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sluggish bottom end

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liftedcj7on44s

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Location
Fayetteville, N.C.
RC Driving Style
  1. Bashing
  2. Racing
Ok i switched fuels today. I was running blue thunder 20%, I had the tune just about perfect. Well i switched to o'donnels 20%. I tried tuning it in. I finally got the HSN set pretty much perfect just need to check with a temp gun. But on the Low speed i can't get the sluggishness out of it. It does not bog down any its just sluggish. What do i need to do lean the LSN out more?
 
leaning out the LSN should help just don't lean it out too much just make sure you make a couple of high speed runs to clear out the fuel
 
give it a shot. . .and if nothing else . . .put it back to the factory settings start again, its worth the extra time if you don't wanna lock up ur mill
 
Could be your lsn but I remember you asking about gearing and a few other questions. Basically I would like to know your gearing and current set-up. Because depending how your geared that just might be your pull out and no tuning in the world will change it.
 
LSN but dont go to far
my 1:10 use to do this and i actually had to richen it :S a whole 4.5 turns from factory
 
last night i moved the pincher on the line closer to the carb. so today i can use it to do the pinch test. Tomorrow i will have a temp gun again to tell if I'm going in the right direction. I had the motor tuned great around the 240 range.
 
Just went out and tried to get the LSN needle set. But i am observing something. When the engine is cold the bottom end punch is great. Meaning the longer i run the truck the worse the bottom end gets. The midrange to top end stays the same and screams really well. Now correct me if i am wrong but as the engine temps rise(more heat) i need more fuel correct? I did the pinch test and the engine died in about 3 seconds but it didnt rev up.
 
ya i bet its your lsn because thats what was wrong with mine. i also run 20% O'Donnell Fuel.

edit: sorry didnt see your last post there.
 
liftedcj7on44s said:
just went out and tried to get the lsn needle set. But i am observing something. When the engine is cold the bottom end punch is great. Meaning the longer i run the truck the worse the bottom end gets. The midrange to top end stays the same and screams really well. Now correct me if i am wrong but as the engine temps rise(more heat) i need more fuel correct? I did the pinch test and the engine died in about 3 seconds but it didnt rev up.
Click to expand...

correct

solly69 said:
LSN but dont go to far
my 1:10 use to do this and i actually had to richen it a whole 4.5 turns from factory
Click to expand...

back to what i said before
 
I am getting ready to go to the local track here. I'm going to wait til mid afternoon so outside temps will be higher and tune it some more then. I will report back later this afternoon.
 
start the LSN as toy normally would richen it up in 1/8 increments remember to do a lap to clean out built up fuel in the engine
 
I always run 2 or 3 high speed runs before i adjust anything. My backyard is about a football field long so i make sure i wind it out pretty good.
 
Ok I want you to try something fill up on fuel warm it up and fill it up again. Now run it keeping a eye on fuel level, when it starts to get boggy, mark the tank. Fill it up and see if the bog is gone. Do not allow any cool down during this. if the bog comes back at the same point, it could be 2 things:

1. All cars tend to get leaner as your tank gets lower. Solution (richen it!) is to tune your car at half tank of fuel now when full you will be slightly rich and right on as your fuel level drops. If this doesn't help see number 2.

2. internal air leak in the tank. Replace fuel tank.
 
I have already been tuning at half a tank. Anyway i reset everything back to factory settings. I had to eventually richen the LSN and then went back just a hair and the low end grunt seems to be alot better.
I have said this a million times that i hate electric but i am honestly thinking about getting a ERBE!!:D

O almost forgot to mention. I am running a Traxxas "hot" glow plug. can't remember the number right off the top of my head though. Would changing to a colder plug yield better results? I dont know how this 3.3 is supposed to respond but on bottom end it doesn't pick up fast enough. Like its just sluggish. I was hoping that from a dead stop and punching it i should get instantaneous pick up with no sluggishness. Nothing is binding up either. I've checked everything to make sure and the clutch and all is good.
 
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Ok is the engine sounding boggy or is the take off just sluggish. I am wondering if you might need to tighten your slipper clutch a bit or if its time for a new clutch.
 
It does not bog like a overly lean condition. Its just sluggish. I got alot of it out but still not all of it. The truck is only about 3 weeks old so the clutch should not be wore out. If the slipper clutch were wore out i would imagine the motor would race faster but the take off would be slower. It acts just like the clutch shoe spring came apart and the clutch is engaged all the time. So when i do a standing start it does not build revs fast enough. But this is not the case. I can roll the truck backwards really fast and stop real quick and watch the spur gear and the clutch bell spin all day long.
Maybe i am over explaining myself.
Ok i fire the truck up, i make a few passes around the back yard to get temps higher. I then start driving the truck hard. At this point the bottom end is really really punchy and its hard to keep the front end down, at the same time the top end is not winding out. So as the temps start to raise more the top end comes in and it shifts to second like it should with great speed and pick up. Now the bottom end has fallen off some. if i keep driving the truck wide open the bottom end never comes back. Now if i slow down for a bit and let the engine cool off some then the bottom end starts to come back somewhat but the top end stays punchy and fast.
Another question i have is this which concerns me. I clean my truck with compressed air everyday. The next day i fill up with fuel( I always run the tank dry) and when i fill up i make sure that i dont spill any fuel on the fuel tank. After the first tank runs out all the grass and dirt is now stuck to the top of the tank leading me to believe that the tank maybe leaking from the oring causing fuel to slosh out while I'm driving. If the tank were dry outside nothing should stick to it.
 
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i am not to sure on the tuning part but as far as everything sticking to it mine always has the dirt and sometime grass just like you i blow it down and clean it constantly. the reason it all sticks to mine i have found is from the oil in the fuel coats the back of mine and then everything sticks to it. especially the rear a arms and body.
 

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