I have a Dyno 94ss cam in my Briggs 5hp Flathead project. With a cheater racing cam like this, is it normal to get some blowing out the carb when trying to pull start it? I'm 95% sure I have the cam timing right, but no way to check now that the bearing is pressed on. Am I gonna have to get/build an electric race kart starter for this thing?
question for those with an agressive cam
- Thread starter newrider3
- Start date
- Status
vgk
New member
Yea my flatty did the same. Never did anything though. Hopefully some one who knows will chime in because I would like to know also. Good luck 
Kenny_McCormic
Kartless....
Try a new plug?
Russ2251
AZUSA:Powered by LAWN-BOY
I do not know about this cam specifically, but this what the "Easy-Spin" feature does and is normal with a stock cam. Goes away when running speed is reached.
Linksep
New member
It's a function of cam lobe design and timing, once you have the engine running and the air/fuel has velocity headed into the engine it won't be a problem. If you spin the engine with the head off you'll notice the valve isn't 100% closed when the piston has reversed it's travel and started the journey back to the top. It's designed like that because if the valve was 100% closed with the piston at BDC you'd have incomplete cylinder filling due to the valve starting to close while the piston still has lots of travel left on the intake stroke. With a race cam there's even more lobe timing there to improve breathing at high RPM (trade-off being loss of efficiency at low RPM).
Double-check your carb baseline settings, that's way more likely the cause of it not firing than valve timing.
Double-check your carb baseline settings, that's way more likely the cause of it not firing than valve timing.
- Status