Recently I acquired an all wheel steer mower that was beyond repair, however the rear steer transaxle was fully operational so I dropped it with the thought of putting it up front and making a 4x4 mud mower. At the moment the steering isn't hooked up but I've cut out a bracket that will wrap around the steering knuckle and allow it to steer. Based on what I've seen other people do, this is a first and requires no modification of the original steering linkage. I plan to upgrade the opposed twin motor a little(alot) meaning billet flywheel & connecting rods as well as equipping 2x 28mm flat slide mikuni to it, thinking of putting a amr 300 supercharger on it? any thoughts? (odviously id be geting rid of the transaxles when i hop up the motor)( this is update 1)
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4x4 lawn tractor is really cool, I actually had this same idea a couple months ago, why would you want to rip the axles out when you drop the built oppy in?
4x4 lawn tractor is really cool, I actually had this same idea a couple months ago, why would you want to rip the axles out when you drop the built oppy in?
because the transaxles are only rated for around 35 hp and this will be making around 50ish hp
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Age : 45 Join date : 2019-07-02 Points : 4473 Posts : 2385 Location : Ontario, Canada
Sounds like a good build plan and I like your idea of making a wrap around steering linkage, I hope it works out as planned!
It's not just about how much power you have, it's how you use it... guys blow up stronger diffs than those with only 10-12hp! Lol. What in the heck are you going to do with 50hp on a mower that you can't do with 25 for a tenth of the price? I bet it would cost upwards if 5 grand to build that to have it hold together and by then there's no original engine left anyhow except for maybe valve covers and engine tins...
4x4 lawn tractor is really cool, I actually had this same idea a couple months ago, why would you want to rip the axles out when you drop the built oppy in?
because the transaxles are only rated for around 35 hp and this will be making around 50ish hp
, meh, who care honestly, just don't pull to many wheelies, what would be the weakest links of those axles? Would there be a way to make them better?
4x4 lawn tractor is really cool, I actually had this same idea a couple months ago, why would you want to rip the axles out when you drop the built oppy in?
because the transaxles are only rated for around 35 hp and this will be making around 50ish hp
, meh, who care honestly, just don't pull to many wheelies, what would be the weakest links of those axles? Would there be a way to make them better?
Not that i know, and the weakest point would be the actual gears you'd shift in and out of the gears eventually just strip there teeth off with that many ponies
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Are you planning on keeping the 4WD parts and just taking out the trans axles after modding the engine?
How much does it cost to hop up an opposed twin engine? I'm just curious.
From what i have preordered at the moment around 1300$ but im also supercharging it so 250$ comes from that, otherwise its the stainless valves, billet rods and flywheel, reinforced shaved heads, hotter plugs, and the 2x 28mm Mikuni flatside carbs. On top of that im having the block reinforced and thats around 300$ so for what im doing it’s expensive but if you wanted to ad the bare minimum to rev to 5 grand it may cost around 800$
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To answer some unanswered questions/statements here. The amount of power is not what kills your trans… like Brainator said, it’s what you use it for. In my own words I would say more like how you drive it. If you’re speeding through the woods and catching air and landing hard you’re bound to split your diff whether it’s locked or not. Only thing that would help that is braces. The other thing is not so much the teeth on the gears as it is the shift keys. They just are not going to hold up to that kind of power. Even 25 HP is pushing it. I’m sure there’s ways to make it work and keep it more ‘original’ like I would do and use the transaxles, but it’s his build and probably less complicated and more reliable the way he’s planning on doing it even though he hasn’t mentioned it yet.
@Brainator, yes 50 HP is a lot and he could probably do just as much with 35. But there is no way it will cost $5k. $2500 may be more realistic unless he just has a wad of cash burning a hole in his pocket and feels like doing anything and everything he can to it. And oppys really can handle a LOT of power. Yeah he’ll need all new internals just as any other engine would need, but the block can probably handle a good 50 HP. Don’t know about the crank but even to push 30 you usually will need all new internals.
Sorry if that comes across rude to anyone in anyway lol it’s not meant to be. Just felt the need to clear some things up.
And ya got a nice start there man! I eventually plan on doing a 4x4 with a built motor myself but I aint up to it yet. Definitely will be watching this one!
