Predator 301cc 8hp stock timing

#1
Would anyone know what the stock timing is on HF predator 8hp engines (hemi head). Can't find it anywhere online. Would it be the same as a gx270? 20degrees? The cam I'm running is a 275 which needs 28 degrees timing. The 6627 flywheel has no timing advance. I just want to make sure I'm running correct timing and don't have the equipment or know how to check it myself with a degree wheel. I read on nr racing site to run a 4 degree key, I see where some use a 6. Not sure if i need it at all.
 
#2
Giving this a bump, never got a answer. I even called HF technical support and they are not provided any information by the manufacturer on specs for the motor.
 
#3
FYI I see these timing posts a lot and usually do not bother to even comment but The cam can affect timing to a very small degree because of intake closing affecting compression. However the main thing affecting timing is combustion efficiency and compression. The efficiency is controlled by the chamber (like fast burn vs bathtub or other design) Squish area and clearance to head at TDC and other factors. The more efficient the less timing required. Hemi Heads are generally slow burn as there is a lot of area and very little squish, and low compression. You should get yourself a degree wheel and pointer setup and also a piston stop to accurately set TDC. I would say that 28 degrees would be a perfectly safe timing.
 
#4
Giving this a bump, never got a answer. I even called HF technical support and they are not provided any information by the manufacturer on specs for the motor.
I agree with Ole. The only way to know for sure is with a degree wheel. I play with the small blocks, the crankshaft keyway is never in the same place. I've seen 18*-27* right outta the box. I don't even use crankshaft keys anymore.
 
#5
I just built a 301 a couple of months ago. Installed the ARC flywheel with a
4 degree advance key. Flywheel comes with NO built in advance. Pretty sure
lititure said it was at 24 degrees, same as stock.
 
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