9v battery + xmods electrics?

[Ghost Rider]

I am building a 1/24 scale crawler. 5" wheelbase, it has super slick axles with SS steering servo mounted on the axle. 90 degrees articulation. stock super slick 1 links front and rear. cut up wally crawler tires. custom 2" travel shocks with ~3/8" uptravel. plate style chassis out of 1mm aluminum. total weight will be not much more than a regular super slick. Trans is my favorite part, it is a wally crawler motor and trans doubler with the super slick trans. it is VERY slow even with 9v juice. I may have to go to bigger tires it is so slow. Im sure as hell not making another doubler. the only problem is how the doubler is clocked. makes the COG kinda high so there is a lot of body roll.
I have 1/24 scout II and full size bronco bodies for it. pretty scale looking if a little tall.
so my questions:
I saw on here that xmods use propo electronics. would the electrics hold up to 9v power? I think the motor will, I ran a 9v on a wally crawler with no problems and this will have waaay more gear reduction. how would the run time be? I want at least 20 minutes out of a battery.
dont laugh that this setup sounds kinda ghetto, my goal was to build as small a crawler as I could for cheap, I have about $20 in it thus far.
I may go to hobby grade electronics If it is not too expensive. I am new to RC stuff so I dont know what all I will need. all electrics and battery need to fit in a 1.5"x.5x2" space. can anyone get me on the right track?
thanks,
Jeremy

 

[SVEN]

Do you have any pictures of you setup? I don't know of anyone who has done anything like that on here, so we probably won't be able to give you a good estimate of runtime.

 

[Ghost Rider]

I dont have a camera but I am trying to borrow one. with some bigger stickier tires it will be unstoppable. I just hope all that gear reduction doesnt grenade the axles.

I am just going to wire up the super slick electrics even though they suck balls. i need to see how the steering works. if it burns up then I will just get a real esc and stuff. this is pretty much learning for me.

does anyone have some input on electrics for such a confined space?

 

[bugman72]

I used to mod Xmods back in the day and unless you are running stacked FETs or an external FET board such as a "Whoa Nelly!" (see Xmodworld for description), then the most voltage you can run through a stock Xmod PCB is 8.4V. I've heard of a FEW folks that strapped a 9V to an Xmod and it ran like you-know-what for a couple of minutes, but then fried the stock FETS shortly after.

I ran a pair of 3.6V Lithium Ions in my Xmod and that is as much voltage as I would recommend. The Li-Ions charged at zero load to 8.4V total (4.2V each), but as soon as any load was applied the continuous voltage dropped to 7.2V (3.6V each).

If you gear the R/C right, you could probably get it to where the motor(s) aren't pulling any load to speak of, allowing you to run a lower MAh battery(s).