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mrbobian
06-13-2007, 10:15 AM
Ok, so i am in the middle of fixing an old BMW at this time and my dad and i were thinking about turbocharging it. This gets me thinking about turbos on lawnmowers. Does anyone do this? It makes perfect sense. In the car world, the down fall of the turbo is the fact that it loses it power at a certain rpm than regains it (usually at the apex of a turn causing a burst in power leading to wheel spin.) Anyways, since a mower is run at full rpm when mowing, it would make sense to get a couple extra hp from something like this. It is small and an intercooler would be easily placed. Any opinions?

tomo
06-13-2007, 10:44 AM
hello a designed engine 4 a turbo would be ok and some mowers in diesel already have them .

No turbo 4 my kohlers[air cooled] thanks now if i had 6x more head bolts , endless supply of head gaskets , oil cooler the size of a truck radiator ,engine bearings as there r none in a kohler vtwin ,decent con rods ,i am assuming u get the point ..

intercooler would need a electric fan and large altenator plus typically no room to mount it

A turbo of quality would probaly be worth more than a kohler 4 eg

tomo

nmurph
06-13-2007, 10:54 AM
why???????
the reason that turbos are used on cars is primarily to increase power with and eye toward fuel economy and packaging, neither of which is major concern with small engines. besides, they add cost, complexity, maintenance, and reliability issues to engines that are inexpensive, simple and rugged. when a manufacturer wants more power it is relatively easy to bore/stroke an existing design or just change the carburetor. just like what we used to do back in the ol' school days.
nice to dream, though.

lawnmaniac883
06-13-2007, 11:15 AM
Turbocharging a lawnmower would be more trouble than its worth. Mainly because you would have to have a turbo built for you as I strongly doubt theres an abundance of turbos small enough in production for use on a 900cc engine. Wouldnt need an intercooler but these engines are_not designed to be run with boost pressure, they would blow up in your face.

fargoboy
06-13-2007, 11:17 AM
good point Nmurph. I am always amazed at how manufactures have increased the hp's on mowers over the last 20 years. Remember Bobcat 48" with 8hp Briggs. Somehow they cut the same grass that you do today with a 32hp Kaw

Daneman
06-13-2007, 11:18 AM
Couple that with the fact that most guys don't idle down there machines, and let them sit at idle for a period to let the turbo cool down. Expensive part to replace when it gets damaged. And since it is about 100$ per hp to increase the size of a new engine, seems cost prohibitive to me. Just my opinion.

MarcSmith
06-13-2007, 11:19 AM
http://www.youtube.com/watch?v=GOaT7pECZCQ&NR=1
http://www.youtube.com/watch?v=6agXwQp-MWo&mode=related&search=
http://www.youtube.com/watch?v=YF0SCxIQ6PU&mode=related&search=

some one did it...:)

Idealtim
06-13-2007, 03:24 PM
Aw marc, you beat me to it..... I was thinking of those videos the entire time I was reading the thread.

mrbobian
06-13-2007, 05:34 PM
I realize that right now the addition of a turbo to a small engine is way too expensive and impractical, i was just thinking about manufactures building a small engine up to par to the demand of a turbo. Just trying to think outside of the box. One of my freinds made a makeshift turbo for a backpack blower. Plus, to answer the qestion why, in my case, my 19hp kaw is not enough for what i do but at the time i bought the machine, i did not know this. So what am i supposed to do? Pay $2000 to get a bigger engine or $7000 for a new machine...

pugs
06-13-2007, 06:11 PM
http://www.commercialpower.com/display/router.asp?DocID=80488

It would be cost prohibitive on a gas small engine. First you would probably want to step up to liquid cooled for a turbo engine to keep the heat in check. Second you would really want an EFI system to make it run correctly under all loads and conditions.

Finding a properly sized turbo could be a bit of a problem. They are turbo engines out there in the 500-1000cc range but they are not running at 3600 RPM max. They are probably running up to 6-10k RPM. So they are moving twice as much or more air through them already.

Pick up the book by Corky Bell if you want to read more about turbos ;)

mezammit
06-13-2007, 10:03 PM
Scag has a zero turn called the sabre tooth tiger with a turbo charged diesel engine on it. I heard that they are really expensive 14,000++ dollars.