Thanks Ralph,..I am trying hard to see where the difference is,..I mean aside from the shaft size. At first I thought MAYBE it was the shaft size that gives it more HP,..due to possibly more torque? But the numbers say otherwise. The only variance in the torque numbers is from a couple other sites that claim the GX630 delivers 35.2,..rather 35.6,..But Hondas own site shows them as the same. Even if they are that close,..they are basically the same at the increment.
The shaft size is about the only difference I can see,..I mean,.when I see the bore and stroke the same and compression the same and the torque and RPM,. the same weight, same ignition, same air cleaner etc, etc,...I am loosely assuming these engines are the same. I looked up the piston number for each and they are identical. Now,..I'm not a motor head,.but I can recognize like numbers all day long.
Here's the thing,..I want to go to 10 GPM with performance,..if the shaft size was the same I'd simply buy the Udor 10 GPM with gearbox and try it out,..but,..with them being different I don't want to buy the pump with the 1" gearbox and then not be able to simply buy the larger engine and swap it out. That's my dilemma. But,..now that I'm looking into this it's getting more interesting just to find out what actually makes them different in HP range?
I have no problem buying the larger engine,.but I already have the 630,.and at $1500 with the muffler for a new 690,.I want to know I'm gaining in performance.
I think the 630 660 690 are based off the same raw design,..if there is an actual HP difference it must be coming from a larger jetted carburetor or something to do with air intake? Otherwise I think they are the same?
Glad it's only December,Ha,Ha,..
Jeff