Cams are very complex items and the lift/duration numbers don't necessarily
define what the performance will be.
Duration is usually called out at some small valve lift, maybe 0.050", but
can be 0.030" as is a cam that I have. The rate of opening can be a very
significant factor in performance. If the opening and closing ramps are
fast it gives the cylinder more time to breathe than a cam with gentle
ramps while both have the same duration. The cam lift is only the
effective difference between the base circle radius and the radius of the
highest point on the lobe.
As far as I know there are no "NEW" R-16 cams made for improved
performance. All of the R-16 cams discussed in the recent postings are
regrinds including the Nissan 9/6-B1020 and 9/6-B1021 racing cams. Col.
Joe used a couple of cams that were part of a small batch of "Billet" cams.
The billet blanks were made in Southern california and sent to Virginia to
be ground according to info supplied by Col. Joe. The billets were made
from steel instead of cast iron and had a distributor drive gear with a
Chevy design because they didn't have the capability to cut the Datsun one.
It was necessary to run a brass driven gear because of metallurgy.
I am not an expert on cam design but wanted to caution that comparing cam
spec's doesn't tell the whole story. You must trust your cam grinder and
his experience with similar applications.
Stan
==============
At 09:48 PM 2/4/01 -0800, Victor Laury wrote:
>On Rob's page, Col. Joe describes his special grind as Lift .350" Dur 250.
>Compared to the specs below, that would seem way mild. What's up with that?
>
>----- Original Message -----
>From: Gordon Glasgow <glasgow@serv.net>
>To: <datsun-roadsters@autox.team.net>
>Sent: Sunday, February 04, 2001 8:50 PM
>Subject: RE: R 16 Cams
>
>
>Racer Brown 324R Lift .475"; dur. 262 deg.
>Racer Brown 325R Lift .475"; dur. 275 deg.
>
>Gordon Glasgow
>Renton, WA
>
>-----Original Message-----
>From: owner-datsun-roadsters@autox.team.net
>[mailto:owner-datsun-roadsters@autox.team.net]On Behalf Of Henry Bahn
>Sent: Sunday, February 04, 2001 7:39 PM
>To: Teesun68; STAN CHERNOFF; datsun-roadsters@autox.team.net
>Subject: R 16 Cams
>
>
>Some 1600 cams, in increasing order of performance. Anyone know of others?
>
>Nissan P/N 13001-18810; specs unknown
>NISMO P/N unknown; Lift .480"; dur. 300 deg.
>Chambers P/N 250-353: Lift .353"; dur. 250 deg.
>Isky P/N W84N; 6626cc . . . Lift .420"; dur. 266 deg.
>PAECO P/N DS-6000 Lift .367"; dur. 266 deg.
>PAECO P/N DS-6800 Lift .421"; dur. 270 deg.
>PAECO P/N DS-7200 Lift .430"; dur. 288 deg.
>PAECO P/N DS-7800 Lift .434"; dur. 295 deg.
>Tilton P/N unknown Lift .480"; dur. 310 deg.
>
>JH Bahn
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