I am thinking of putting a race cam into my 300EX. My goal is to produce more power. I am not interested in more speed. My questions are: Will this affect the reliablity of my machine? Will there be too much extra heat produced by this mod? Does it shorten valve life? What companies make the best products?
I want more acceleration out of the quad. Top speed is not needed.

Thanks for the help.

Chris "00" 300EX

 

Arctic Cat riders, avert your eyes! "Smart talk" follows!

Cstark said,

"I am thinking of putting a race cam into my 300EX. My goal is to produce more power. I am not interested in more speed. My questions are: Will this affect the reliablity of my machine?"

Yes, negatively, the degree depending upon how radical a cam you choose. Aftermarket cams typically produce higher valve lift from steeper ramp slopes, both characteristics increasing pressure and friction between the cam and rocker surfaces, stressing valve springs, and the valve spring keepers (ask those whose machines have "sucked" valves).

"Will there be too much extra heat produced by this mod?"

Perhaps not, if you do not "lug" the machine down, ride it in too high a gear at too low a speed, or engage in too many long, hard, slow pulls.

"Does it shorten valve life?"

Somewhat; there's a price to pay for the extra excursion, acceleration rate and velocity of the valve; some extra stress on the valve face/seat, the valve stem end, and the valve guide.

"What companies make the best products?"

There may be others, but WebCam (webcaminc.com) is a good 'un; one of the few single-cylinder engine cam grinders. WebCams are distributed by other businesses in kits named for the distributors, as well as directly from WebCam.

"I want more acceleration out of the quad. Top speed is not needed."

More acceleration comes from more power; "hot" cams raise the horsepower peak rpm, producing more power at higher rpms by permitting processing of additional fuel by increased valve lift, duration, and overlap. (You Arctic Cat riders still reading take a couple of ibuprofen tablets NOW; don't say I didn't warn you!) Typically a stock cam produces more power at lower rpm's than the hottie; however, at the top end, when the mill gets "up on the cam," look out!

Bottom line: Wringing more power out of a "cammed" engine comes only at higher rpm's; you must run faster or use a lower gear for this advantage. A hot cam isn't necessarily a good idea if lots of slow hard pulls are in your future.

For trail riding: I find the WebCam Grind 40a produces enough low-end punch yet permits some real screaming on top (Bayou 300). Doug Blackburn's identical setup (but with pipe) performs similarly.

I'd do it again; so would Doug, I think; you must decide yourself. Good luck!

Tree Farmer