Yerfdog Spiderbox, Briggs 1550 help

[Buford_T_justice]

Has anyone had any experience with a Briggs 1550 snow series engine? I got one mounted on a Spiderbox. With a 7:1 gear ratio it has great low end torque. The 1550 stands for 15.5 ft pounds of torque, so it's got plenty of power to move the cart around. However the max RPM is really lacking, even with the governor bypassed.
One thing I've noticed is the stock carb is tiny for the size of the engine. Anyone know of a mikuni 28mm carb or similar carb would work, combined with a header and better air intake?
Seems to be a great engine to build off of but can't find anything about building them online. Any advice would be great.

 

[Karttekk]

Those are robust engines with their cast iron sleeves. They're built for moving heavy snow around, that's why there's plenty of torque. They aren't built for high RPM's, designed more for heavy workloads. Maybe consider one of their racing engines?

https://www.briggsandstratton.com/na/en_us/products/engines/racing-engines.html

 

[Buford_T_justice]

I would prefer to keep this engine if at all possible. If I do decided to go another route, a predator 420 would definitely be my 1st choice. I think before I give up on the 1550 I will try messing around with a much larger mikuni carb and some different jets. The torque is impressive, would hate not to use the engine.

 

[JTSpeedDemon]

Remove the governor. Doing that will free up your wanted RPMs to about 5200 RPM, and if you're going to be putting a Mikuni on it anyway, that would completely bypass the governor.
And since it's possible to blow up your engine by just bypassing the gov, it's best to remove it completely.

 

[Buford_T_justice]

Had some fun on the kart today. Not much for top end speed, 30 mph maybe, but man it's got some torque. Especially with using a knock off 30 series. Will do donuts on dry payment pretty easily which surprised me.

An eBay special mikuni 34mm round slide will be arriving Wednesday. Next weekend I'll hook it up with a uni air filter and header and see how the Briggs responds. Will be an experiment, could be a too big of a carb.

On another note, my neighbor is selling a sled, specifically a 89 Yamaha Exciter 570 dirt cheap. Steering it shot, plastic all torn up but the engine/clutch apear to be in working order. Anyone here have experience with this engine? I imagine it would rip. Thinking about going that direction instead.

 

[Buford_T_justice]

Got the mikuni 34 mm carb mounted with some a Home Depot plumbing section special custom intake lol. I was skeptical that it would even work, or at least that Jets would be way off. First real pull after it was mounted it fired right up. Couldn't believe it. Took it for a quick ride, and it turned the kart into a whole new beast. I was able to hit 40 mph which was about as fast I want to go. Mind you this is with the stock exhaust which I'm sure is quite restrictive.

Does anyone know if there are any performance parts for this engine out there. Like heavier springs, rods, etc. I can't find anything online.

 

[Buford_T_justice]

Old carb vs new
Home Depot intake.

 

[Bansil]

Hory carp dat is biggly!!!!!

 

[Buford_T_justice]

More pictures. Hooked up a new throttle cable today and wired some fog lights up.

 

[Buford_T_justice]

Has anyone used this clutch before? 30 series 'juggernaut".
https://www.gopowersports.com/super...OI_H7qAwyizmjS55Ezuiui-0wKG1IOrxoCSJsQAvD_BwE

Is so, worth the price? Comparable to the 40 series?

 

[landuse]

Has anyone used this clutch before? 30 series 'juggernaut".
https://www.gopowersports.com/super...OI_H7qAwyizmjS55Ezuiui-0wKG1IOrxoCSJsQAvD_BwE

Is so, worth the price? Comparable to the 40 series?

I have heard that it isn't all that it is made out to be. Don't get me wrong, it is definitely good, but it isn't going to be the solution for everything. And at the price.....

 

[Wilson_Engine_Shop]

I tried the Juggernaut on my Murray Explorer with a stage 1 kit, 18lb springs and no governor. It shot out of the hole like it never had before! But... it cut my speed from 40+ mph at 5k to only 12 mph at 5,500 rpms. Needless to say I was severly disappointed

 

[J.S.@SMS]

You've done some work to this thing. But I don't think it'll ever catch that Trans Am SD. But that carb should be plenty for that engine.

 

[Buford_T_justice]

Thanks for the info. Sounds like I'll pass on the Juggernaut clutch. Honestly I'm pretty pleased with the 30 series. I'll keep put with that and maybe mess around with some gearing. I have sprockets to gear it all the way to 9.5:1. Really curious to try that out and see what it's like. The take off is already pretty sweet at 7:1.
Rims and hubs arrived today for the front end. Upgrading to 8 inch rims so I can run some 20ish inch tires up front. Kart looks silly to me with how big it is with only 15 inch tires in the front.