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Old 11-25-2007, 07:00 PM   #1
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Default Idle Tuning

I'm breaking in my Firestorm now. It won't idle low enough.

The idle stop, is set to be 1mm open, as per the manual.
However I have to have it trimmed a little bit more open (2mm) to keep it running. If I trim it down to where it's on the idle stop, it stalls.

So, because of the trimming, it revs too high and moves when it should be idling.

So, what do I have to adjust? I can't close the idle stop anymore?...so?

Thanks!
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Old 11-25-2007, 07:19 PM   #2
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So, I think this is a Low-Speed needle issue.
Only thing, is it too Rich or too Lean?

The carb needs to be kept open more than it should (more air) to keep running.

Lean or Richen the Low-speed?
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Old 11-25-2007, 07:26 PM   #3
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Here ya go man use the Houston tuning method. He is a great guy/racer and knows his you know what.


.21 engine tuning 101 ;
do the pinch test about 2-3 inches from the carb fuel intake , should take about 3 seconds for the engine to idle up if the low needle is set properly . adjust the idle as low as it will allow you to and still stay running after reving out the engine and it comes back down to idle . after you get the perfect tune richen up the lsn 2 hours and idle up about 1/4 turn to stop engine from flaming when race conditions are applied . when adjusting the high speed , start off very rich but runnable , lean out to desired temp and feel , watch for good smoking for at least 6 feet and pay attention to the engine , if it starts to lose power on the bottom , you either have the wrong clutch/pipe combo or if there is no smoke it is a lean bog (dangerous) stop running it on the track , bring it in and richen the low speed at least 6 hours and the high needle at least 3 hours and start over .REMEMBER WHEN TUNING : FUEL MAKES POWER , NOT AIR !!!!!!
happy tuning bro ,
monty
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Old 11-25-2007, 07:27 PM   #4
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Default Idle tuning

One piece of advice, Use the idle screw to adjust the idle. Don't use your trim to adjust the idle on your car because when you apply the brakes you will go below idel level and the car will just shut off. Start with that and if that does not cure the problem you may have to lean out the low speed circut located at the linkage end of your carb. Turn it clockwise in one hour increments. And Check to see if it is too lean by pinching off your fuel line. It should not rev up too much before it die's, if it does you you may still be to rich. This should help.
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Old 11-25-2007, 09:24 PM   #5
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Thanks for the tips. I just had to lean the Low-speed a bit and now it idles fine.

This thing is a blast!
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Old 01-05-2008, 03:39 PM   #6
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Not to bring back an old thread but I just got my Firestorm today and I am having problems with it. I was able to do the break-in according to the instructions. Once that was done I started to mess with the high speed needle. I didn't really see any improvements with any of the changes, so I set it back to factory settings. I have NOT touched the low speed needle.

With that being said, I tried to adjust the idle with both the trim and the idle screw. With using just the trim, the car would bog down at WOT and stall. Prior to this, if I hit the brakes, it would stall the car, regardless. I found this post and saw the part about using the idle screw, so I went and messed with the idle screw. When I got the car restarted, it seemed to be running at 3/4 throttle for idle. I adjusted the screw in and out and there was NO change to the idle. The tires were still spinning and the car still seemed to be idling at 3/4 throttle (car is up off the wheels.) Now I can't even get the car to start. I have the high speed needle back to factory settings, the low speed needle has not been touched, and I believe the idle screw is back to factory setting (I think.) I have even changed out the glow plug and checked to make sure the glow starter is working. The trim is where I originally had it during break-in.

I am at a loss here on what to do. Any of you guys with Firestorms that have any suggestions, I am open to them. I had a great time driving this earlier, but I am getting pretty frustrated now. In my eyes, everything is back to factory settings, but I could be forgetting something.

Thanks
Chris
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Old 01-05-2008, 06:11 PM   #7
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Hey,

-Make sure your High and Low speed needles are reset back to stock (flush).
-Set your Idle stop, so the carb is open 1mm, when the throttle is closed.
-Set your throttle trim, so when the trigger is neutral, the carb will be on the idle stop (1mm open). [You may need to open the trim a bit for starting]

From here Lean the low speed. The G3.0 is set soooo rich, even for breakin.
You'll probably need to turn it at least a half turn, to get it to sit still with the idle at 1mm open.

Then work on the high speed......
That should help Let me know how it goes.
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Old 01-05-2008, 07:04 PM   #8
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Ok I went back out in the garage and messed with it some more. I was able to get it started, and the idle was reasonable, but the wheels were still spinning. The only problem is I don't know how to adjust the carb. I have attached 4 pictures to show what I see if that helps anybody. The Idle Screw seems to control the front to back not the side to side. The picture in the manual doesn't show any gap in the back half, where as mine has it (first picture.) It also shows the brass pieces touching each other in the manual, mine don't touch (second picture.) I know this seems kind of vague, but I am hoping it makes sense.







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Old 01-06-2008, 08:04 AM   #9
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looks like theres somehing loose on the carb. fiddle with the bolts on the barrel and see if that makes a difference.
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Old 01-06-2008, 10:09 AM   #10
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The pictures aren't great. Is that an actual gap on the left side or is that a shadow? You shouldn't have any gap on the sides of the carb.

Make sure that golden nut on the carb is tight. Its hard to tell from the pic.
Has it always been like that? or did it happen after a crash?

If it came from the factory like that, you should call HPI.

The needles your talking about move in and out when you close/open the carb.
Your low speed needle controls that. You don't really want them to touch.
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Old 01-06-2008, 10:15 AM   #11
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Thats an actual gap on the left side of the carb. As far as I know it has always been like that. The only "crash" I have had with this car is jumping from my sloped curb to my garss (about 6' worth of distance) and landing on the nose and flipping over. That wasn't even really going that fast. I can try to get some better pictures. Just hard to do with a flash to get any kind of light in there. I will check the golden nut to make sure it's tight.

Thanks for the replys so far.

Chris
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Old 01-06-2008, 10:42 AM   #12
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Old 01-06-2008, 10:47 AM   #13
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Quote:
Originally Posted by rltanner View Post
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Old 01-06-2008, 12:17 PM   #14
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Ok so I went out and put everything back together. Started the car with about 1/2 a tank and ran it. Seemed pretty sluggish but ran good for the most part. Once that tank was almost empty the car was running pretty good. Temp outside is roughly 63* with about 15mph winds. Brought the car in, filled the tank and started it. As soon as I went WOT with it, the car took off, blowing some smoke and then fell flat on its face, stalling out about 2 seconds into it. Car hasn't started back up since and I just left it alone.

I really enjoy this while its running, but don't want to get frustrated with it so I just leave it for a while. I bought it as a toy for me to play around with and to have my 2 sons (4 an 1.5 yrs old) have a good time watching.

Chris
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Old 01-06-2008, 12:22 PM   #15
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Quote:
Originally Posted by Woof View Post
Is that an actual gap on the left side or is that a shadow? You shouldn't have any gap on the sides of the carb.
Isn't that what the book says should be 1mm? The part I have circled right here...

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