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Hi All,

Have the motor, have the sled.....was wondering if anyone ever did this swap....

Things coming to mind are.....

Carbs- Case mounted on RV also Mikuni's sit level....Is there room for them....
The bulkhead wall is fairly close as I remeber....

I'm pretty sure that they both have polar fire ignition.....

What is a good Rotary valve for this motor....not one in it right now....

Does anyone know squish tolerance???? I'm guessing it has to be greater than the
typical liquid .065..,....34's or 36's.....have both.....I kida want to use a single pipe
to try to retain as much torque as possible....any reason why i can't use a Formula
secondary and a TRA primary here????

Also would like to add a hydraulic brake......using TRS (blizzard) susp. in rear....

I would like to build a unique sled (this was my first sled 15 years ago)....
That I can trust to go 30-40 miles a couple times a year.......
oh and I can't stand tillotsons chronic warm flooding used to take 14 pulls wide open to start it after sitting still 10 min. without running.....at 13 this didn't leave
much energy for getting un stuck......If any of you veterans here would happen to
have tried or done this I would certainly appreciate some senior wisdom.....

Currently restoring a 90 406 ATK...........
 

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This should be a easy swap as ski doo used the RV engine on this chassies on the 1973 294 and 340 blizzard . You may have to re punch the free air motor mounts as early RV engines had one pto bearing and later engins had two . This changes the of set of the engine and the alinement with the secondary . the first production 340 RV had 38 mm carbs in 1975 the rest had 34mm carbs blizzards had tillitsons . the minimom squish for the RV 340 in 1975 race specs was .050 you may not want it this close for trail riding . the taper on the crank should be the same as a 583 so a tra should fit it will be just a mater of tuning .
both RV and Free Air used the same poler fire .
 

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I am basically working on the same project myself. I have a 73 F/A chassis and a 340RV engine that I have had kicking around for 15+ years. I just picked up a 73 Blizzard hood as well for it. I am going to try to mount a rear suspension from an 89 Safari into it. I know that the engine was an animal in the Moto Ski Sonic that I had it in so it should be really something in this smaller chassis. I swapped the Ski Doo primary clutch with a Comet using C-2 cam arms a nd a yellow spring. This combo was absolutely great with this engine and the stock gearing/carbs/pipes when it was in my Sonic. With my wife on the back with me it would still pull hard enough to stretch my arms right out all the way to 11000rpm.
 

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id keep the original motor int he original chasis, I think id be worth more in the future as for tht R/V thtz a really rare and nice sled
 

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You have to watch the jackshaft area. The 73 Blizzards had Tilly's on them so it was no problem clearing the jackshaft. The Mikuni's need to be somewhat level. You might have to shim the mounting studs up some. The 75 up R/V motors sat lower in the chassis than the 73/74. Also the only 340 made in 75 was in the Moto-Ski TS 340.
 

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Hey Vintage blizz , you should sell me you 340 RV engine for my sonic TS
. I have one that im going to build into a vintage racer
,but im am missing the correct engine
 

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Z
I have too much tied up in parts for this project to give up my 340RV motor. If I hadn't alread made the leap I certainly would have concidered it.
 

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degasus
I got rid of my RV and Sonic chassis' long before I knew the value that they now would have. Believe me I kick myself for it. I have had so many parts in my possession that now have value that I cringe at the fact that I sent them to scrap years ago. Many parts serviceable and some nearly mint.

lowtek
The thought of a 9500 engine crossed my mind but I already had the 340RV motor so that is the direction I must take..... unless somebody has a 9500 motor and related cooling parts to trade.......
 

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VintageBlizz said:
degasus
I got rid of my RV and Sonic chassis' long before I knew the value that they now would have. Believe me I kick myself for it. I have had so many parts in my possession that now have value that I cringe at the fact that I sent them to scrap years ago. Many parts serviceable and some nearly mint.

lowtek
The thought of a 9500 engine crossed my mind but I already had the 340RV motor so that is the direction I must take..... unless somebody has a 9500 motor and related cooling parts to trade.......

[snapback]791891[/snapback]​
Agreed
 

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I thought about doing the swap myself but the 340 RV was lighter than the 340 t'nt f/a so it didn't make much sense except it would be very cool!
 

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some guy sold 2 moto ski's a 340 and a 440 at a local swap 2 weeks ago for 350.00 each and they were really clean. I missed the deal by an hour. I offered 1000.00 each and he stuck to his earlier deal with the other guy that had to go get his trailer! ARRRRRRRRRG! should not have slept in.
 
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