Facts about Evinrude/Johnson racing outboards made my OMC

[lars strom]

No there was no production V-6 1973. The first production V-6 came 1976.

http://svera.se/blogg/facts-about-la...-and-eighties/

[powerabout]

No there was no production V-6 1973. The first production V-6 came 1976.

http://svera.se/blogg/facts-about-la...-and-eighties/

exactly so what was the xflow v6 in 73?

[Rotary John]

exactly so what was the xflow v6 in 73?

The 2 (two) V-6 that were introduced at Paris in 73 were sand cast cross flow blocks sleeved for 2l. The cranks were actually V-4 cranks cut and welded together. Most of the parts came from the production V-4 with the obvious special V-6 parts either hand made or sand cast. By the way, they were not "red" they were painted ROTARY orange. We had lots of spray cans of paint in the race group.

[powerabout]

The 2 (two) V-6 that were introduced at Paris in 73 were sand cast cross flow blocks sleeved for 2l. The cranks were actually V-4 cranks cut and welded together. Most of the parts came from the production V-4 with the obvious special V-6 parts either hand made or sand cast. By the way, they were not "red" they were painted ROTARY orange. We had lots of spray cans of paint in the race group.

Hi John
so dimensionally it was what became the xflow v6, same bore spacing and stroke and 60-30 degree firing to suit the welded crank?
Was it vertical or horizontal reeds?

[lars strom]

OMC never built a 2 liter production V-6 so every motor for the UIM
ON class was custom built.
As an exclusive Evinrude dealer I fully understand why OMC
racing preferred to build race engine for the UIM OZ class instead.

[lars strom]

Most new race engine was introduced at the big races in Europe
1973 the first V-6 both from OMC and Merc in Paris
1975 the first V-6 2 liter looper from OMC in Cardiff, UK
1979 Merc came to Bristol, UK with the first T4 for the OZ class.
1981 OMC introduced the 3.5 liter V8 for the OZ class in Brodenback, Germany
I was at all does races and did see it with my own eyes.
OMC hired me 1975 to be a factory OE/F3 driver and later a F1-V8 driver.
Many good and fun memories.
Thank you

[powerabout]

OMC never built a 2 liter production V-6 so every motor for the UIM
ON class was custom built.
As an exclusive Evinrude dealer I fully understand why OMC
racing preferred to build race engine for the UIM OZ class instead.

Sure but it just a sleeved down what became a production v6 very simply based on a v4, lets see what JS says

[lars strom]

No a sleeved down 2.4 liter cross-flow production V6 to 2 liter could not keep up with the later Merc 2 liter V6.
The 2 liter looper V6 took care of the Merc.
I raced a 2 liter V-6 looper in Italy 1978 for team Saffa.

[powerabout]

No a sleeved down 2.4 liter cross-flow production V6 to 2 liter could not keep up with the later Merc 2 liter V6.
The 2 liter looper V6 took care of the Merc.
I raced a 2 liter V-6 looper in Italy 1978 for team Saffa.

and yet the looper never went into production?

[lars strom]

Well..the first OMC V6 looper production engine came 1986. In the beginning 2.7 liter and 1988 3 liter.

[Rotary John]

My comments were about the 2 motors raced in '73 Paris. They were the same dimensions as the V-4 with the bore reduced for 2l. The reeds were horizontal like a V- 4 with 3 - 2 barrel carbs.I don't believe the 2l cross ever went into production as the first OMC V-6 production motor was the 2.4; a V-4 with 2 more cylinders. The loopers came about after I left.

[lars strom]

The production V4 90 degree 2 liter looper, production V6 90 degree 3 liter looper and the production V8 90 degree 4 liter looper are using the same pistons and rods.
Started 1985 and the 2,3 and 4 liter came 1988.

[lars strom]

The 4 liter production V8 looper was a completely different engine from the F1-V8 race engine.
Not one part was the same.
My Skater 32

[lars strom]

... The loopers came about after I left.

Rotary John,
You did plenty of work for OMC and the Rotary development.
I don't think any outboard can beat the world attention the Rotary race engine gave OMC.
To bad Mercury stopped the OZ class in Paris 1974..
Well a special experimental class made us see them race that year in Paris.
Later when Merc came out with the T4 1979 suddenly the OZ class was a good thing again in Paris.
Again thanks for all your work Rotary John.

http://svera.se/blogg/the-omc-rotary-300-hp-racing-outboard-40-years-ago/

[powerabout]

The 4 liter production V8 looper was a completely different engine from the F1-V8 race engine.
Not one part was the same.
My Skater 32

the flywheel nut and the spark plugs. lol