Hello power help

Nightswatch

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Hello I have a B&S 724cc Intek vertical shaft engine, rated at 25hp.
serial; 13 1120 YG 38184
I am looking to gain more power / torque .
I use this rider mower for rough grass and areas we dont wish to abuse
our other mower on .
Do you have a cam / lifters / springs / intake that could help ?

Not looking to go nuts just ....more power

seems like all the parts are for 670cc or 212cc
thank you
 

sgkent

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if life could be so simple. HP is a function of RPM and Torque. To make more HP the engine needs to spin faster, which is death on many of these small engines because they weren't designed for it. Likewise more torque means burning more air and fuel at the same RPM so higher compression and efficiency, or a larger displacement are needed. You won't get there from here without spending some money to turn that into a racing engine, next will be the blade speed so you'll be changing pulleys, next will be the transmission can't handle the load and heat......... You bought a package. That is my two cents, and my history includes some serious racing engine design and building.

Best thing you can do is make sure that engine is kept in tip top shape. Same for blades, tires and belts etc.. Also avoid things that make the world seem to be stuck in slow like too much coffee before mowing - that will help speed things up too. :)
 
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bertsmobile1

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I see where you are coming from
Long term either fit a bigger engine or find a smaller deck.
Don't know what mower it is on but find the smallest deck that will fit, even if you need to cut one up and weld your lifting points on it
Most ride on mowers are about the same width between the chassis rails.
Genuine garden tractors are about 4" wider than lawn tractors where as BS garden tractors ( any Husqvarna & Most MTD's ) will be the same width .
Other than that most of the stand on loaders have a mower attachment that are fairly narrow and make really good rough cut mowers plus you end up with a universal digger, loader , sweeper, grader , tow motor , etc etc etc
Second hand Kangas & Dingos ( plus your own local brands ) are quite cheap and dead simple machines being that everything is run off the single hydro pump which is repairable at reasonable cost , particularly when compared to the units on the bigger ZTR's .
I have a couple in the repair run used by plumbers & bricklayers
 

Nightswatch

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I see where you are coming from
Long term either fit a bigger engine or find a smaller deck.
Don't know what mower it is on but find the smallest deck that will fit, even if you need to cut one up and weld your lifting points on it
Most ride on mowers are about the same width between the chassis rails.
Genuine garden tractors are about 4" wider than lawn tractors where as BS garden tractors ( any Husqvarna & Most MTD's ) will be the same width .
Other than that most of the stand on loaders have a mower attachment that are fairly narrow and make really good rough cut mowers plus you end up with a universal digger, loader , sweeper, grader , tow motor , etc etc etc
Second hand Kangas & Dingos ( plus your own local brands ) are quite cheap and dead simple machines being that everything is run off the single hydro pump which is repairable at reasonable cost , particularly when compared to the units on the bigger ZTR's .
I have a couple in the repair run used by plumbers & bricklayers
yeah its on a older mtd garden tractor ....hmmmm maybe i can wedge a 350cid in it
 

Nightswatch

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if life could be so simple. HP is a function of RPM and Torque. To make more HP the engine needs to spin faster, which is death on many of these small engines because they weren't designed for it. Likewise more torque means burning more air and fuel at the same RPM so higher compression and efficiency, or a larger displacement are needed. You won't get there from here without spending some money to turn that into a racing engine, next will be the blade speed so you'll be changing pulleys, next will be the transmission can't handle the load and heat......... You bought a package. That is my two cents, and my history includes some serious racing engine design and building.

Best thing you can do is make sure that engine is kept in tip top shape. Same for blades, tires and belts etc.. Also avoid things that make the world seem to be stuck in slow like too much coffee before mowing - that will help speed things up too. :)
yeah not worried about the fuel usage , i wonder what the real world hp is . Seems that older tractors had more power on less hp rating . might just put a small supercharger on it
 

StarTech

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That 25hp 2013 44S677-0003-G1 is already way more power than most mowers with a 38" decks need.

And according the Briggs it is on a 2691172-01 - Regent EX, 25 Gross HP B&S Hydro and 38" Mower Deck mower.

I am running a 21hp with 42" and I cut some very tall grass with it. It is so much power that I had to upgrade the deck belt from a 1/2" belt to a 5/8" belt as I was burning up the 1/2" belts.
 

bertsmobile1

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For rough cutting get low lift blades .
No mulchers and no Gators
And keep them sharp
A couple of file strokes can make a massive difference.
Down here we are allowed to use swing back blades so the local makers fit 5" to 9" long blades that are 1/8" thick on a big disc.
The disc stores a lot more momentum than a really heavy bar blade will and if the mower becomes overwhelmed the blades just swing back so cut a narrower swathe
Because the blades are thin to start with, even if the cutting edge is worn away the base blade is thinner than the cutting edge on most bar blades
Thus I can cut 5 acres of rough pasture faster with the 8hp 32" local mower than I can with a 19hp 42" USA mower using bar blades .
When the grass is very long or thick low lift blades ( some times called sand blades ) will power through the grass so much better than high life ( bagging ) blades or the 3 in one blade that universally does a poor job of mulching, throwing & bagging .
It is worth while to get several sets so you always have a sharp set ready to pop on and regular blade replacements will alert you to spindle bearing failures early .
A 2 minute job with a rattle gun & some truck ramps ( taller than car ones ) and of course having several sets means you can sharpen a couple of sets in the evening when it is too dark to mow .
I have commercial customers that swap blades between every job and they maintain that the sharp blades allows them to do 1 to 2 more lawns a day in peak season while naturally giving them a better cut.
It also alerts them to spindle problems so they can drop the mower off to me in the evening on their way home & pick it up in the morning ready to run with fresh bearings .
 

Tinkerer200

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." Seems that older tractors had more power on less hp rating ."

"Once upon a time", some engines such as Wisconsin and Kohler rated according to what you could expect hour after hour. Now they rate them in the lab using unusual condition and for what they can wring out of them for just a very, very short time. Actually, B&S engine owners manuals used to say that you could only expect about 80% hp of what the sticker said and that after break in and under idea conditions. I had a Wisconsin engine rated at 5 hp which could turn a "12.5 hp" B&S inside out.

Walt Conner
 

slomo

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yeah not worried about the fuel usage , i wonder what the real world hp is . Seems that older tractors had more power on less hp rating . might just put a small supercharger on it
At over 5 bucks a gallon in cheap Oklahoma, I bet you've changed your tune recently LOL. Don't know what you pay at the pump. Heard Kali is over $7.50 a gallon.
 
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