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Hi guys,
Could use some help getting info.
Any links to how kowies get the high torque numbers is appreciated.
Thanks in advance.

Couldn't tell you how Kawasaki does it but generally it's done by mechanical efficiency... higher compression ratio, camshaft timing, cylinder head design, intake and exhaust design etc
Stroking...

LIke mike says. A company which understands air cooled (and water cooled) engines. An Intek V is what , 45 cu in producing 24 HP, Kawasaki can squeeze 90 HP out of that . To be fair, the tractor engines need torque, not HP so much. But the point is the Japanese understand the engines and are very good with metal and quality control. What is the torque figure?

motoman said:

LIke mike says. A company which understands air cooled (and water cooled) engines. An Intek V is what , 45 cu in producing 24 HP, Kawasaki can squeeze 90 HP out of that . To be fair, the tractor engines need torque, not HP so much. But the point is the Japanese understand the engines and are very good with metal and quality control. What is the torque figure?

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When you ask what is the torque figure, it's going to change depending on a number of factors like Mike88se said no two will be the same.

It's a trick they really do not put out more efficient torque.
Just because a engine has a higher torque rating does not mean that it is usable torque. The max hp and max torque should be obtained as close as. Possible to the same RPMs

If max hp is at 3600 RPMs and max torque is at 2200 RPMs then your losing too much torque at 3600 RPMs

Carscw said:

It's a trick they really do not put out more efficient torque.
Just because a engine has a higher torque rating does not mean that it is usable torque. The max hp and max torque should be obtained as close as. Possible to the same RPMs

If max hp is at 3600 RPMs and max torque is at 2200 RPMs then your losing too much torque at 3600 RPMs

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It's not a Trick. All mower engines are test the same way, doesn't matter who the manufacturer is. There all tested in accordance with SAE J1995, verified by TUV Rheinland Group, and certified by SAE International. Actual power and torque output will vary depending on numerous factors, including, the operating speed of the engine in its application, environmental conditions, maintenance, and other variables. You can get that on any of there sites.

What I am saying is what they say is max torque is not the torque you get to use.

This engine has 44.6 ft lbs of torque. Running the engine at 3600 RPMs it only has 36 ft lbs
The curve is to much for the engine to hold its RPMs at 3600 under a heavy load. But does allow it to recover fast.
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Carscw said:

What I am saying is what they say is max torque is not the torque you get to use.

This engine has 44.6 ft lbs of torque. Running the engine at 3600 RPMs it only has 36 ft lbs
The curve is to much for the engine to hold its RPMs at 3600 under a heavy load. But does allow it to recover fast.
ATTACH]20236[/ATTACH]

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I understand and agree. If the powerband... if the torque is not usable in the normal operating RPM range then it isn't useful. Still, I'd trust a Kawasaki to get closer to the usable torque than say.. Briggs. The Japanese have always been good about close tolerances, cam and intake design and such. It's why their engines will usually outlast and outperform most engines.

Mike88se said:

I understand and agree. If the powerband... if the torque is not usable in the normal operating RPM range then it isn't useful. Still, I'd trust a Kawasaki to get closer to the usable torque than say.. Briggs. The Japanese have always been good about close tolerances, cam and intake design and such. It's why their engines will usually outlast and outperform most engines.

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I agree the kawwi might out last a briggs. but most briggs deliver the torque closer to the operating RPMs

There are a few things you can do to get better performance out of any small engine. Adjust valves intake a little tight exhaust a little loose.

If you really want to get the max hp out of a mower engine use a offset key on the flywheel.

Carscw said:

I agree the kawwi might out last a briggs. but most briggs deliver the torque closer to the operating RPMs

There are a few things you can do to get better performance out of any small engine. Adjust valves intake a little tight exhaust a little loose.

If you really want to get the max hp out of a mower engine use a offset key on the flywheel.

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? Change the valve timing?

Mike88se said:

? Change the valve timing?

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It's a little bit like advancing the timing on a engine with a distributor.
Keeps the intake open longer.

I have a few friends that kart race and this is what they do in the stock class.

I came accross a site that hot rods mower engines. We all know what it takes. Seems like turning these ac engines faster would create a real time bomb, what with the weak rods and hot running. Besides, cutting grass with wheelies will not end up even.

motoman said:

I came accross a site that hot rods mower engines. We all know what it takes. Seems like turning these ac engines faster would create a real time bomb, what with the weak rods and hot running. Besides, cutting grass with wheelies will not end up even.

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Haha I agree I would leave the engine stock they all cut the grass. Unless your racing or pulling leave it alone

Carscw said:

It's a little bit like advancing the timing on a engine with a distributor.
Keeps the intake open longer.

I have a few friends that kart race and this is what they do in the stock class.

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That sounds like ignition timing. The other part sounded more like valve timing. I would want to hot rod any of my machines but there's almost always room for improvement on a factory engine. And just to be clear... improvement w/o sacrificing reliability or longevity.