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need help tuning 3.3

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galph

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This hobbie is not as easy as it looks like. i have a revo 3.3 and i can't tuned that thing if my life depended on it! the high speed needle is four counter clock-wise turns! the low speed needle needs to be set to the thickness of a credit card! and the acceleration i have no freaking idea! maybe I'm doing all the needles wrong! i just can't get the right acceleration! just came back inside because brown liquid was coming out of my exhaust! is that bad? what do you recommend on the needles set and the acceleration! how many counter clockwise turns on the acceleration needle! please help before i destroy my truck! thanks!
 
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Brown liquid out the exhaust? I am assuming you mean that you had raw fuel coming out the exhaust. If that is the case you are way too rich.

Have you set your LSN according to the instructions (1mm opening)?

What specifically do you mean by "the acceleration needle"?
 
okay the hsn is four counter clockwise! and lsn is to 1mm opening! and the idle is how many counter clockwise turns? how many counter turns do you recommend on the hsn and the idle needle? thanks
 
I can not recommend general setting for either. This is where you tune for YOUR conditions. All I can say thus far is the LSN is in the general area if you are at 1mm on the carb opening. Your HSN appears to be rich based on your comment about "brown liquid".

You generally set the idle screw to a place where your truck will idle without dying but isn't screaming at idle nor trying to run away from you.

Are you still in the break-in process? If so I would suggest that you lean the HSN out until you have a nice, steady stream of blue smoke under acceleration. You don't want to lean it out too far at this point.
 
Just for reference, you have your terms mixed up. The idle needle is where you set your idle gap (~1mm), the LSN is on the slide collar. See https://www.rcnitrotalk.com/gallery/data/500/Carb.jpg for reference. The idle needle is on the other side of that pic. Usually has a spring on the needle too keep it set in place.

Take a look at the manual which is actually fairly thorough.
 
so what's the word? you get it figured out? Nothing beats a little trial and error.

Also be careful at using outside visual reference as a tuning indicator. Sure works as a decent return point if you really get it out of whack but since there are tolerance differences in the needles and seats then there will be differences in positions as well. If you try using the traxxas tuning procedures they don't exactly seem clear to first time tuners but will help. Taking the time to read over all the others' questions in this forum and seeing the recommended solutions to their tuning problems really helped me. Inevitably had I just asked one specific question I got one specific answer which only helped me get to my next problem quicker. Keep working at it, you'll be a tuning pro in no time. Another recommendation. Get a temp indicator of some sort. I heard it before and disregarded it until I tried it and am a firm believer. Trying to pic up on audible changes in these engines fine tuning is much more difficult than on a larger engine. Temp will indicate results of fine adjustment that you will not.
 
so if temps are running to high do i lean or richen? also when i go at high speeds then let go of the throttle my engine will make a high purring noise then goes away! is that not good? thanks

oh yea, what kind of temp gun do you guys recommend! thanks again
 
if you are running too lean, it will cut out under power...that doesn't necessarily mean that by it not cutting out that you are NOT too lean and running hot...you may be shortening the life of your motor unknowingly.

If it's hot or too lean, you'll want to richen it up...HSN counter clockwise. I'm no expert on temp guns but there is a lot of advise throughout the gen nitro talk forum. I use on board because it's easy and i only have one car. Read up and decide what's best suited to your use and budget.
 
Amoeba said:
Just for reference, you have your terms mixed up. The idle needle is where you set your idle gap (~1mm), the LSN is on the slide collar. See https://www.rcnitrotalk.com/gallery/data/500/Carb.jpg for reference. The idle needle is on the other side of that pic. Usually has a spring on the needle too keep it set in place.

Take a look at the manual which is actually fairly thorough.
Click to expand...

All I can add to this is READ READ READ! Tuning is a pain and we've all been there. We can not tell you an ideal number of turns in or out to give you optimal power. Amoeba recently purchased a rig of mine and the settings were way rich for where he lives when they were fine for my area. One persons settings are going to vary from anothers living even on the other side of the state let alone the country and even more so another country. So read the charts and have patience. You'll get it.
https://www.rcnitrotalk.com/forum/showthread.php?t=60832
Allways make sure to warm it up to running temps before you start tuning and tune the HSN first.
 
galph said:
so if temps are running to high do i lean or richen? also when i go at high speeds then let go of the throttle my engine will make a high purring noise then goes away! is that not good? thanks

oh yea, what kind of temp gun do you guys recommend! thanks again
Click to expand...

The high purring noise is a lean bog of sorts when you let off. It means you're too lean on the LSN. The traxxas book is really quite good at explaining this. It gives you a garden house and nozzle analogy that is great.
 

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