Advancing cam timing

[robby12]

I have a stock 5hp Briggs or some what stock shaved head ported and polished shaved the eye brows billet rod stock carb and strait piped would Advancing cam timing a tooth or two help performance or hurt or maby retarding the timing any input guys

 

[mmisterbungl]

if you move the cam from any other position that it is in, your engine probably won't even start.

 

[mc73cromags]

Cam timing must be done with either offset keyways or an adjustable timing gear. Cam timing changes are usually made in small degree increments. Moving the timing a whole tooth in either direction would be too large of a change.

 

[robby12]

so what other little tricks and mods can i do because i want to squeeze every last bit of power out of this motor

 

[mr.modified]

You can Move a briggs 5hp flathead a tooth one way or another and it will run. In general, You don't want to advance or retard a cam more than about 8 degrees. Advancing a cam helps low end while sacrificing some high end. Retarding the cam helps high end while sacrificing low end. To find out how many degrees each tooth is on a perticular cam, Count the teeth on the cam and divide by 360. Briggs 5hp flathead cams are about 6.2 degrees per tooth if I remember correctly. I ran the cam in my go kart 5hp engine advanced one tooth. I can't say you will notice much difference but you can try it anyway, every little bit helps. As far as getting all you can out of that engine, you can run thinner oil, make sure everthing is carbon free for flow, plug gap set correctly, and make sure valve clearance is correct

 

[Ibanez616]

An old trick people used to do before aftermarket cams were available, was file off the easy spin, and twist the cam to advance or retard timing. Its a waste of time now though, with all the aftermarket cams you can get.

 

[65ShelbyClone]

To expand upon what mr.modified said, changing the cam timing just moves the torque peak around. Advancing it will shift the torque peak downward in RPM(at the expense of peak power) and retarding moves it upward(at the expense of peak torque). It's really just trading one for the other in either case.

If the engine is moderately built, then a $50 aftermarket cam is going to going to be worth far larger gains than anything that can be done with the stock profile.

 

[Dr.Soos]

i was told the samething but still advanced it two teeth and it runs it actually runs great gets up to rps real fast

 

[tim mclaughlin]

I have two nos horstman crank gears witch have three keyways. 2 deg. advanced, 2deg retard, or straight up. They are for the larger crank with the pin not the key. I'd sell one for $15.00.