Upgrade hp mods needed for 1996 Max II

[Swampghost]

Hello everyone. Just bought a 96 Max II with 16hp Vanguard OHV V-Twin. Have been reading about 23 - 27hp engines going into Max II (new ones) Was wondering what mods might be necessary to install a 27hp Kohler or something similar into my 96. What problems might I encounter? Plan to use it for light wood hauling, hunting, and maybe install tracks and plow. Thanks for the help. I am impressed with this site.
Tom

[thebuggyman1]

The easiest upgrade is a 23hp briggs....it will bolt right in. Or go to a Bandolero motor which is a briggs modified for racing go-karts. Usually they are rated at 28-30 hp.

Other motors often require a different secondary clutch moving the belt farther inboard to allow for a bigger primary clutch. Exhausts and engine cooling are also problems in an enclosed engine compartment.

[Tomo]

HI
23hp briggs and a red spring in the secondary clutch [red spring promotes a lot of downshift which will unload engine and make it far more suitable for application ]

tomo

[Swampghost]

Thank you for the information. Seems as if the prudent thing to do is stick with a 23hp Vanguard. In a new 23hp Vanguard would ypu recommond doing any modifications to boost hp? I'm not looking to run any Indy 500, just have respectable hp for plowing with tracks or hauling firewood. Thanks.

[Swampghost]

Don't want to sound uninformed but I am, please excuse my lack of mechanical knowledge but what is a "red spring in the secondary clutch?" Realistically, I will have to pass this on to whoever will be working on my machine. Thanks.

[Nubs]

The 23hp Vanguard is a drop in deal and the best bang for the buck if your having someone else do the install. springs etc will come in time if at all, the springs change RPM's / speed and low end torque. keep it simple and build from there if You find the need

[Tomo]

HI
Have the secondary disassembled and install the red spring . The spring keeps u in a lower gear longer also . This pattern of gear change best suits highly loaded situations . Many people on 6x6 have tried this and have liked the result . Cheap to do and would try this prior to an engine change . The 23hp briggs would most commonly come with a 1 1/8 crank ,u will need a 1 inch crank version to suit existing clutches .[upgrading to a 1190 clutch to suit ,1 1/8 crank would be better in the long term but costly, your choice .]
tomo

[thebuggyman1]

HI
Have the secondary disassembled and install the red spring . The spring keeps u in a lower gear longer also . This pattern of gear change best suits highly loaded situations . Many people on 6x6 have tried this and have liked the result . Cheap to do and would try this prior to an engine change . The 23hp briggs would most commonly come with a 1 1/8 crank ,u will need a 1 inch crank version to suit existing clutches .[upgrading to a 1190 clutch to suit ,1 1/8 crank would be better in the long term but costly, your choice .]
tomo

The 1190/1195 clutch is taller than the stock 780 and will interfere with the tub on a maxII. That is why the secondary would need to be changed to the inverted style.
[IMG][/IMG]

Compare to this secondary
[IMG][/IMG]

Most Briggs 23's in the US have the 1" crank, but I suppose there are exceptions...be careful of what you buy.

Edit: I found more pictures that may help.
[IMG][/IMG]
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