Gokart engine at 12,000 feet?!

[supermanotorious]

Ok, so I'm asking on behalf of a winch that will be built for a famous ski resort. But we use the same motors so this discussion could certainly benefit any of us wanting to race our karts up (let's say) Pike's Peak...! Is it as simple as the main jet? This will be a 420cc Predator. Step down quite a few notches from the #90? Or should I also look into a turbocharger or some other way of jamming O2 in the carb?

 

[Bbqjoe]

I'm pretty sure a jet is the place to start.

I bought a boat in CO. that was from OK. Ran like carp in CO. Took it to MN, and it was a whole new boat.
Yeah, I'd start with the jets.

 

[itsid]

hmm.. tricky ..

So leaned out jets (to accomodate for less oxygen due to less air pressure)
will rob about 35% of the engine power I'd say .. if that's still enough
(or better say more than enough )
to power the winch; then that's the way to go IMHO,
simply to keep the parts and maintenance costs down to acceptable levels.

Least restrictive air filters and intake in general assumed, it might be the best bet.

If the 420 does NOT provide the power you'll need to power the winch (considering 35% powerloss)
then I'd opt for a compressor instead of a turbo,
mainly to have a likely better control over air pressure,
and still a little easier maintenance compared to a turbo charged system.
(those tiny AMR300 or something maybe)

but frankly.. never done something alike, never seen something alike being done yet...
So.... nothing but a guess.

'sid

 

[supermanotorious]

awesome guys, thank you! keep the suggestions coming. I have some time to design and fab this build. they're hosting me in December to demo a winch so I'll need to outfit my own machine to run up there

 

[chancer]

Are there any 10,000 foot Plus mountains in AZ. where you could go to test?

 

[Bbqjoe]

He could probably go up to Flagstaff. Don't know the elevation.

 

[itsid]

A restrictor plate on the carb (dialed in which will be tricky perhaps)
or a large enough plastic container strapped to the intake with a small vacuum pump should
emulate high altitudes rather conveniently in the shop, not?

'sid

 

[bob58o]

Bury the intake in the snow.

These engines stay stationary right?
Cold air intake?
Does change in temp make up for difference in pressure?

Ideal gas law, who knew you'd be important later in life?

 

[Kartorbust]

He could probably go up to Flagstaff. Don't know the elevation.

12000 feet plus change at Humphreys Peak.

A designer knows he has achieved perfection, not when there is nothing left to add, but when there is nothing left to take away.

 

[CoroTheCat]

Are there any 10,000 foot Plus mountains in AZ. where you could go to test?

He could probably climb freerunners ego and test it there

 

[Poboy kartman]

He could probably climb freerunners ego and test it there

But to do that....the engine couldn't run regular timing.....it would have to be extremely retarded.

 

[Flyinhillbilly]

I keep thinking about mailing FR a gallon of 100% nitro to see the results, but I just can't bring myself to waste $60 worth of fuel.

 

[Kartorbust]

I keep thinking about mailing FR a gallon of 100% nitro to see the results, but I just can't bring myself to waste $60 worth of fuel.

$60 for 100%??? Jeez, I spent that much for a gallon of 20% nitromethane for my R/C I had.

A designer knows he has achieved perfection, not when there is nothing left to add, but when there is nothing left to take away.

 

[bob58o]

Step down quite a few notches from the #90? Or should I also look into a turbocharger or some other way of jamming O2 in the carb?

I keep thinking about mailing FR a gallon of 100% nitro to see the results, but I just can't bring myself to waste $60 worth of fuel.

Ship to Arizona or Colorado and problem solved?

You guys don't see how helpful FR is.

More oxygen via FR and Chemicals.

 

[bob58o]

Or buy some of this NITRO PROPANE from that kid's Uncle? LOL

https://www.rockymountainatvmc.com/p/936/12280/Klotz-Nitro-Power-Additive
Details
Nitro is an oxygenating power additive designed to exact the maximum level of horsepower from stock and modified engines.
Improves throttle response and acceleration.
Contains 50% Nitro propane and 50% Koolinal as a blending and cooling agent.
Blends with gasoline and methanol alcohol.