Help needed to mod a 1980 Johnson V4 85hp

[racer]

1.92 shift hook up is different as is direction.

[phillnjack]

what do you mean by direction ?

[BarryStrawn]

If you use the whole 1.92 gearcase then it shifts backwards. Or you can modify the 1.92 (13:25) forward gear to run in the newer case which will shift as normal. You have to grind off the pump drive. But good luck finding a set.

[olboatman]

Thanks guys for the replys and info! Gary

[powerabout]

If you use the whole 1.92 gearcase then it shifts backwards. Or you can modify the 1.92 (13:25) forward gear to run in the newer case which will shift as normal. You have to grind off the pump drive. But good luck finding a set.

Would you weld a new style shift rod on to the top of the older one so you can hook it up?

[BarryStrawn]

No, I would run the mechanical shift case with 1978+ shifting.

[powerabout]

No, I would run the mechanical shift case with 1978+ shifting.

and make the gears fit?

[gs400l]

i read this thread and i dont see this trick i made a tool out of flatbar bolt down to head bolt holes drill and tap for 1/2" allthread with rotateing assimbly installed rotate to bottom dead center and lock it in place eith the allthread drill holes where circles are drawn (i drilled them 1/2") CAUTION MEASURE TOP OF PISTON DOWN AND GET THE HOLES JUST BELOW THE BOTTOM RING LAND inside the cup of the piston fule charge is trapped this is the same effict as finger port on a looper

and make the gears fit?

[71V153]

Stick to '78 or newer and ya won't have any problems. All the chit bolts up.

[racer]

Powerabout You could weld top of shift rod or do as Barry mentioned and put the 1.92 gears into a newer case but you need to be careful shimming.

GS adding the extra holes in the sleeve and piston helps but not nearly as much as finger ports.

[spybot]

i read this thread and i dont see this trick i made a tool out of flatbar bolt down to head bolt holes drill and tap for 1/2" allthread with rotateing assimbly installed rotate to bottom dead center and lock it in place eith the allthread drill holes where circles are drawn (i drilled them 1/2") CAUTION MEASURE TOP OF PISTON DOWN AND GET THE HOLES JUST BELOW THE BOTTOM RING LAND inside the cup of the piston fule charge is trapped this is the same effict as finger port on a looper

What does that do to the engine ? Is this to do with my posts or the gear ratio.

[gs400l]

What does that do to the engine ? Is this to do with my posts or the gear ratio.

it does tthe same thing as the scallop piston skirt allows better transfer of fuel charge from crankcase to cylender (hp gain)

[spybot]

it does tthe same thing as the scallop piston skirt allows better transfer of fuel charge from crankcase to cylender (hp gain)

So would this be done along side the scalloping ?
Or would this be a stand alone replacement to scalloping ?

[gs400l]

So would this be done along side the scalloping ?
Or would this be a stand alone replacement to scalloping ?

i did both plus some other stuff it was winter experiment

cut down front half "manifold surface" to stuff crancase
ports same as 140 it was 85 block
weighed all recp.parts and made them match (you will be surprized how much different they are)
heads from a 135 cut to get 140 psi
bubble back cut bottom in ex chest and cleaned up ex passage
cut tuner shorter ?
1 5/16 carbs from old 235
fiber reeds
low water pu that i cut off of and old inline merc

i collected a few blown up v4s and peiced it together for next to nothing 600 bucks if i remember rite new rings and a hone everything else used i put it on a hydrostream
vandal comp and it ran 79 mph still holding up 8 or so years i dont run it that much but when i do i dont baby it guess it stayed together cuz its so loose

[spybot]

i did both plus some other stuff it was winter experiment

cut down front half "manifold surface" to stuff crancase
ports same as 140 it was 85 block
weighed all recp.parts and made them match (you will be surprized how much different they are)
heads from a 135 cut to get 140 psi
bubble back cut bottom in ex chest and cleaned up ex passage
cut tuner shorter ?
1 5/16 carbs from old 235
fiber reeds
low water pu that i cut off of and old inline merc

i collected a few blown up v4s and peiced it together for next to nothing 600 bucks if i remember rite new rings and a hone everything else used i put it on a hydrostream
vandal comp and it ran 79 mph still holding up 8 or so years i dont run it that much but when i do i dont baby it guess it stayed together cuz its so loose

Hi GS thats exactly what i am struggling to do. Can you explain this a bit better please "cut down front half "manifold surface" to stuff crancase " I have the following just now.
A set of H/C heads from 140
Bubble butt Exhaust plates from a 140
Carbs 1 5/16 from a 140 (plus reeds and intake)
I have ordered CCMS sport reeds
I have been collecting as much info as i can. This will be a winter project so if you can steer me in the right direction that would be great.
The reeds i can pt on to my 85 for this season, i am looking at putting the 140 crabs on her as well but been advised that i will have to lean out the jets.
There will be a lot of machining to the block once its out the water. i know i have to machine the block for the exhaust. I will be scalloping the piston and block. I will do as you have done with the 2 holes. I will be balancing all parts.if i can find someone to balance and lighten the flywheel all the better. The gasket will be placed then all the faces machined to match. It will be a long haul but if i have the help im sure she will be a fast wee boat.