Help needed to mod a 1980 Johnson V4 85hp

[71V153]

Btw don't do anything to the ports besides squaring them up.

[spybot]

The what heads should i look for ? I read somewhere that the heads can be skimmed but it makes very little improvement in compression. There are heads that have some kind of edging ??? or something in the squish band tht does the job ??? Am i right in thinking that i should also stick to the same year for the parts ???

[71V153]

Almost forgot. On the 140's the base of the exhaust bridge is sawed/ground off. Besides that the blocks are the same.

[71V153]

The what heads should i look for ? I read somewhere that the heads can be skimmed but it makes very little improvement in compression. There are heads that have some kind of edging ??? or something in the squish band tht does the job ??? Am i right in thinking that i should also stick to the same year for the parts ???

'76 are the highest comp. But you'll need '78 or newer to hang your coils on.

[spybot]

Would heads from a 1984 140 fit ?

[71V153]

What I meant about the exhaust chest:

[71V153]

Would heads from a 1984 140 fit ?

Should. Think that was the last year for the crossflow 140.

[71V153]

Fyi in 1985 that motor was detuned to become the prop rated 115. After everybody finally agreed to go from BIA(crank rated) hp, to prop rated.

[FMP]

It's been many many years but a bud did have a 140 block next to an 85. I recall us talking about the differences in the ports, size?

[spybot]

Cool i understand now

[71V153]

It's been many many years but a bud did have a 140 block next to an 85. I recall us talking about the differences in the ports, size?

Depends on the year. '78 up they're all the same.

[71V153]

Only difference being the exhaust cut out.

[FMP]

That 85 must be 77 lol

[spybot]

I think the hardest part to get here in Scotland will be the "Bubble butt exhaust manifold and chest."
But i can always look on ebay USA and hopefully find them
What does the cut out do for the flow ?

[spybot]

Lost me on that one FMP