Where can I get Crescent 500 cs specs?????
Printable View
Where can I get Crescent 500 cs specs?????
One thing I can tell you about that motor is that it was made by the same folks as Volvo penta. The Cresent was a three cylinder that had about 30 cubic inches of displacement. No actual horsepower was given that I know of. It is quite rare and was only produced for a short time in the early to mid sixties. Fact is, it was so fast that the APBA had to give it its own class. It could do around 90 or more on a "C" hydro with no problem. It was too powerful for the mercs to have a chance. When Champion made the Hotrod, mercury simply got APBA to acknowledge a mod kit as legal for stock class on their old 20H so it could survive and win again in "B" class. An engine like the cresent was too much and it would take a looper to have a chance with this stock motor. Mercs didn't have a chance in "C"stock against this, so APBA started the "C" superstock class for the cresent. I don't know where a spec sheet or pic of one could be found though.Quote:
Originally Posted by OUTBOARDER
Found a link to view 1978 APBA INSPECTION SHEET but did not work..........................:mad:Quote:
Originally Posted by champ20B
Check your email I sent the 1978 APBA Crescent specs this morning.Quote:
Originally Posted by OUTBOARDER
Let me know if you received them.
Attachment 57541Attachment 57542Attachment 57543I seem to recall that the motor was a Saab model 93, 93 95 or 96 car engine with reduced displacement mounted upon a racing lower unit. From the late 50s through the early eighties Saab car engines were 3 cyl two stroke engines and yes you had to add oil when you filled up with gas. Saab got the design from DKW. Attached are photos of the Saab car, the Saab car engine and the Crescent racing motor.
very Cool!
Remember getting a ride in a SAAB like that when I was in college; slowest car I ever saw!
Jeff
My brother Alan still has a Cressent from way back when we had full fields of boats. He and I also took a DKW engine and built a garden tractor around it. I was the first to drive it or should I say aim it. The first run I did a 180 barrel roll off the rear wall of my house. That thing had so much torque just easing the clutch would lift the front wheels off the ground.
David
Nope, AFAIK there are no relationship between the SAAB and Crescent engine. I will speak to a couple of knowledgeable people and see what I come up with...Quote:
Originally Posted by seacow
Agreed. Its top speed was rated at 75 mph. But back then the original VW bug had a rated top speed of 68 mph.Quote:
Originally Posted by Fastjeff57
More about Crescent from dicko'dea.com
The Crescent Engines Story:
In 1964, I was invited to participate in the World 500cc Hydroplane Championship in Stockholm, Sweden. I was invited by a friend to drive a Crescent powered Hydroplane. The only stipulation being that I had to bring my own boat and propellers. Sid-Craft built an 11 Ft. hydroplane and shipped it to Sweden before the May 30, 1964 race.
I arrived about a week before the race and we did some testing on a small lake outside of Uppsala, Sweden. After I finished testing and feeling I had the boat going quite well, I was asked by the people of the Crescent company to let a German driver, Walter Vicer take a test run in the boat. He was used to driving a lay down hydroplane instead of a kneel down hydroplane, he was not familiar with the handling. On the 2nd or 3rd lap around the lake, he lost control of the boat and crashed into some large rocks at the end of the lake. He was quite severely injured. After looking over the damage, I felt the boat was beyond repair.
The crescent people contacted a cabinet maker in Stockholm, Sweden, and in record time he was able to repair the boat and I was able to compete in the championship race. After all the excitement, I finished 2nd in the World 500cc Championship. During talks before my return to the US, it was decided that I would be the North American distributer for Crescent Racing Engines.
The first alky engines arrived in the fall of 1964 and by 1965 the C-stock engines had started to arrive. The Super C-class was formed in APBA and competition began. After about 25 of the C-stock engines had arrived, I was advised by the factory they would no longer supply lower units or drive-shaft housings. They were kind enough to supply me the patterns and we started production of these items in the US. Approximately 25 drive shaft housings were built, 50 lower units, and we used Mercury clamp brackets to finish things off. All told, close to 50 C-stock engines were sold before Powerhead Productions had ceased and about 25 of the alky engines had been delivered in the US. The factory finally decided it was not profitable to manufacture anymore powerheads and we discontinued selling the engine.
One mystery that should be cleared up; is that the only difference between C-stock and C-alky engine was that C-alky engine had higher compression and used 3 large O’Dea built alky carburetors.
Today crescent engines have become quite collectible. A small group of Crescent owners in Sweden, still race the engines today with some small parts being made by vendors in Europe.
I always wondered, how much horsepower these engines made in competitive-stock set up. I read somewhere that they came with a interchangeable tuned pipe in the exhaust. One was for short coarse and one for long coarse. Also, what level of RPM could these engines handle? I don't own one, but in case one day I come across one I sure would like to know more about it. These are interesting engines.Quote:
Originally Posted by seacow
Further clarification. I asked Dick O'Dea if the Crescent was derived from the Saab motor. Here is the reply, although this still does not tell me if the motor is derived from a Saab design.
