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Discussion Starter · #1 ·
Ok, need some jetting advise......With DFR duals, Uniflow/Hardstyle intake with no lid and 44mm bored carb, what jet do you think I should be running, and how many turns on the fuel screw.

Ive tried a 190, 195 & 200 and get the same results with each! Plug is light brown and Im topping out at about 56/57MPH. I have an A/F guage that better be hear tomorrow so that should help with figuring this out. Im starting to HATE these duals!!!! Ive spent more time dicking with this thing than I have actually enjoying it, and it never feels right!!!!! :1zhelp:

:wtf:
 

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Discussion Starter · #3 ·
I have the high-flow one on there......I cant imagine that being too small??
 

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Ok, I'll go into more detail. I've had good luck with upping the pilot jet as well. You should try a 50 or 55. I have a spare 50 you can try this weekend if you like. The other thing is to move the washer on the slde needle to richen the acceleration part. For the main I think you need to be light tan, probably where you are now. If you keep going up on the main and it stays the same then you have the maximum fuel the pump can deliver. Try putting some restriction in the return line to reduce the return fuel and see how that helps.

Did you install that aftermarket fuel pump yet?
 

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Discussion Starter · #5 ·
Yep, running the new pump........already have the washers flipped. I was gonna pick up some pilots tomorrow and try those, Im sure that'll help some. Didnt think of the fuel return.....I know my return line is larger that the stock one so Ill try that!
 

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Do you have a sheave installed? If not 57 is very good for top speed. If you do have a sheave then the 57 is the normal speed people see.

I had the same symptom as you with my stock fuel pump. I kept going up on main and nothing happened. Then I changed the fuel pump and I was very rich. Maybe you should make sure the vacuum line doesn't have a crack or pinch. I bought aftermarket 1/4" fuel line and made a big loop with the return to make it harder for the fuel to go that way.
 

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You don't want a larger return line. If you look at the y fitting the return is smaller. make the return part of the Y stick straight up in the air and loop the line around to the tank. This way the fuel has to work harder to go that way.
 

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Discussion Starter · #8 · (Edited)
You don't want a larger return line. If you look at the y fitting the return is smaller. make the return part of the Y stick straight up in the air and loop the line around to the tank. This way the fuel has to work harder to go that way.
So, do you think 56/57MPH is pretty respectable (I have the sheave)? Im running a 5/16th "T" in place of the stock one, but it's connected to a short section of the stock return line, then it to 5/16th right before the tank. I added a few zip ties to the stock return line coming off the 5/16th "T" to help add more restriction. For some reason the stock "T" just wasnt good enough for me......just had to have a shiny brass one!

Oh, and the vacuum line Im using is just a smidgen larger than the stock size. The auto store didnt have an exact match, but this one is pretty damn close!
 

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Why don't you use that shiny T and get both outputs from the new fuel pump and reconnect the plastic Y for the return line. You don't want a big return line. If you look at the plastic Y the return line is reverse of the flow direction. It isn't actaully supposed to flow from the pump but rather to bleed off excess back pressure when the line to the carb is full of fuel and building pressure.

I'm not sure that DFR noise maker you put on the back is going to be the performance ticket you thought. Is it the looney tunes duals or are they selling the new 2 brothers duals? I've heard the 2 brothers are goods but the looney tunes duals do nothing.

57 MPH with 25" tires on the digi dash is the norm with the sheave. I checked with GPS and it was only 53MPH. If you have 26" tires then digi and GPS should match and 57 is pretty good.
 

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Oh, and the vacuum line Im using is just a smidgen larger than the stock size.
I'm not positive the big vacuum line will do what you want. The restriction is still in place at the carbuerator and now it will take more time to build a vacuum in the larger line.
 

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Discussion Starter · #11 ·
My duals are the DFR/LTE ones. I was gonna sell my duals and get the Alba or ACI setup, but WOTM convinced me to keep these....Bummer!

Maybe Ill just throw the stock "T" back in.....Hmm, speaking of "T", I think I need a beer.
 

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Discussion Starter · #12 ·
Ok, stock vaccum line going back on.....Geez chandler, youre throwing all my pretty hose jobs right out the window! :D
 

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Do you think the stock "T" may be restricting fuel flow?
I wouldn't worry about the stock vacuum until the return is squared away and you take a full throttle reading. If you jet rich then you have enough fuel. Don't expect a big change though because your spark plug is tan now so your getting the amount of fuel the engine wants.

Yes the T will restrict but I've never heard of the stock T causing a problem. I've heard of a bunch of issues with the return robbing fuel from the carb. With a bigger return you've lower the pressure to the carb and the flow to the carb.
 

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Discussion Starter · #15 ·
Gotcha......I have the stock "T" back on with the stock return......Im gonna run it again in the morning. I owe you a beer this weekend!

Thanks for all your help tonight!!!
 

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I have a 55 in now and I still think I got my best acceleration with a 50. I'll be bringing them all this weekend.
 

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Discussion Starter · #18 ·
Hmm, gonna need to make a jet run tomorrow........tomorrows gonna be a busy day! You leaving for Buttercup tomorrow?
 

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No I got to work tomorrow. I will get out on Friday. Save me a spot for my Jeep and trailer and a place to throw down my tent.

I will look for you guys at the end of the road off of Grays well. I think you guys go to the left at the T. Is there any special way to pick out the camp or should I just look for the big white toyhauler? :33:
 

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Discussion Starter · #20 ·
Yep, go left and all the way to the colda-sack. Were usually to the left from there.......Most of our group left today so Ill know tomorrow before we leave where were gonna be. Ill make sure you know where to find us...and Ill PM you with my cell.
 
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