To answer some unanswered questions/statements here. The amount of power is not what kills your trans… like Brainator said, it’s what you use it for. In my own words I would say more like how you drive it. If you’re speeding through the woods and catching air and landing hard you’re bound to split your diff whether it’s locked or not. Only thing that would help that is braces. The other thing is not so much the teeth on the gears as it is the shift keys. They just are not going to hold up to that kind of power. Even 25 HP is pushing it. I’m sure there’s ways to make it work and keep it more ‘original’ like I would do and use the transaxles, but it’s his build and probably less complicated and more reliable the way he’s planning on doing it even though he hasn’t mentioned it yet.
@Brainator, yes 50 HP is a lot and he could probably do just as much with 35. But there is no way it will cost $5k. $2500 may be more realistic unless he just has a wad of cash burning a hole in his pocket and feels like doing anything and everything he can to it. And oppys really can handle a LOT of power. Yeah he’ll need all new internals just as any other engine would need, but the block can probably handle a good 50 HP. Don’t know about the crank but even to push 30 you usually will need all new internals.
Sorry if that comes across rude to anyone in anyway lol it’s not meant to be. Just felt the need to clear some things up.
And ya got a nice start there man! I eventually plan on doing a 4x4 with a built motor myself but I aint up to it yet. Definitely will be watching this one!
You are absolutely right, it's his build, honestly his choice I was just curious as to why you want to drop the axles, makes a little more sense to me now, I personally on weigh about >130 lbs so breaking axles is no worry of mine, however, the trans I destroyed was done when I tried to remove the rusted pulley without pulling the trans, used a torch and a pickle fork, destroyed the C-clip on the input shaft, and the gear being wedged against the case put a hole in it.
To answer some unanswered questions/statements here. The amount of power is not what kills your trans… like Brainator said, it’s what you use it for. In my own words I would say more like how you drive it. If you’re speeding through the woods and catching air and landing hard you’re bound to split your diff whether it’s locked or not. Only thing that would help that is braces. The other thing is not so much the teeth on the gears as it is the shift keys. They just are not going to hold up to that kind of power. Even 25 HP is pushing it. I’m sure there’s ways to make it work and keep it more ‘original’ like I would do and use the transaxles, but it’s his build and probably less complicated and more reliable the way he’s planning on doing it even though he hasn’t mentioned it yet.
@Brainator, yes 50 HP is a lot and he could probably do just as much with 35. But there is no way it will cost $5k. $2500 may be more realistic unless he just has a wad of cash burning a hole in his pocket and feels like doing anything and everything he can to it. And oppys really can handle a LOT of power. Yeah he’ll need all new internals just as any other engine would need, but the block can probably handle a good 50 HP. Don’t know about the crank but even to push 30 you usually will need all new internals.
Sorry if that comes across rude to anyone in anyway lol it’s not meant to be. Just felt the need to clear some things up.
And ya got a nice start there man! I eventually plan on doing a 4x4 with a built motor myself but I aint up to it yet. Definitely will be watching this one!
yea thanks, you definitely did a better job at explaining that than i did i don't plan to drive it that hard (no jumps or speeding in the woods) the transaxles are just meant to be temporary whether they break or not is another story. for people wondering i'm setting it up so powerful at the moment because if this tractor ever outlives its use (major breakage) i want to be able to either turn this engine into a horizontal shaft or take the parts off of this engine in the pic and put them on a horizontal shaft briggs oppy then stick it on a future kart project. But most likely I would just fix any major breakage. About the cost this is what i have at the moment this is what i have going into it, -billet flywheel & billet rods:$708.03 - Blue Fuel line, fuel shut off valve, brass y nipple, 2x Mikuni 28mm flat slide, 2x Blue 45mm air filter, Adapter rubber Inlet Intake, extra cam (Just in case),Splitter throttle cable: $232.59 -misc.(such as pipe for headers, intake,fuel filter, induction tubing,hotter plugs, etc):$304.78 - idk if im doing a supercharger or not but this is the cost: $256.68 -So in total without the supercharger i'd be putting $1245.40 give or take -With the supercharger it would cost: $1502.08 Most likely the supper charger wont go be put on unless i decide otherwise after i've built this, However that being said where i live they do have a annual mud mower race, well hasn't been going scence corvid hit but they have announced they will be starting it back up next year around september or october so i have about a year to get this done lol. And if anybody wonders why I'd spend this much money on it, my reason is 5 words… For the hell of it
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Well we all do stuff for the hell of it so have at er! Lol.
