Facts about Evinrude/Johnson racing outboards made my OMC

[lars strom]

Back in the early seventies my nickname was "Strömming"
Ström..ming is Swedish för Herring..the fish..!!
Even media used my nickname..

[lars strom]

UIM SD class.. Göran Borg from Kumla, Sweden in his D94 Clerici/Evinrude 50 winning in Stockholm 1976.
Thanks “Guran” for your picture/info.
https://www.facebook.com/groups/2043...1368630808152/

[lars strom]

In my world it was RS..not the other way around..

[lars strom]

The first Johnson V6 RS came out 1976 and was a cross-flow.
Thanks Roger H.

[lars strom]

Part of the UIM OZ class pit in Nottingham 1981.
You can see four brand new Johnson F1-V8 engines #1 Cees Van Der Velden, #9 Roger Jenkins #10 Tom Percival, 11 Bob Spalding and four Johnson V6 RS.
Picture credit unknown but thanks.

[2us70]

What kind of speeds were they getting out of a UIM SD boats back then? I was running SD in APBA at that time.

[lars strom]

What kind of speeds were they getting out of a UIM SD boats back then? I was running SD in APBA at that time.

I did send a text to Göran Borg in Sweden and he answered right back..

"Tja, jag kommer inte ihåg, kollade mest på en tryckmannometer och varvräknarn, har för mej att vattentrycket var 4,4 kg vad det kan bli i knop vet i sjutton. Kan det ha varit ca: 60-62 knop"


..60-62 knop is around 69-70 MPH

Yes..this is Göran Borg back in 1976 and he won the Swedish UIM SD class Championship same year with his #94 Clerici/Evinrude 50HP

[2us70]

Wow that is fast compared to an APBA spec SD boat. Can you show the UIM specs for the class? In 1975 62 mph was a race winning speed for SD in APBA.

[lars strom]

Wow that is fast compared to an APBA spec SD boat. Can you show the UIM specs for the class? In 1975 62 mph was a race winning speed for SD in APBA.

Well..the UIM SD class was totally dominated by the Swedish outboard factory in Uppsala, Sweden for many years. Outboards like Archimedes, Penta, Crescent, Monark & Volvo Penta was all the same and made in Uppsala. Production outboards max 700 cc was the rules.
You could use a v-bottom or cat.
Up to the end of 1974 v-bottom boats powered by an Uppsala built 3 cylinder looper engine won everything. (V-bottom #5, Per Isacsson)


1975 Christian Mollgaard surprised the Penta world by winning big..European SD Championship race with his own built #5 SD class boat powered by an Evinrude 50 HP.
The second picture show Christian and me after his big win in Torsby, Sweden 1975.
After Mollgaard's win most SD boats was cats..but Evinrude 50HP was winning most of the races.

[2us70]

That is impressive. We were running motors about 20cc bigger than you guys were at the time but quite a bit slower. Were those motors 2 cyl loopers? Also I noticed a difference in the lower units on the orange Crescents. Were some gearcase mods allowed?

[lars strom]

The newer ones had a better gear-case. All the UIM SD class engines built in Uppsala, Sweden was 3 cylinder, loopers just under 700cc.
Carburetors on the side. Here is a Penta SD powerhead.

[lars strom]

Tomas Leidvik, Sweden and his UIM SD class Clerici/Sandvik/Johnson 50
1975

[lars strom]

1976 OMC came out with the Evinrude 55HP. This engine was a bit more cc and was over 700cc so could not be used in the UIM SD class.
Most drivers kept the 1975 50 and continue in the SD class 1976.
First picture
Second picture is the 1976 retail price list

[lars strom]

The new 1976 Evinrude 55 was not a UIM SD class engine..over 700cc.
(Later I think 1978 the Swedish Powerboat Federation changed the max 700cc to a higher number for local Swedish SD class racing)

The picture is the 1976 Evinrude 55HP

[WaterZebra]

The new 1976 Evinrude 55 was not a UIM SD class engine..over 700cc.
(Later I think 1978 the Swedish Powerboat Federation changed the max 700cc to a higher number for local Swedish SD class racing)

The picture is the 1976 Evinrude 55HP

Wasn't the powerhead and cowling incorporated into the SST45 engine?