Thread: gpr no low end torque
08-27-2007, 09:34 PM #1
gpr no low end torque
need help from the carb experts, 02 12r 140psi r & d heads and just put in carls vf3's and rejetted to 125 mains 110 pilots 1.5 n/s 95g spring from carl, adjusted pop-off at 42-43 psi turned out lows 1 turn out and highs 1 1/2 out, idle is at 1400-rpm -----------now heres the problem it idles perfect but if you accelerate it wide open it boggs out real bad for like 2 seconds like bbbbwwwoooooaaaaaarrrrrrr and then goes, if you accelerate slowly it goes fine, mid range and top is crisp very responsive i thought i was lean on the lows so i opened the lows to 1 1/2 but it didnt help could it be to rich/ lean or can the pop-off be to low/ high. plz help dont want this one to be the second one i sieze
08-27-2007, 09:37 PM #2
I'm no expert but the lows are very sensitive to adjustment. Going out 1/2 on the lows was like going from Earth to the moon. You may of went from too lean to too rich? I would try 1 1/4 and see how it is.
08-28-2007, 06:30 AM #3
- Join Date
- Jan 2006
- Texas City, Texas
You would need to have your choke plates in to try this......
Close your choke 1/4 on your 1st run
Close your choke 1/2 on your 2nd run
Close your choke 3/4 on your 3rd run
Once it gets into the high speed circut, (higher rpms) close off the choke. If it runs better on any run, then you are starved for fuel on the bottom.
Without choke plates, try tapeing about 1/3 of each flame arrestor with duct tape. This will temporarily increase your vacume. If your bottom end comes alive, then you are starved for fuel on the bottom.
If this works, open your bottoms 2 turns out. If this is still not enough fuel on the bottom, you may have to rejet to 115's.
I had to do this to mine. In fact, I had to lower my pop off pressure as well. It worked out fine.
All of these test are designed to temporarily get more fuel to the bottom end,
If you get any positive information, then thank Fernando.... he gave me these tips.
08-28-2007, 05:16 PM #4
ill try to come up with something cause i dont have chokeplates or flame arresters
08-28-2007, 09:44 PM #5
Quick question... did you have your powervalve cables off at any time..??
This sounds like what i had/did recently..
I'd put the damn cables on in reverse.....!!!!!
So before you start on making choke plates outta tape check the cables..
08-28-2007, 10:04 PM #6
I Have The Same Problem!!!! I Thought It Was The 14/20 Prop I Have On It.
08-28-2007, 10:57 PM #7
Like I said before george you sound rich to me 1/8 turn at a time
08-28-2007, 11:43 PM #8
No F/A's at all? or are you running the stock air box? The carbs need some restriction to help with signal.
08-29-2007, 05:50 AM #9
Thats the same jetting I ran on my 1200 including turns out on the screws. What flame arrestors do you have? How did you seal the VF-3's up? I would be suspicious of an air leak.
You need gaskets on both sides of the VF-3's with sealer. I cut gaskets and use 3Bond 1211 smeared thin on the gasket surfaces.
08-29-2007, 03:58 PM #10
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