Twin carb'd 440 Cyclone info needed

[jd_decalguy]

Need some info from some of you guy's on a starting point on a 440 Cyclone with twin Carbs
Like what mains are you running
what clutch weights ( Deere Part # )
what rear cam angle or Deere part number
what max RPM are you pulling
what is clutch engagement RPM
about what top end MPH are you experiencing
are both of your clutch's maxing out ie: Driven opening all the way, Drive closing all the way


Thanks

Grumpy on Chris's computer

[Viktory2k1]

I've been trying to find this out for a while. There are a few ppl here who have done it but no real final results yet.

[WinnipegStPaul9]

I put two carbs on a 72 Scorpion Stinger with a CCW 440 one time and it went somewhere around 182 mph (+or-)

Just sayin

[patriot]

how many states did it take to get to 182 mph?

[Viktory2k1]

KPH?

[jd_decalguy]

Here I thought a couple of guys on here would spread there secrets but I guess not??
BUT here is what we have found out so far.......
Keep in mind we are using a Polaris light weight track & Cat 8" drivers
We are at at 290 mains ( yesterday it was -7 out ) But were still maybe a little rich??
21/39 ( 1.86 ) gearing, this might be some of our problem with the 8" drivers maybe we should be down to maybe 18/39 ( 2.2 ), 17/35 ( 2.06 ), 19/39 ( 2.05 ) or 18/35 (1.94 )?????
It seemed to run the best using a green spring ( M68853 ) & " U-1 " ( AM55195, 61.5 gram ) weights in the drive clutch, as that at least closed the drive & opened the driven all the way so the belt went all the way.
We decided that we need just a little more Max RPM so I think were going to put a shim or 2 under the spring, As using a Comet light Purple spring was too much..
Right now were getting engagement around 5000 RPM & max RPM around 6500 RPM ( were trying to get this up around 6800RPM or so )
The driven is in hole number 2 with a new blue spring & a 44 deg Cam
The best we saw was 55-60 MPH

Grumpy on Chris's computer

[patriot]

i just did the twin carb on a 78 440 cyclone i tested very little with it but i am using 94 vm 34's the 2.0 throttle slides made it run very rich cnanged to 3.0's,210 main ,p-0 needle jet ,6dh4 jet needle and #35 pilot,still seemed a little rich on top end but was 30 degrees out i am also gonna change pilot too a #30 i am at around 1200 above sea level,this is basically the liquifire setup aside from the throttle slides and pilot ,mine is bored 20 over and mildly ported iam running a indy 340 yellow spring and r1 weights engagement is around 3800 the secondary is 38 degree and stock gearing,the clutching is pretty descent as it was before the carbs turns around 6200 to 6400 as the powerband is 6500 ,..these carb's have a smaller throat than the one's that came on the cyclone even though they are both 34's,290 main's seem like alot for that engine,even the liquifire fine tune manual called for 220's at 2000 feet between 0 and 40 degrees.... also i am gonna knotch the heel of the weight's with a round file for more engagement as these weights are 57 grams i believe ,lighter weight's let the engine turn as long as they can close the spring and not make the engine labor,clutching is always a mystery i like trying differant combinations until you finally find it...best way is lining up with your buddies and see who gets to the finish first

[lwb140]

kenny ,i did the dual carb deal on that x4 , but didnt do any tuning on it after i put it together , i jetted it to the l/f fine tune manual . it seems to start snd run fine ,so i left it alone , 40mph or 40kph either one is plenty fast for me on a midmount , 290s seem a bit big to me but what do i know , wade

[patriot]

jd decalguy...how did you make out on your dual carb setup..just curios..dave

[dap574]

Kenny, I was offline for awhile but I got out my cyclone and checked my mains out. Used LF 440 carbs and 220 pto and 200 mag. Runs strong but could use some more fine tuning. Plugs look good and the pto side still 50 to 70 degree hotter on the stand. That's testing with a laser temp gun on y pipe.
Good luck with it!
North Pole Dave

[jd_decalguy]

I don't remember what we ended up with right now ( maybe Chris or Charlie remembers? ) but Tucker was riding it out on the ICE at Waconia & I guess it ran ok?? it was bare Ice there so with the track not being studded it would be hard to get any testing done, maybe yet this winter??

Grumpy