Center stack divider??

[mshultz]

This has me curious. Dad was talking with a fellow at a pull yesterday who runs an M/450 type engine, and he said that he gained 4hp on the dyno by adding a center divider down through his straight pipe. From the description the guy gave dad said it sounded like it stopped a few inches before the bottom. Been trying to wrap my small mind around how this would be beneficial - some sort of scavenging effect I"m assuming. Just curious if anyone has any thoughts on it. Seems like cheap HP if it really works.

 

[fastpuller]

drill small holes in divider 250. inch one/half apart. about 36 in a 18 inch long stack. this helped mine 8.75 hp

 

[Mike Bock]

i find that hard to believe, 8 horsepower i heard that a straight pipe over a muffler is hardly worth doing but every little bit helps ,just my 2 cents though

 

[Mike Bock]

i find that hard to believe, 8 horsepower i heard that a straight pipe over a muffler is hardly worth doing but every little bit helps ,just my 2 cents though

 

[740]

The holes you drill in the divider? Are they .250 in in diameter?

Thanks,

 

[Anonymous-0]

any idea how or why? and did you dyno your tractor at the same oil and coolant temps?