"The Crescent was built by Monarch Crescent, they also built bicycles and mopeds.
some of the same engineers may have been consulted. Most of the powerhead main components were made in Germany. M.C. was later purchased by Volvo Penta.
-Dick O'Dea"
From an article in "Nymans Vänner"
Gösta Stillerud, Thure Åkerfldt and Carl-Erik Zander was in the original group that developed the engine, they worked for Nymans Verkstäder (the company that built the Crescent engines)
The engine delivered 58hp (CS version) and 80hp (in C version) on methanol. At the time the Swedish speed record for C class was 92mph, of course the engine was a Crescent:)
I figured it would be in the 50-60 hp range (stock) especially after racers would fine tune it. One thing about it is that I think it was based on the Archimedes Monark 35 and 45hp models If I'm correct. These were nice fishing motors that were 500cc and three cylinders. The strangest of this line though, was the Drive-45. This was a inboard/outboard set up with a tractor unit (backwards prop).
( I'm glad they chose Archimedes for a name instead of Da Vinci ... Leonardo was a great artist and visionary, but he was a real lousy physicist when it came to engineering !! LOL)
Da Vinci: The inventor of the 1000lb wheelchair and no where close to the genius of Archimedes!!!!!
There's a U-Tube video of a Crescent out there.
Jeff
There is actually several:)
http://www.youtube.com/watch?v=A5hgTKdqATM
Very nice engines, but I'm quite biased as I own at least three Volvo Penta / Archimedes Penta VP700 and they were from the same factory (they are not related from a technical point of view though)
Are they piston port engines, or is there a reed vale hiding behind the carbs?
Jeff
I recall a C-Hydro race at St Joseph, MO (1966/67 ?) in which Bill Seebold was driving a Crescent. It sounded like it was having fuel problems, but about 1/2 way through the race it cleaned out and looked like it had 5 mph and a ton of acceleration on everyone. I don't recall where he finished or if he finished at all, but when it was running it was in a class by itself.
Here's what I recall about the alky Crescent:
- Pure piston-port intake with no reeds.
- Central combustion chamber.
- Slightly domed pistons. One ring(?).
- The compression was very high.
- The bottom exhaust passage was angled upstream slightly.
- The exhaust inside the housing was a straight pipe and short (6" or so) megaphone.
- The entire engine assembly with housing and lower unit was very light.
- The cylinder walls were chrome plated (I think).
Overall, I thought it was a very impressive engine, but then I've always been a fan of 3-cylinder engines. The only possible show stopper for me would be the chromed cylinders.
Frank
Quote:
Originally Posted by Frank Volker
anyone know actual Port Specs ????
Per is correct, there is no direct relationship. In truth, they are radically different motors, only sharing the 3 cylinder inline, 2 stroke commonalityQuote:
Originally Posted by Per
Here are the NOA specs of the Crescent Alky
If you are looking for a port map with the widths and contours, you will probably have to purchase a motor and disassemble it.
Frank is correct, piston port intake with a rear wall transfer port complementing the side transfers. The cylinders were chrome directly on aluminum, so they were not repairable in that era.Quote:
Originally Posted by Frank Volker
There was no interchangeable tuner.
It was not related to the Archimedes Monark triples either.
The reason it was abandoned was the cylinder spacing was so tight there was no room to alter the porting or make any other changes to the design ... the power had been surpassed by the 1966/67 Konig VC design motor and was obsolete without a complete redesign from the ground up. The cylinders lay together slightly tilted so the port passages of the center cylinder interlay between those of the top and bottom cylinders. Tight, compact, light and - stuck as a design build.
Had to look thru a couple hundred pages of archives ... rpm range around 8,000
these numbers make sense, exh opens at about 87 deg atdc and trans at about 114 deg atdc (like omc 49)Quote:
Originally Posted by Mark75H
thx Sam
Quote:
Originally Posted by seacow
No more to add to the info re: the 500cc o/b, but I did own a MONARK motorcycle for a time back in the late 50s.
It was a 350cc 2 cylinder, 2 cycle, 3rd port motor.
For that era, it was ahead of the Brit bikes.
Also this brochure on a MONARK 250cc twin . Note this motor is a JLO.
a well known German maker of 2 strokes.
All to say they were well capable of producing a 3 cyl o/b.
Attachment 57692Attachment 57691
Might better double check that info about the tuner.......It did have two different length internal pipes. One was for long run coarse and one for short. They were easily changed out according to historian and collector, Mark Suter. This engine was very similar to the Archimedes 45 hp and was actually close in horsepower output. The Cresent was likely the same as any other manufactured race outboard as to be derived from an existing domestic version engine with only few changes and castings. It is doubtful to me as a former machinist, that a production company would tool up just to make one special race engine totally separate from any other components they make for other use, in such little quantity. It is likely that with a little research, one could interchange some parts to build a Cresent engine from an Archimedes or Volvo the same as a Sweet 16 champion can be used to build a 6MMHR hotrod... or.....a Merc200-250 to make a 25SS. There's probably nothing outstanding to it at all. This engine could probably be built as a COPO. That could be a good idea to possibly consider, building a good historical race engine for anyone who would like to have one of these.Quote:
Originally Posted by Mark75H
Doubtful or not they did. It is a unique project. Unlike OMC, Mercury and Champion, they did not build the C off of any of their production parts.
