- Location
- Granbury, TX
I've been searching and reading for days, but all of the threads I find either go off topic or go nowhere.
My setup:
Squarenose
701 (62t/61x) stock porting
.5mm over wisecos
ADA with 35cc domes
Dual cooling
Jet works FCV
RAD flywheel
Enhancer
Factory B-pipe (limited)
1 screen per side in stock F/A
Solas 14.5/18
At sea level (Houston, TX)
Carbs:
Stock dual 38's
High = 135
Low = 75
High screw 1 1/4
Low Screw 1
Pop Off = 40 psi (feels dead on response wise)
Pipe:
Bottom Closed
Mid open 1/2
Top open 1 1/2
I broke the motor in on the above setup which was rich and actually gave good bottom end snap, with a flat spot about 1/2 throttle and then top would build and scream. Today I started messing with my pipe screws (to heat up the pipe) and now am baffled as to what is going on.
I started to close the b-pipe screws to heat up my pipe. I went 1/2 turn in on the top screw (pipe) and noticed the motor started to lean out. I was just trying to get the pipe hotter and kept messing with it.
Went to top screw 3/4 open, mid 1/2. About now the motor started to bog on the low end and surge mid-top. Pipe was still cool.
I fattened up the low (carb) screws to ~ a little more than 1 1/2 out. Pipe still cool, motor still boggy and surging. Plugs show motor is lean.
What I am looking for is good bottom snap, with the ability to run WOT for long periods of time. My initial settings were pretty damn good minus the flat spot from mid to top end.
I know that by messing with the water screws I am affecting the sonic wave speed, apparently enough to lean out the fuel/mix due to scavenging effects.
i know this is a super common setup, and was wondering if anybody had any input as to what I should be close to on jetting/screws as well as water screws. I just want good linear response from bottom to top with a good hit on the bottom and not blow my motor going full throttle. Any input is greatly appreciated.
My setup:
Squarenose
701 (62t/61x) stock porting
.5mm over wisecos
ADA with 35cc domes
Dual cooling
Jet works FCV
RAD flywheel
Enhancer
Factory B-pipe (limited)
1 screen per side in stock F/A
Solas 14.5/18
At sea level (Houston, TX)
Carbs:
Stock dual 38's
High = 135
Low = 75
High screw 1 1/4
Low Screw 1
Pop Off = 40 psi (feels dead on response wise)
Pipe:
Bottom Closed
Mid open 1/2
Top open 1 1/2
I broke the motor in on the above setup which was rich and actually gave good bottom end snap, with a flat spot about 1/2 throttle and then top would build and scream. Today I started messing with my pipe screws (to heat up the pipe) and now am baffled as to what is going on.
I started to close the b-pipe screws to heat up my pipe. I went 1/2 turn in on the top screw (pipe) and noticed the motor started to lean out. I was just trying to get the pipe hotter and kept messing with it.
Went to top screw 3/4 open, mid 1/2. About now the motor started to bog on the low end and surge mid-top. Pipe was still cool.
I fattened up the low (carb) screws to ~ a little more than 1 1/2 out. Pipe still cool, motor still boggy and surging. Plugs show motor is lean.
What I am looking for is good bottom snap, with the ability to run WOT for long periods of time. My initial settings were pretty damn good minus the flat spot from mid to top end.
I know that by messing with the water screws I am affecting the sonic wave speed, apparently enough to lean out the fuel/mix due to scavenging effects.
i know this is a super common setup, and was wondering if anybody had any input as to what I should be close to on jetting/screws as well as water screws. I just want good linear response from bottom to top with a good hit on the bottom and not blow my motor going full throttle. Any input is greatly appreciated.
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