90 hp 60 degree Johnson?

[RBR5]

I'm looking at a 1995 90 hp 60 degree Johnson was wonder if they will run with the 115 johnsons?
And what's the differnts in a 1995 60 degree 115 and 90 hp? They say the 90 will run with the 115

 

[Chris1956]

The 90-100-115 HP 60* motors share displacement. The 115HP is rated at 5000RPM, whereas the other 2 are rated at 4500 RPM. A lot of times the extra HP is gained by porting changes. Sometimes these changes reduce reliability or engine life. You might check the part numbers of the heads and blocks to see what is shared. It will help track down the differences.

 

[Faztbullet]

wonder if they will run with the 115 johnsons?

Nope.....115 has extra 25hp.

And what's the differnts in a 1995 60 degree 115 and 90 hp?

.080" in exhaust port height and intake window a tad narrower and jetting......

They say the 90 will run with the 115

They is misinformed....

 

[RBR5]

Could you put 115 carbs on a 90 and help it?

 

[racerone]

The blocks have a different part number.-----The blocks will interchange.------Different porting.

 

[Faztbullet]

Could you put 115 carbs on a 90 and help it?

Not really as jetting will be to rich on top end .

 

[emdsapmgr]

If you had two identical boats, one with a 90 and the other with a 115: you'd find the two engines would launch out of the hole similarly. After 150 feet, you will see the 115 will slowly start to walk away from the 90. Eventually it will leave it in the dust. 115's have different block porting (flow more air) and larger-throated carbs than the 90. (flows more air and fuel) The 115 has higher performance heads to boot. (heads are different part numbers.) When the 90 is screaming at wide open throttle, you can pull back on the 115 throttle. When the two keep pace with each other, you'll save fuel on the 115.) The 115 will run one higher pitch prop than the 90.

 

[bob johnson]

I took a 90 hp and made it into a 115.... the heads have a DIFFERENT CC's...the 90 hp head combustion chamber is DEEPER..... also the carbs bores are larger on the 115 hp.... as are probably the high speed orifices..... and as mentioned the piston bore sleeves are different..... the ports are in a different location.. and they are slightly larger on the 115............and the funny thing is the PROFESSIONAL engine builders market the 90 hp and the 115hp as the SAME SHORTBLOCK!!!! ha ha ha ha.... HARDLY!!!

 

[bob johnson]

The 90-100-115 HP 60* motors share displacement. The 115HP is rated at 5000RPM, whereas the other 2 are rated at 4500 RPM. A lot of times the extra HP is gained by porting changes. Sometimes these changes reduce reliability or engine life. You might check the part numbers of the heads and blocks to see what is shared. It will help track down the differences.

actually in the books I have (factory) they rate both the SL models (90 and 115) at the same RPM 5000... they rate the GL model 115 at 5500 rpm....(faststrike and intruder)

bob

 

[emdsapmgr]

The intruder/faststrike 115 models make between 5 and 10% more hp than the 115 decal on the side of the cowling.