[Tigers] Roller 289

[Smit, Theo]

Hi Tony,
You shouldn't use a roller lifter with a non-roller cam because (besides
the cam hardness issue) the cam lobe profile is totally different. A
flat tappet cam is designed to push a flat surface up at the right rate,
while a roller cam is designed to work against a radiused surface and
still achieve a comparable lift profile to what was originally obtained
with the flat tappet interface.

If you compare a roller cam lobe to a flat tappet cam lobe, you'll see
that the roller cam tip is a lot more rounded compared to the flat
tappet cam, even though the lift-at-the-valve profile might be quite
similar.

Cheers,
Theo



> -----Original Message-----
> From: tigers-bounces at autox.team.net
> [mailto:tigers-bounces at autox.team.net] On Behalf Of Tony Somebody
> Sent: August 18, 2009 11:34 AM
> To: tigers at autox.team.net; Jeffrey Nichols
> Subject: Re: [Tigers] Roller 289
>
<snip>
> requiring change if used with a roller cam. Is there a
> problem using roller lifters with a non roller cam because of
> the hardness-like w/ the dist. gear.
> TtT
> _______________________________________________