you actually losing out of by staying flat tappet vs going roller? My 351W block is flat tappet, and I plan on getting an FTI custom cam regardless wether or not I stay flat or roller.

What kind of number difference is there powerwise?

 

[Stang8URMPRT]

I would say somewhere around 5-10 hp. The benefit of the roller lifter is less friction, and better reliability. Roller cams also have fast ramp rates, which cause valve float... You can get more RPM with a flat tappet cam, also more efficient ramp rates, although they are starting to perfect the roller cam and lifter.

 

[DarkMesa8]

This debate is killing me in my head.

$400 conversion lifters
$325 FTI Cam

Or

$100 New Lifters
$225 FTI Cam

I am really having trouble deciding, that money would be useful paying for a better intake or better headers.

 

[Stang8URMPRT]

I loved the flat tappet in my 83.. With the right valve springs and cam, I had that thing turning 7000 rpms...