422 engine

[BobRip]

Change compression ratio and new carburator?

 

[Beechwood]

Wow; I just came home to grab some lunch before I head back to the job site and checked how this thread is going. Bob you are getting very close, but the 18,20, and 22HP engines already have the same compression ratio. You are half right so far. You might be the Grand prize winner !, to receive one of my " Grumpy Old Bastard Coffee Mugs " I'll check back later.

Beechwood
PS. How do you guys add the smiley faces?

 

[DHS]

On some motors with the same displacement they change the carburator and with some boat motors they increase the top rpm to increase HP.

Dale

 

[KMA]

PS. How do you guys add the smiley faces?

If you use the "Post Reply" button (versus the "Quick Reply") there are some Smilies on the right you can click on to add into the text of your post. When using "Quick Reply", you'll need to remember the character combinations. For example (illustration only, you must remove any spaces between characters):

= : o
= : )
= : (
= : confused :
= : mad :
= : p
= ; )
= : D
= : rolleyes :
= : cool :
= : eek :

Hope that makes sense.

So... do we need to buy the same carb that's on the 25HP model then?

 

[Beechwood]

Kevin;
The 22HP engine shares the same carb intake manifold as the 64 & 63 but the 25HP bore, stroke, compression rato, and displacement is different. The 25 has a block mounted oil cooler and a different governor spring set so I'm not sure how the larger mm carb would work on the 22HP engines.
I am going to install the 22HP carb on my 180 and adjust the throttle stop as bob stated and adjust the governor spring locations. You guys still haven't figured out my other planned change yet. Go back to one of my earlier replys ,( riddle/hint ).

 

[BobRip]

I would change the cam shaft if I were you.

 

[J_J]

Kevin;
The 22HP engine shares the same crab intake manifold as the 64 & 63 but the HP bore, stroke, compression rato, and displacement is different. The 25 has a block mounted oil cooler and a different governor spring set so I'm not sure how the larger mm carb would work on the 22HP engines.
I am going to install the 22HP carb on my 180 and adjust the throttle stop as bob stated and adjust the governor spring locations. You guys still haven't figured out my other planned change yet. Go back to one of my earlier replys ,( riddle/hint ).

Well, you could use Aviation gas, a roots blower and add a nitro bottle for those hair raising hill climbing escapades.

Why not change it out for a 25 hp Kohler?

 

[Beechwood]

JJ;
So far the only difference I can see in the owners manual and parts manuals for the 18hp, 20hp, and 22hp engines is the carburetor and governor settings. At one time I had thought about up grading to the 22hp engine, but if all it takes is changing out the carb, adjusting the governor settings, and adding dual exhaust I'll go that route. It will be a lot cheaper money wise and easer to add some HP.

 

[J_J]

JJ;
So far the only difference I can see in the owners manual and parts manuals for the 18hp, 20hp, and 22hp engines is the carburetor and governor settings. At one time I had thought about up grading to the 22hp engine, but if all it takes is changing out the carb, adjusting the governor settings, and adding dual exhaust I'll go that route. It will be a lot cheaper money wise and easer to add some HP.

You are probably right, that is just about the way the older Harleys did to improve that engine. larger carb, and straight exhaust.

 

[Beechwood]

JJ ;
One of the 3 motocross bikes I used to own was a Harley 175, believe it or not. They only produced them for a couple of years, I did a lot of engine work on that bike , I changed out the 27mm square valve carb with a 34mm Mikuni ( if my memory is correct )and reed valve induction.Then I added a 6" power bellow exhaust, changed the eng. and wheel sprocket gears, and bored & relined the jug. I had to add a compression release just to kick start the micro beast, but that compression release was great for flat track racing- I never needed to use the brakes going into a corner.