100,112,115HP differances???

[Boilermaker]

What are the differances between Johnny-Rude 100HP, 112SPL, 115HP old(when they where messured at the flywheel), 115HP (newwer) .<br />Are these all the same displacement/block???<br />Is the port timing different, the Induction/Exhust bigger-smaller? OR is this alot of marketing hype & working with power output tolerances (+/-10% would cover most of these)???<br />I was wondering if some of the parts from the higher output engines could be swapped onto my '78 115HP to get a little more top end???<br />Thanks<br />

 

[Dhadley]

Re: 100,112,115HP differances???

The 100 has the same port timing of the 90. All the "bubble back" v4 crossflows (110, 112, 115, 140) had the same power output. The 1984 140 V4 crossflow was identical to the 1985 115 V4 crossflow. The 84 was flywheel rated, the 85 was propshaft rated.<br /><br />Yes, you can bolt on the bubble back pieces to a flat back block. Will it dramaticaly increase the top end? No.

 

[Dhadley]

Re: 100,112,115HP differances???

I guess I should have explained a bit more. See what happens when the phone rings??<br /><br />Anyway, you still end up with the same bore, stroke, intake, ignition and gear ratio. Just for some interesting info we used to run a 15' Allison. With the V4 crossflow we had to run a stock powerhead but we were allowed "bolt ons". And we still had to run one venturi for each cylinder. IE -- the stock 2, 2 bbl carbs. We couldnt run 4, 2 bbl carbs.<br /><br />The boat would run right at 76, probably more like a consistant 75. That was top end or 1/4 mile numbers. That was it. Nothing more.<br /><br />Then we ran a 2.0 V4 looper. Same rules, same prop, same gearcase on the same boat. The boat ran 82 in the 1/4 mile. We never did string it out to see what it would do on top end.

 

[Boilermaker]

Re: 100,112,115HP differances???

Thanks Dhadley>>I always get informitive answers from you!<br />So i take it my '78 115 x-flow would be equivalent to a newer 90HP>>>is that about right?<br />I would love to swap it out for a 120 looper.

 

[Boilermaker]

Re: 100,112,115HP differances???

So>>>110 thru 140 bubble backs were all the same??? <br />Just a matter of what year and what they wanted to call it I guess???

 

[Dhadley]

Re: 100,112,115HP differances???

Thats pretty much how the game was played. At the 1985 IMTEC in Chicago the 1985 115 cf was introduced as the "worlds most powerful 115". Technically it was identical to the 1984 140 cf.

 

[Dhadley]

Re: 100,112,115HP differances???

Yeah the V4 90 degree loopers are torque monsters but a bit heavy. The 60 degree V4 loopers are lighter and zippier for sure.

 

[Late Nites]

Re: 100,112,115HP differances???

why did they make the 94-96 johnson 112 spl? They already had the 115. I've even seen 115 spl on te water. WHAT'S THE DIFFERENCE and WHY did they do that?

 

[Dhadley]

Re: 100,112,115HP differances???

The "Specials" were versions of another motor that had no "frills". No oil injection and some even had power trim & tilt as an option. OMC said their marketing research showed that some pontoon boat owners didnt want TNT. They never talked to any boat owner I know of.<br /><br />There were 28s, 48s, 88s and 112s.

 

[Boilermaker]

Re: 100,112,115HP differances???

Do the 60degree loopers & 90 degree loopers have similar torque curves & output??? or are the 90* engines king of the anchor pulling contests?<br />Nothing like low end to make me smile <br />Give me a BigBlock chevy, or Mopar 440, or even the Ford 426 CobraJet>>>Got to love the low end monsters, especially the ones that can rev too!

 

[Boilermaker]

Re: 100,112,115HP differances???