Super Jet 701 jetting.

Location
CT
Ok so I tried all last year to get this thing dialed in with no luck. It will start right up and idle perfectly fine. It will rip your arms off at 5/8 to full throttle. But I have all kinds of bogging for just off idle to just over half. Carbs we're just rebuilt. Has stock n/s 145 main jet and 72.5 pilot. With the shiny silver spring. I am at sea level. Mods are factory pipe. Compression at 170 per hole. Aftermarket f/a. Lightened flywheel. It is a 62t/61x motor. Any help is appreciated. My fuel screws we're high 1/2 turn out and low we're 1 1/2 turns out.
 

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
If these are stock dual 38 carbs then those mains are way too rich. You should have 72.5-75.0 pilots and 130-135 mains, 1.5 n&s
When you change that jetting out, inspect the tip of each needle (of the n&s). If you see any wear at all, replace
 

Matt_E

steals hub caps from cars
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Location
at peace
That's a Factory B-Pipe I'm assuming?
If so, that's too rich. Might be about right for a dry pipe
 

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
Change that jetting.
Per Factory Pipe:
Main Jet: 135 (130 stock)
Pilot Jet: 70 (stock)
High speed screw: 1 2 turns out from closed
Low speed screw: 1 1/4 turns out form closed
Needle & Seat: stock (55 psi)
Spring: 95 gram
 
if your running aftermarket f/a your probably going to want to lower your POP. Your going to want to shoot for 22-27psi. I'd try 2.0 with a 80g spring or 2.3 with a 115 spring. Other than than Matt's got you pretty close for a great starting point

Mine is set up ada with 31 cc domes(198 p/hole), a/m f/a's, b-pipe wit mod chamber.

pilot is 75
mains are 135
n/s 2.3
115 spring
pop @ 22psi

low screw 1-1/4
high screw 1-3/4
 
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