I've got a complete scat 1915 with c45 cam straight cut gears, 1.25 rockers, 041 heads with 40x35.5 valves, 1 5/8 exhaust, petronix ignition! I'm running a single hpmx 44 at the moment with no problems just want the response of the duals!
Whats your opinions the 40;s or 44's want the the best performance! Thanks

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Don't let out when in doubt!!

My 1915 has all scat internals also basically same motor youve got. I built it 2 yrs ago, But I run dual weber 40s and wouldnt have it any other way. Love them.

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"IT IS WHAT IT IS"

The 40's would be your best bet if your really set on going to duals. If you really want to wake it up on the low end I would suggest changing the cam to something smaller and going to an 1-1/2" header

Dual 44's that way you can jet the carbs to where it can run the 1915, if you go bigger, you can always jet the carbs to where it can run a big stroker, I believe the 44's are more flexible to use than 40's IMO.......

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"Loud pipes saves lives"

this is what i would do, ive got a 1915 with cb 044 heads and a vz15 cam with 1 5/8 tri mill and i have ran weber 40's and 44's and really couldnt tell much if any difference on the bottom side while trail riding and when climbing hills i usually dont cut it no slack so its not down around idle very much climbing

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Just Stand On It!!!!

Chris

x2
You will definitely feel the bottom end difference and more response with the 1 1/2" header. 40 duals with the right venturii and jets are plenty big enough all the way up to a 2500 for the woods. If u get Empi hpmx's, consider getting them thru Southern Buggies. They have an internal fuel bleed problem that Tim can fix right up before he ships them to you.

I know about blocking the choke tubes! Thanks for looking out!

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Don't let out when in doubt!!

i got a set of 40s through southern buggies...got the deluxe kit...got here quick...have heard that the 44s will load up with smaller heads.....these are the same carbs wrongwayray runs on his built 1915 and they run great!

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Hey,can you hand me those zip ties and that roll of duct tape?!

40 or 44 if your going to buid a big eng. in a year i would get 44 and put 32 venturies and 6'' velocity stacks. but 40 will work good to .

I was curious if the 6" stacks really made a difference that you could feel. CB claims up to 15% hp increase. Sounds VERY far-fetched to me. Any body tried them ( on an otherwise unchanged motor ) and noticed any difference?
Sorry to thread steal

ON the dyno 2165 44 carbs 120 cam S\E heads 9.5 to1 runing 93 gas . No HP but it made 18 ftp of TQ at 3000. The eng did not make more peck TQ it just made more TQ lower in the RPMs

X2 If you wont more TQ you need a small cam C35 w110 fk 41

wow! worth trying for sure

Ok guess I'm gonna go with the 40's so I don't have to change ALOT! Anyone recomend what size jets would be good! I run 50/50 93-110 fuel only!

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Don't let out when in doubt!!

The jets they come with will get you in the ballpark. Just do some plug readings after that. What is the compression ratio of your engine?

The jets i was recommended for my setup....well they ran about as good as a dog with no legs. When i went back to the buggy shop and told them wat i wanted they said i was crazy and it wouldnt run lol But what i have runs great. Ima be tearin the carbs down to clean them, ina day or two. Ill let ya know what i have, maybe get you a little closer. Either way plan on spendin some $$$$ on jets to get it right

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"IT IS WHAT IT IS"

For my eng. 40 where a little lean .When to 145 or 150 mains. Air cleaner and velocty stacks and fuel pressure 3psi will all play a part.

I have jets and don't plan on changing stacks and all that I'm running electric pump with 3 psi now! What size jets do they come with? Will the accl. Pumps be pre set from factory?

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Don't let out when in doubt!!

I think 135 mains and the pumps will be close. I would lower the floats a little for off road.

So will these dual 40's make a difference rather than a single 44???

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Don't let out when in doubt!!

I think so ! A set of duals run good.

Alrite I got the dual 40 delux set whith plates like the webers!

What siZe jets should I run?

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Don't let out when in doubt!!

Well you all know I am a EFI guy, but I do love how much everybody chips in knowledge for a guy when he needs it. Lets make sure that nothing changes this, it's the backbone of the site. Good luck with the new toys!

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[url=http://www.TickerFactory.com/]

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Ill pull one of mine apart tomorrow, and let you know what all I have inside

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"IT IS WHAT IT IS"

I have 50 idle 200 or 190 air and 150 main in my 40 webers on a 2165 . How does it run ? Make one small change at a time .