new member. 1st build. in need of experienced advice n tips

[LawnmowerMan918]

hello. first time I saw a racing mower, I had to have one. I had recently bought a perfectly good craftsman mower with a 20HP twin OHV Briggs&Stratton and started stripping it down.
being my 1st build, and really have no knowledge of "small engines" whatsoever, I have been at a standstill when it came time to do the drivetrain.
a guy said I'd need a 40 series torque converter. I did a tiny pulley swap by taking the belt from the original driver pulley to the 4 inch that powered the deck. wasn't impressed, so after much thought, I ordered a 12¼" drive pulley for the engine shaft. leaving the 3½" tuff torq pulley on the pumpkin. QUESTION: can I weld, or bolt being I have no welder, a plate in between the two to install the torque converter? I figured with the 12" pulley, the rpm would be 3 to 4 times greater, or climbs faster, resulting in a faster acceleration and more top speed. I could be totally wrong though. every engine I've seen, the torque converter is attached TO the engine shaft. don't know why.

 

[Denny]

Looks cool, but I have no idea how to gear one of those. No, do not weld anything to the engine shaft ever. You will wreck it. I think the 12.5 pulley is way too big though. Most tractors I have seen built have been built for off road and mud. Where crazy high speeds are not needed. Is your tractor a hydrostatic drive?

 

[LawnmowerMan918]

Looks cool, but I have no idea how to gear one of those. No, do not weld anything to the engine shaft ever. You will wreck it. I think the 12.5 pulley is way too big though. Most tractors I have seen built have been built for off road and mud. Where crazy high speeds are not needed. Is your tractor a hydrostatic drive?

yeah. it's the OEM "tuff torq" hydrostatic transmission of the craftsman mower

 

[LawnmowerMan918]

yeah. it's the OEM "tuff torq" hydrostatic transmission of the craftsman mower

I was told that I need to open the tranny housing n weld the spider gears to make it live axel/spool rear end. have yet to do

 

[Dingocat]

Pulley swapping that transmission won't help you go faster, it's just going to nuke the trans because you're spinning the pump inside too fast. Best bet is to go get a 5 or 6 speed trans from another mower.

 

[Dingocat]

Pulley swapping that transmission won't help you go faster, it's just going to nuke the trans because you're spinning the pump inside too fast. Best bet is to go get a 5 or 6 speed trans from another mower.

With a 6 in pulley on the engine, 2 on trans, a governer bypass and 21 in tires and I got to 50. WAY too fast for a mower with stock steering. Deathwish really.

 

[Budget GoKart]

i run a 4 on the rear and a 3 or so on front of my mud mower and its pretty fun to drive i want MORE speed though but next build is gonna be faster

 

[LawnmowerMan918]

With a 6 in pulley on the engine, 2 on trans, a governer bypass and 21 in tires and I got to 50. WAY too fast for a mower with stock steering. Deathwish really.

yeah, the steering wont be stock much longer. have a spindle kit in route to go with a tubular front end I'm fabbing up

 

[FlyFrog]

would a tourqe conerter work tho, i never thought about it for mine but i like the idea

 

[Denny]

would a tourqe conerter work tho, i never thought about it for mine but i like the idea

Why not? It’s got an engine. Only problem is it getting full of dirt and water which will kill it quickly.

 

[Budget GoKart]

drill holes in the very top of the pully where the bolt goes and clean it regularly it should be fine

 

[FlyFrog]

if i make a box around it with like a broom material at each end where the belt goes through to keep dirt off would it over heat and hurt the belt?

 

[Budget GoKart]

well if you add some kind of cooling i think it would be fine say like they would on race cars with an air duct and scoop mabye? but then again tcs on buggys have covers with just holes in them and are fine for long periods of time

 

[ONE-EYE]

I wouldn't do it. Seems like it would get WAY too wet, dirty, and hot. Not to mention, if anything drips down or spills on it or the belt...I'd look into other options first.