What about the crankshaft? I'd be surprised if a stock one could handle much more than double the power plus the added compression and same for the pistons, to run 50hp you'll have to run alky or ethanol no? Whatever you do please, PLEASE build one hellava scatter shield and a firewall! Even at stock and just above stock power things can go bad FAST! At the power levels you're talking about you could end up with a giant frag grenade!
With that said.. I'm excited to see it built, don't think I'm hating on you! Lol
Well we all do stuff for the hell of it so have at er! Lol.
What about the crankshaft? I'd be surprised if a stock one could handle much more than double the power plus the added compression and same for the pistons, to run 50hp you'll have to run alky or ethanol no? Whatever you do please, PLEASE build one hellava scatter shield and a firewall! Even at stock and just above stock power things can go bad FAST! At the power levels you're talking about you could end up with a giant frag grenade!
With that said.. I'm excited to see it built, don't think I'm hating on you! Lol
That i know, the crank should be able to hold up to the hp its not hollow like most b&s engines, i've dealt with hopping up predator 670cc engines before on my buddys cart and they are able to take that much power with the stock crank, in fact the cranks are almost identical if it wasn't for the fact that b&s ballences the cranks way better than predator that and the fact that one is for a v twin as opposed to an opposed lol. 50hp isnt that much of a strech if you think about it, im removing the govonor and safely doing this by adding the billet parts requred, and pumping way more fule mixture into the engine with the x2 28mm mikuni to the whole ordeal. i do plan on making some reinforcements to the fire wall (just in case as when hopping up any engine) and because the stock hood wont fit on for the life of it i'll be beefing it up also by adding a custom hood if this, ALSO almost forgot i found a horizontal shaft oppy on craigslist the other day for 50$ and went and got it this morning, downside is it's a generator but i can separate the block from the generator so if i ever want to do a conversion it will be possible with relative ease. and i dont think that people are haiting they are just expressing their concerns which actually helps me alot so thanks!
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I am going to enter my 4x4 mud mower build, and i know ive already posted on it in a normal topic but id like to enter it into the competition, i started before i entered but i did not start it until about a month ago so i believe im in the safe zone, that being said this is what i plan to do: finish installing the rear steer craftsman rear end into the front end of the lt 1000, link it to the stock steering, make independent shifting for each transaxle, put ag tred mudding tires on both ends, make the gearing 1:1, fabricate skid plates for the transaxles, hop up the briggs and Stratton opposed twin and equip it with: arc billet aluminum flywheel and connecting rods, equipping 2x 28mm mikuni carburetors, adding copper gaskets to head and exhaust, straight piping it, possibly super charging it. Other things ill do to the mower include: fabricating a custom hood or expansion on the old hood, adding some light bars, repaint to a metallic blue and black color scheme and adding stiffness to the frame as well as fabricating a bumper. I will post updates as they come onto the forum as well as my YouTube channel. sorry it took a while to get the image got a little busy and forgot about it.
Last edited by JittyJat on May 4th 2023, 10:31 pm; edited 2 times in total
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After some thought I'm not going to be supercharging it as I would have to add an intercooler and other various safety measures that would cost me an additional 900$. However that being said it will still have the dual carb setup and other performance goodies. I also purchased some 3” pulleys for the front and rear transaxle then quickly realized after i got home that they would cause some serious belt slipping issues, so next time i'm back in town i'll be returning them and seeing if i can get some 6” pulleys then i will do the “holly pulley” mod to them. I have also decided that ill run kenda bearclaws on the mower (thanks to RCG video he posted about them)
Sorry its been so long had to wait for parts to arrive. That being said all of the stage one parts have shown up, basically just stuff to make it a mud mower. Ive decided to do 1 to 1 pulley ratio with the pulleys being 6 in all the way around. Earlier this morning i did the holly pulley mod to them and went with 8, 1/4 holes on each side of each pulley. I made a little jig to hole the face of the pulley straight while i drilled away.
sorry its been a while scence the last update life gets buissy ya know, anyways ive pulled the transaxle and got her all locked up did the holey pully mod, incase anyone is wondering how i got the origanal pully off i used a little bit of heat (propane torch) and a punch
got all the wiring done, unfortunately the previous owner buchured the old wiring so I've completely rewired it and chose to wire in a fuse panel so everything is on its own circuit, in addition to that I've also chose to run the gen 1 craftsman wiring as that's what connects into the motor and i like the ignition switch better, and I've left one of the safety switches in the wiring as now its hooked up to the break light so I have a functional brake light.
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