no theres no dyno data, ( dont know who can afford one ). but on SOME buggys the cvt set up ( rollers main spring ) MIGHT have to be tweaked to take full advantage of the cams.

I know my A12 cam in the GY6 produces peaks at lower RPMs and I can feel it top out faster than if I run the stock the cam, but I do not have specific data for it either. Didn't HeadMan do some dynomometer testing with the performance GY6 head? Did he ever publish the results? If he has access to a machine, maybe we could arrange to get some performance data on the CN cams.

Just wanted to follow-up on this -

I did a little more testing this weekend:

* Top end speed actually increased by 3 mph. I'm now running a consistent top end of 45mph on a flat gravel road

* I did a little hill climbing on a relatively small pond dam and it worked well, just not sure how well compared to the stock. I'm trying to decide if I want take Chuck's advice and take timed runs with both cams - that's a good two hours of shop time . . . hmmm.

One more question - I'm now running a 135 jet and even though my top speed has increased with this cam, I think there may be more. I know its important to check the plug, but how big is too big on these jets?

As long as your plug is not fouling or black, you're fine to keep increasing. So much has to do with the flow of your engine and the air density (elevation and temperature) that there is no uniform answer...

My CFMoto 250 runs a 138 and the Howhit 150 has a 140.

At some point your buggy will tell you it's to much. It will fall over it's self if the jets way to big. Good work brotherr. This is a low end cam correct? If so then 3mph on the top is a good sign as long as the low end is there

The best way to check jetting without equipment is accelerate to full throttle for appx. 6-900 feet, while holding pedal to the floor turn off ignition and stop your buggy. than pull your plug and read it . What you want to remember is not to let off full throttle until the engine stops, you do not want any idle time , just full throttle. Than after you read the plug if needed rejet until you reach a dark brown plug reading. I have the longer duration cam and I hope to have it installed by next week sometime, at which I will post an update. It will be going into a Coolster Challenger. We have been getting rain the last couple of days,as soon as it dries out I will be running stock taking notes so I have something to compare to. TOM

Cant wait

[quote="johnnyfazer"]In my continued quest for more low end power I decided to see what a performance cam might accomplish. I understand the basics of how a cam works (this link was really helpful to me - http://auto.howstuffworks.com/camshaft.htm). The way I understand it (and please correct me if I'm wrong), a cam with larger lobes should should provide more power - something we all want (insert Tim Allen grunt here).

To make a long story shorter - I put a new cam in from BigE. It took a little over an hour to install - this included rejetting the carb with a 135 jet and adjusting the valves. Then then it was off to my usual tests of timed runs of 0-100' and 0-200'. Although my times were shorter, I didn't see a great difference in the times. I guess the ideal test would be a dyno, but I don't have access to one of those.

What I did notice, purely by accident, was the fact that with the new cam in place, the buggy was really zipping out of corners much better - scratch that - the buggy is now wicked in the corners. I've ridden on our same flat dirt track for years, and until now the HH had never fishtailed out of the corners unless it was muddy - but now it seems I have a alot more low end power. I wasn't sure how much difference a new cam would make but I'm really impressed.


so far these cams have done well. I am happy with them. I will put them on sale stating thursday. It is an exchange program so I will need the old cams back. the sale price will be $165.00 and will run until the end of the month

HHHHHMMMM I think I see a winter project coming

I have the large cam and started running times and mph on the stock and than the new cam. Well I run into a problem at high rpm. Turns out the retainers were hitting the valve seals and after a long push to acheive top speed the retainer started hitting the valve guide . With the help of my friend Mike we had concluded that we needed to lower the valve guides to attain the proper clearance and find a better spring that would not coil bind which was another problem. Even with the stock cam the springs are near coil bind and only about .020" clearance between guide and retainer, and this hasn't been a problem but as we increase the lift and rpm this will become evident. I had talked to Tom from Kidnme and he was good to send me a performance head for his cost with large ports and titanium vave springs and retainers. MRP sells this head and would retail for somewhere around $275.00 to $300.00, don't waste the money, the clearance between the guide and retainer is larger but not large enough, the springs are still a problem with bind, and titaniun springs although lighter in weight and more expensive ,longevity of a titanium spring is short compared to a quality steel spring. Now I am waiting for the springs I ordered and I will be lowering the guides this weekend. When I complete the head I will fill you all in on the results.I have to add that when running the times with the stock cam, when I punched it from a dead stop it would shudder a bit,I attributed this to the hit clutch since I have the lightest pillow springs which cause it to grab and not slip, with the new cam however from a dead stop when punched the shudder went away and the wheels spun about a revolution and fish tailed the rear end. This was not on dirt but on rough ashphalt pavement. So to say the least the cam impressed me.So the large cam will require work to the head. TOM