SH Cams into a 1951 18s

Fiona69 · Post by **Fiona69** » Sun May 22, 2011 8:09 pm

Hello laxy from the very little I know under normal road going hair pin springs are fine but once extra load are put on them with higher lift cams etc they can be prone to breaking risking dropping valves. Once I recieve the kit I will let you know.

wilko · Post by **wilko** » Mon May 23, 2011 2:10 am

I've heard they use Chevy valves and springs, but don't know which model. Next time i have my head off will be doing the same. Most of the hairpins now have a wear ridge on them which mine did six years ago and i'm getting nervous waiting for a dropped valve!

wilko · Post by **wilko** » Mon May 23, 2011 2:12 am

By the way Fiona, "i" before "e" except after "c" !! But not always??

Fiona69 · Post by **Fiona69** » Mon May 23, 2011 3:01 am

Oh yes school was never a big interest of mine, bikes took a lot more of my time

Fiona69 · Post by **Fiona69** » Wed May 25, 2011 7:43 am

Has any one else any ideas on SH cam timing? Marty, the figures you have given make a duration of 308 degrees on the inlet and 159 degrees on exhaust, did you meen exh opens at 69 bbdc? this still leaves an uneven match of 308 inlet and 297 exh. Does anybody have the exact lift measurement for the SH profile?

Marty · Post by **Marty** » Wed May 25, 2011 11:10 am

My apologies, in- 59btdc, 69abdc ex- 69bbdc, 48atdc . As has been said many times, it is all in the archives, in this case http://archives.jampot.dk/Book/Workshop ... 7-1964.pdf
and go to page 8.
Marty

Fiona69 · Post by **Fiona69** » Wed May 25, 2011 10:30 pm

Thanks Marty I will be sure to search properly next time.
Andrew

msc · Post by **msc** » Sun May 29, 2011 7:43 pm

hi,i use sh cams in my 500 comp cs spec 52 matchy motor,and time it half inch before top dead,thats all you need to know.It also runs hair pin springs,i think they are better than coil as they cannot get bound,its thrashed hard regular,runs on castor oil,and a mk2 concentric carb.Super reliable with a hepolite 8.5.1 compression,you dont need fancy settings or new stuff,old is best,they knew how to do things proper back then. end of.........

Fiona69 · Post by **Fiona69** » Sun May 29, 2011 9:06 pm

Hi MSC thanks for the reply however what you have just discribed is your ignition timing and not your cam timing. My hairpin's were worn and I have read the pattern ones available now are prone to breaking.

msc · Post by **msc** » Sun May 29, 2011 9:50 pm

yeh,i didnt read it all, didnt realise you meant cam timing,sorry.As for the springs try to find some terrys ones,as per original fitment.A good used set is easily better quality than the new ones, they are s..t! there are loads around,and you may even find NOS on evilbay.