If you read Swedish and German there is a bounty of documentation of the development of the project. The tuner was not an option thing, like the super long nose cone on the record motor, it was a one off piece. Probably only 1 or 2 made, its not like you could order one - more like the factory made ONE for themselves to use. I don't consider that a regularly available part to say "They made this and that and the other." Do you follow me? Its like the Merc dual torpedo SuperSpeedmaster unit.
There is a guy in England building such a replica, but it is very different from a true Crescent C racer; essentially NO C racer parts are on his replica other than the orange paint.
No COPO here.
OK, I will bite, what is a COPO ? :pQuote:
Originally Posted by Mark75H
It is just a term "car guys" use......Basically, it is building a factory muscle car or truck to correct or close specs using a basic format and select parts.Quote:
Originally Posted by BRIAN HENDRICK
I had a project going for a short while where I and my dad were building 1960s and up factory performance trucks, similar to original factory options. We built four total. The last one I did was a 1980 Dodge 100 "Custom Sport Special-stepside" equipped with the ramcharger buckets, steering, carpet and aluminum factory wheels. It had the last of the 440 cubic inch based on the six-pack version internally, though I built this engine using a correct carter 4BBL. It had hemi springs with the six-pack cam and 10.5:1 compression with 906 heads. I built this engine by my particular recipe of my own choice parts and it dynoed at 527BHP on 97 gas. It idled very nice and was a comfortable driver for example. It looked like a factory Warlock all over. Not like a typical hot-rodded tricked out sort.
There were some radical trucks built from 1964 and on that few know about. Ever seen a 1964 dodge 100 with a cross ram 413(dual quads)? yes, It really happened. It was the line of special "CSS" dodges. That's another thing though.
BACK TO OUTBOARDS!!
A replica assembled from factory original parts. The O'Dea racers were essentially COPO replicas; made until the part supply was exhausted. It can't be done now because there were no parts common to the production motors.Quote:
Originally Posted by BRIAN HENDRICK
Apparently, my research is all questionable.
Comparisons between the Archimedes Penta 450 and the cresent 500 are as follows:
The bolt patterns are identical on the head cover, and the exhaust cover and the block as well between a 450 and 500. They do have different casting finishes, but hey....look at the 18mm head on the Hotrods right? Not found on fishing motors. How bout a 20H crankcase or cylinder block....is it all together like any merc fishing motors? NOPE.
The 450 has only one carb (very similar or same as the racer carb models) though the 500 racer has three. The thing is that they are mounted in the exact same place on the cylinder block. Bolt patterns are alike. The flywheels are different but so are other factory racers....
I'm sure that the internals such as rods, bearings, cranks, and probably pistons are the same. How could there be any doubt? The Archimedes 450 (45hp) fishing motor would make a 55 merc look pathetic in performance...It was a real powerful and underrated powerhead itself that with a racing gearcase and mid, would send a Mark 55H into the stone age where it belongs with all the other deflector piston Kiekhiefers as far as racing goes.
They both have the same bore, same stroke, 500 CCs, and three cylinders. It (the 500 racer) was only rated at just over 50 Hp. Though it had much more just like the 450 had. Those engines were so good that the company offered a reward to any customer who could find a better motor of equal factory rating. That's how BAD TO THE BONE they were...
Early on the CS was rated at 58hp, Henry Johannson says later on they were 65hp. Dick O'Dea stopped making and selling Crescents because Crescent could no longer supply cranks to him to assemble new motors. I might have a copy of the letter advising him that there were no more cranks.
Looking thru my collection of pics I found 4 or 5 newer bigger Crescent powerheads mounted on the racing mid and foot. The 65hp has 3 carbs but an elbow so the inlet faces front. Altering it to resemble the alky version with the plate to accept the bigger Amal carbs would make it look a lot like the racing block.
The Crescent 500 "Wizard"..;)
But as fragile as the Crescent gearcase is known to be ... I'd bet against it in a heartbeat:(
Dudley Malone and one of his friends got ahold of the Crescent racing foot patterns and made a foot they called the Inson, but it wasn't successful in APBA Mod racing.
WhWhWh.....WHAT???!!!! HOLY SMOKE!!!! What do you call that set-up... the "Grim Reaper Special"??? That is a wild looking engine, engines......well, its BAD TO THE BONE!!Quote:
Originally Posted by Lars Strom
Well, what would you call 2 newer 500cc Konig's back to back? - probably more than twice that much power?
a 360+hp 10,000rpm "ultimate alky obliterator!!!!"Quote:
Originally Posted by mark75h