Camshaft ?’s

vansmetal

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I was looking through the manual by Hans Pahl and noticed a few extra parts on camshaft pic. Anyways, I’ve included the parts pic for reference of a ‘75 and ‘81(which is what I have). I noticed my camshaft has a hole for a dowel pin but it only shows that a dowel pin is used in the 75 parts pic and I’m sure other years, but not in ‘81…so do I need it or not? Also, I circled in red a few spots that aren’t perfect per say, but I’m assuming it’ll be ok since the camshaft is a cast part or at least that’s my understanding? My big question is…do all I need to put on my camshaft is the 4 bearings and 2 oil seals? Mystery question is does anyone know what HRS means that is engraved and I can’t make out the rest??? Thanks to all who can help!
 

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Pin is for locating the advance on points type ignition, not needed on an 81.
Yes rough casting only machined where needed.
Not sure on the engraving.
 
You made me look
none of these have a heavy grind, engraving like yours,
Cam C is engraved "web" I suspect like yours it's a reground cam.
KIMG2898.JPG

But one is not like the others, why? :sneaky:
 
You made me look
none of these have a heavy grind, engraving like yours,
Cam C is engraved "web" I suspect like yours it's a reground cam.
View attachment 233456
But one is not like the others, why? :sneaky:

Interesting…didn’t think about it being reground, but I also know nothing about why or if it would even be worth it, but obviously it was to a previous owner. Thanks for pic to compare with!
 
Interesting…didn’t think about it being reground, but I also know nothing about why or if it would even be worth it, but obviously it was to a previous owner. Thanks for pic to compare with!
A quick check; the stock cams have a base circle of about 32.2mm +-.2mm, easy to measure with a caliper. The reground cam I have has a base circle of 30.2mm, or about 2mm smaller, so a quick caliper measure should tell you if it's a reground cam.
engraving on my cam;
web cam 59A.jpg


cam base circle.jpg
 
A quick check; the stock cams have a base circle of about 32.2mm +-.2mm, easy to measure with a caliper. The reground cam I have has a base circle of 30.2mm, or about 2mm smaller, so a quick caliper measure should tell you if it's a reground cam.
engraving on my cam;
View attachment 233473

View attachment 233474


Depending on exactly where I measure, it is right around 30 mm? Would that be OK? Also, I’m assuming it doesn’t change anything as far as rebuilding the engine?
 
Depending on exactly where I measure, it is right around 30 mm? Would that be OK? Also, I’m assuming it doesn’t change anything as far as rebuilding the engine?
So yes that's a reground cam, would be nice to see what that grind # means; race, street or somewhere in between.
From casual inspection, one appears to have completely different timing from the other three so I'm gonna to guess B is for a 270° motor?
Ding, ding, ding, eagle eye Raymond for the win! A 277 rephase, goes with that crank sitting on vee blocks in another thread.
447 cam specs;
XS650 cam lobe specs a.jpg
xs650 cam lobe duration.jpg
 

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So yes that's a reground cam, would be nice to see what that grind # means; race, street or somewhere in between.

Ding, ding, ding, eagle eye Raymond for the win! A 277 rephase, goes with that crank sitting on vee blocks in another thread.
447 cam specs;
View attachment 233482View attachment 233483
It gets dark early in Raymond's part of the world, more time to think.
 
Your cam would be no different in reality to a shell #1 , webcam 59a , megacycle 250-20 they all raise the lift by reducing the base circle, I expect you would get stronger bottom/mid range with an improved top end, if put it in check clearances including valve to valve, if you bought it second hand I expect its timed somewhere close to where it should be,
My unknown cam is still the best cam I've ever used.
 
Your cam would be no different in reality to a shell #1 , webcam 59a , megacycle 250-20 they all raise the lift by reducing the base circle, I expect you would get stronger bottom/mid range with an improved top end, if put it in check clearances including valve to valve, if you bought it second hand I expect its timed somewhere close to where it should be,
My unknown cam is still the best cam I've ever used.

Ok, awesome to hear!!!
 
I’m completely new to this but my understanding is that a reground camshaft is for enhancing performance, but could have consequences if you can’t adjust rockers….so would any of you know if I’m good to go or not so much?


Here’s the link I read through to come up with above questions…..

https://www.jalopyjournal.com/forum/threads/how-the-hell-does-regrinding-a-cam-work.36558/

You have an overhead cam engine with adjustable rockers - should be fine in that regard. Have you measured the lift as suggested above?
 
You have an overhead cam engine with adjustable rockers - should be fine in that regard. Have you measured the lift as suggested above?


No I haven’t. I’m waiting on camshaft bearings and oil seals. I’m going through the parts I have and making sure I’m heading in the right direction. I’m trying to ask questions prior, instead of after the fact and messing up an engine. I’ll definitely measure once I get to that point!
 
The dude I bought it from had some paperwork with a previous owners name on it and I was able to find the guy and got a response. He said,”The cam is a regrind unit from hoos racing. It's a shell #1 if my memory serves me right.”
 
Your cam would be no different in reality to a shell #1 , webcam 59a , megacycle 250-20 they all raise the lift by reducing the base circle, I expect you would get stronger bottom/mid range with an improved top end, if put it in check clearances including valve to valve, if you bought it second hand I expect its timed somewhere close to where it should be,
My unknown cam is still the best cam I've ever used.
Down South, that used to be called a "belly grind" cam.
 
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