I would like to share with you what I do on the side....
I live eat breath sleep shiz snowmobile clutch tuning and am now getting experience at building exhaust pipes.
My fave engine sound I've ever heard is the sound of a two stroke snowmobile engine.
These engines are one of the "meanest" sounding engines and produce painful db's for the human ear. Even with earmuffs, the sound is still loud, it just takes off the "cutting edge"
Heh.....at the end of the 600 dyno run, even the engine at idle sounds mean!
Here is some dyno runs we do on an "Inertia Dyno" The engine has to accelerate a 600 lb drum. It takes several seconds to grind out the dyno run and you'll notice at how much quicker that 985 pushes the dyno faster than the 600.
The dyno has a shaft which the connection is a clutch from a ZR1 Corvette and the means for braking, slowing down the drum is a brake caliper assembly from a ZR1 Corvette. Its about the only hardware that is reliable to hold back the capacity for 275 hp 1200 cc 3 cylinder rotax that my pal is building. The drum turns 2500 rpm when the engine is at 8500.
Here is a 985cc Rotax twin cylinder snowmobile engine making 203hp at 82~8300 rpms.
*If you click on a link you will only get to see one vid at a time.
*If you right click on the link and pick "Save Target As.." then you can save them to your hard drive.
*Once in your hard drive then you can open your media player and drag both of them into the player to watch the warmup...then dyno push.
http://www.dootalk.net/gallery/albums/album1643/1_warming_203hp_985.avi
http://www.dootalk.net/gallery/albums/album1643/2_dyno_203hp_985.avi
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Here is a 600cc Rotax twin cylinder snowmobile engine making 144hp at 8500 rpms.
This one we spend all day getting the pipes ready for fit in the chassis and then engine comes back out onto the dyno for final jetting....
Notice that the midrange rpms the engine starts to gurgle as it accelerates, at first we thought the PTO side mainjet was too fat and jet needles needed to be adjusted, however the float needle/seat rubber was worn and had to be replaced. Replaced it and the 600 ran as smooooooooth as the 985
...My camera batteries died for the final dyno push... ****, that run was super clean....about 144hp.
http://www.dootalk.net/gallery/albums/album1643/143hp_600.avi
The 800 twin rotax engine [182hp @ 8500 rpms] we build powers a snowmobile on pavement drags that can do the quarter mile in 9.91 seconds at 126 mph.
We have a 1000 triple in the 235hp range that pulls off mid 8 second 1/4 mile at 155+ mph.
[ November 23, 2005, 10:23 AM: Message edited by: Rev440 ]
