820vs840 kit

Fox Run · 12-02-2009, 06:41 PM

Hi guys,
I'm having hunterworks build me a motor with the 820 fundy kit. My ? is what is the real difference in the 820 vs the 840, and how much hp does each have.

Junior · 12-02-2009, 06:50 PM

You should read some threads on these motors because you are about to open a big can of worms, I know both motors have alot more HP & torque than stock! I think you will still be happy with the 820 or 840.

Four Stroke Tech · 12-02-2009, 07:11 PM

There will be a little gain in torque but that is it. The main power gain will come from the cams if you are not running any ported heads.

Hunterworks · 12-02-2009, 07:47 PM

Quote:

Originally Posted by Four Stroke Tech

There will be a little gain in torque but that is it. The main power gain will come from the cams if you are not running any ported heads.

Best answer I have ever seen from FST.

Hunterworks · 12-02-2009, 07:48 PM

If all things being equal except for 820 versus 840 20cc's are not going to change anything you could feel. I engine dyno might could show you but your butt won't know it.

Fox Run · 12-03-2009, 03:54 AM

Well i guess my next ? is can i just put in a performance cam, and not do anything to the heads. And if i do need to do the heads how much$$$$$$

Hunterworks · 12-03-2009, 05:42 AM

Yes you can but in my experience head work only helps way up top.

Some would say all power in a CVT vehicle is high rpm power but from 0-20 while the belt is shifting out and the RPM is going up it is in the lower RPM range.

Only if I was doing constant top speed running would I do head work.

Four Stroke Tech · 12-03-2009, 07:16 AM

Quote:

Originally Posted by Hunterworks

Best answer I have ever seen from FST.

All my answers have been truthfull,you just didn't want to hear the truth sometimes.

Shan · 12-03-2009, 07:47 AM

Well seeing how I've done several 840's and did my teryx to an 820 simply because I had the pistons laying around I can say that there isn't much difference but if you're going to pay in full for a kit then why bother with the 820?

Four Stroke Tech · 12-03-2009, 08:01 AM

Quote:

Originally Posted by Shan

Well seeing how I've done several 840's and did my teryx to an 820 simply because I had the pistons laying around I can say that there isn't much difference but if you're going to pay in full for a kit then why bother with the 820?

The reason is his builder has a problem with hearing the truth from me so his customer will pay twice as much.

I PMed Fox before the sale,he didn't answer it he just sent the PM back blank.