747cc Kohler Command Pro efi engine differences

[2Channon]

I have been wondering what the differences are between the 23 hp, 25 hp, & 29 hp 747cc Kohler engines. Is it just the cams?

[jpswift1]

Good question, maybe the carburetors? I don't know about the Kohlers but the Briggs 14HP and 16HP Vanguards are the same (480cc displacement) except for the carbs and little removable restrictor rings they put in the exhaust ports of the heads.

[needcoffee]

Near as I can ascertain the 23 hp is a 694cc engine with a shorter stroke than the 747cc 25, 27, 29 hp engines. The new frontier has a 25 hp in it as per the serial number. Since I purchased one I have been browsing thru the Kohler manual. All specs and parts appear to be the same, including injectors. Since it is EFI i would guess the tune is different. The torque on all three 747cc units is almost the same. So I am debating chipping it. Not sure it is worth it. But I probably will anyway lol.

I am trying to figure out a way to mount an alternator on it though.

Hope this helps and if anyone has different info please add it. By no means am I an authority.

[Noel Woods]

I believe the above efi Kohler is the same engine. The tuning may be slightly different. I believe the actual engine size is around 747cc. It does have an on board diagnostics port which should allow for a reflash to the upper hp range if applicable, I believe however the engine is a rebadged version of the 29hp.

I doubt that any dealers will chime in on this due to obvious reasons.

[2Channon]

That's what I was thinking. You can bump that Argo Frontier to 29 hp. That's what I'm talking about.

[needcoffee]

Kohler Command PRO ECH730 V-Twin MAGNUM EVO-Tech Industrial Engine Performance Chip

This is the booster i am looking at

[Noel Woods]

Nice find, let us know when you get the unit installed and report on the performance.

[RandyNiesen]

If it's EFI, it doesn't have a carburetor. It does however have a throttle body, which is similar to a carb, except it doesn't have a needle/seat, or float bowl, only has a butterfly throttle valve to control how much air is being let into the intake manifold. That being said: when it comes to powering up or down on any fuel injected engine, changes to the cam can be made, but the biggest thing is the size of the injectors which it's using. Smaller injectors equal less power, larger injectors equal more power. If you upsize the injectors then you'll need someone to also get into your control module, and tell it what you've done, so it can make the necessary adjustments for the timing, and pulse length in miliseconds, ect. ect. It can be done, but you have to know what your doing, and/or get a smart tech to help you out with that. I've worked on fuel injection systems for many years, and they're not all that complicated to work with, just a bit confusing is all.

[needcoffee]

You are correct. In this case of the 747 cc Command Pro EFI engines. They all possess the same cam, injectors, etc... The only thing I have found to be different, as per the service manual, are the tune on the ECM and governer setup which are both easily rectified.

Now a byproduct of more power is heat. So climate is a consideration. I am running the hood fan which at 8.1 amps will necessitate an alternator (which I am doing anyway for auxilary power). That will do me. For more cooling you could remote mount the oil cooler with a thermistor controlled fan to get direct cooling. Or possibly into the cold air engine cooling air intake. That opens another can of worms.

Just some of my thoughts.

Regards,

Jeff

[needcoffee]

Added an alternator to my 2015 Frontier

Pics of my pulley, brackets, and alternator. Should have 80% output available at idle of the 40 amps possible. Had to remove the exhaust metal ducting and do some trimming and reinstall. Now I have the power to run the hood cooling fan and auxillaries.

Works well so far.

Regards,

Jeff

[esimon4]

Did anyone upgrade the chip in their 23 hp Kohler?

[Anywhere]

Did anyone upgrade the chip in their 23 hp Kohler?

Yes.

[Snow mogg]

I just bought a mini supercharger for my fathers Avenger as well as a much larger 41mm carb, i will try to update how it works out.

[Snow mogg]

I thought the 23/25 only came with a carb, what differences did you get with a new chip