When to go bigger on the T/C?

[LightningTeg]

Hey guys

Currently have a china 40 series on my Predator 420 setup. Since building it I've done some light upgrading.

Mikuni Carb
Air Filter
Exhaust
Governor removal

I plan on doing more down the road next year. Wondering when I should jump to a 94C converter? The 40 series are claimed @ 18hp. Im sure im there or above given how the gokart easily slides around with knobby tires on hard turns.

Havent seen to many 420s with that setup

 

[Kent]

Sounds like your probably at 18hp or very close. As far as upgrading the converter you could figure if it isn't broke don't fix it. First sign of losing any performance you can upgrade. What is your kart??? Do you have suspension and a setup you think is worth tricking out? Sometimes it's just fun to put the best parts on you can and you will be good with the 94C. Nothing wrong with that!!!

 

[LightningTeg]

Sounds like your probably at 18hp or very close. As far as upgrading the converter you could figure if it isn't broke don't fix it. First sign of losing any performance you can upgrade. What is your kart??? Do you have suspension and a setup you think is worth tricking out? Sometimes it's just fun to put the best parts on you can and you will be good with the 94C. Nothing wrong with that!!!

Old picture but you get the idea. Its fairly heavy, so it needs the torque.

 

[Kent]

Oh, that's nice.......... Would be nice to see a pic of it after the mods you've done. Looks like a good candidate for one of the "reverse" gear systems. That might be of more use to you at this point than the 94C. Does the 420 feel strong enough for your needs??? Did the mods you installed make a big difference in power???

 

[LightningTeg]

Oh, that's nice.......... Would be nice to see a pic of it after the mods you've done. Looks like a good candidate for one of the "reverse" gear systems. That might be of more use to you at this point than the 94C. Does the 420 feel strong enough for your needs??? Did the mods you installed make a big difference in power???

I will get some before I take it next week to go on vacation.

I have been heavily considering a reverse system! I dont know what would handle the power though? The only thing I can think of is taking something off of a snowmobile or ATV, like a chain case.

 

[Kent]

They sell the reverse unit that are pretty much designed for your application. Looks like holding up to your power shouldn't be a problem unless your really banging it hard while still rolling in the opposite direction. There is a lot of info on line dealing with installation of the box. Looks like you would probably need a welder unless you can see how to arrange supports and bolt them as needed. Here is a link of some guys doing an install, don't know if this is the best tutorial but is an example.

I like that you have the electric starter, that rocks!!! Did you build the kart?

 

[LightningTeg]

They sell the reverse unit that are pretty much designed for your application. Looks like holding up to your power shouldn't be a problem unless your really banging it hard while still rolling in the opposite direction. There is a lot of info on line dealing with installation of the box. Looks like you would probably need a welder unless you can see how to arrange supports and bolt them as needed. Here is a link of some guys doing an install, don't know if this is the best tutorial but is an example.

I like that you have the electric starter, that rocks!!! Did you build the kart?

Yeah my build log is here:

Spider carts Grand Daddy build

Hey everyone! New to forum, but I find myself here researching things often so figured I would start a build thread. Started this project 3 months ago. I've always wanted a go kart / off road buggy when I was a kid but my dad would never let me have one because he didn't want me tearing up the...

www.diygokarts.com

 

[Kent]

I read your build log. You defiantly have the skills and equipment to add reverse if you decide to. What is the O2 sensor for? Is it just for diagnosis or does it have some input to the engine?

I didn't realize you have to service the converter so often. Maybe the 94C would eliminate that need by being more robust for the power and weight of the kart. Just a thought when I look at your exhaust brace I wonder if it might brake off that cooling fin. I don't know much stress is created from the weight of the muffler.

 

[LightningTeg]

I read your build log. You defiantly have the skills and equipment to add reverse if you decide to. What is the O2 sensor for? Is it just for diagnosis or does it have some input to the engine?

I didn't realize you have to service the converter so often. Maybe the 94C would eliminate that need by being more robust for the power and weight of the kart. Just a thought when I look at your exhaust brace I wonder if it might brake off that cooling fin. I don't know much stress is created from the weight of the muffler.

I was using the O2 to tune the carb.

The exhaust brace helped but the muffler has still broke off a couple times LOL. I will be redoing it completely this weekend with some stainless pipe and a much shorter length.

 

[Joe-405]

About the time it gets a cam and/or a billet flywheel !