Hi guys
Just rebuilding a 99SS for a friend. The camshaft is definitely longer duration than stock SS and a little more lift. It is stamped as P.D702 with WEC below. It appears to be on a stock core as it has the standard casting marks too T2219#3.
Paul Dunstall?
Anybody able to ID?
Paul
Unless you are fitting new …
Unless you are fitting new aftermarket conrods I would avoid attempting to tune this motor. The original rods were last made in the early 1960's, so 60 years old now. An alternative would be to fit a 650/750 motor or even fit a 650 crank/rods/pistons into a modified 88/99 case. 99 barrels and head can be used with minor mods so the changes are pretty invisible. Or go for reliability with low comp pistons and a std dommy QR cam. I don't think the original rods were particularly fragile ,Its just they were never expected to last this long. My rods have survived a seizure (the usual cause of breakage I think) but are now a worry.
- Log in to post comments
Cam
Thanks guys
As you say a stock SS cam is more than hot enough for the 99. The bike is a genuine 99SS.
I notice that it also uses the shorter 650 valve springs according to the parts book as opposed to the 2" springs used with the QR cam. I'll see what cam the guy wants to use and fit the relative springs.
Incidentally I have also found another cam marked NH2 that appears to be the same lift as an SS cam but more "pointy". I thought Norman Hyde but I don't think he made Norton cams.
Paul
- Log in to post comments
PD is certainly consistent with 3 cams that I profiled and can be seen here:
http://atlanticgreen.com/camsurvey.htm
WEC sufix is also consistent with the other twin chain core cam from a 20M3 engine.
A stock 22729 SS twin chain core cam seems plenty hot. So more lift and longer duration is something I would not desire in a street engine. I have not seen that number before and would suspect it's application in a small port head 99.
If you were in the US, I'd have you send it to me for a thorough profile measurement...
good luck