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Old 01-13-2008, 02:29 PM
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Originally Posted by Mpowerz
Thank you...

Will the temps rise rear the end of the tank when it becomes empty?
Yep the temps will rise a bit as the fuel tank empties.
Sounds to me your tune is good and you should just leave it and have fun now. Just remember if you're not racing you really don't need a race tune, and your engine will last much longer this way.

As for a target number for your temp range 220-230 is a nice number to shoot for. But if you are happy with the performance it's giving at the temps you just stated then there is nothing wrong with running it their either.
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Old 01-13-2008, 06:24 PM
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Originally Posted by jbrow1
Yep the temps will rise a bit as the fuel tank empties.
Sounds to me your tune is good and you should just leave it and have fun now. Just remember if you're not racing you really don't need a race tune, and your engine will last much longer this way.

As for a target number for your temp range 220-230 is a nice number to shoot for. But if you are happy with the performance it's giving at the temps you just stated then there is nothing wrong with running it their either.

Will a race tune burn more or less fuel? It might be a dumb question.. Is the motor running more effecient= more mileage
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Old 01-13-2008, 07:08 PM
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Correct. The leaner you have it running the less fuel it's burning.
Also getting less oil which is what cools and lubricates the engine.

Although if you tune it to powerful and wheelspin everywhere you'll be wasting more fuel than you are saving.
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Old 01-13-2008, 07:27 PM
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Originally Posted by jbrow1

Although if you tune it to powerful and wheelspin everywhere you'll be wasting more fuel than you are saving.

Very good point.. Thank you...
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Old 01-14-2008, 08:59 AM
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Originally Posted by Mpowerz
The motor would idle up slightly around 4-5 seconds before wanting to cut out.. Should the LSN be leaned out a 1-2 hours?
Is this idle behavior happening during the pinch test, or after you drive down the straightaway and bring the car to a stop?
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Old 01-14-2008, 10:08 AM
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Originally Posted by SkarTisu
Is this idle behavior happening during the pinch test, or after you drive down the straightaway and bring the car to a stop?

It is happening when I pinch the line...... If it were idling up after a straightaway what would be the casue and corection?

Thanks
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Old 01-14-2008, 10:33 AM
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Since it's happening when you're pinching the line, then you should be good. If it were happening after the straightaway, then your LSN is probably too rich.

Don't worry about the 240-260 temps either. You said you're getting a smoke trail. Most of the Italian based engines like to run those temps, especially during break in. Start to be concerned when you get above 290.
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Old 01-14-2008, 01:03 PM
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Originally Posted by SkarTisu
Since it's happening when you're pinching the line, then you should be good. If it were happening after the straightaway, then your LSN is probably too rich.

Don't worry about the 240-260 temps either. You said you're getting a smoke trail. Most of the Italian based engines like to run those temps, especially during break in. Start to be concerned when you get above 290.

Thank you for the info. What about cheap motors like the Mach .26 what temps should they be running?


So if the RPM are hanging for a bit the LSN is TOO rich?


Also does 30% have more cooling ability then 20%?
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Old 01-14-2008, 02:21 PM
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Originally Posted by Mpowerz
Thank you for the info. What about cheap motors like the Mach .26 what temps should they be running?
I've never run one and haven't heard much info on them, but my guess is they'll run warm too. As long as you're getting a smoke trail and not four stroking you're good. With tuning experience you can (and should) throw away the temp gun on a given engine and tune by performance only.

So if the RPM are hanging for a bit the LSN is TOO rich?
That's been my experience. The pinch test tends to give you a LSN setting that's on the fat side from what I've seen.

Also does 30% have more cooling ability then 20%?

I don't know the answer to this one. I think you're right? I've never looked into it.

The following site has information written by the late Ron Paris. He was one of the best engine guys in history. I started using his techniques recently and my tune has noticeably improved.

http://www.nitrohouse.com/tech_tips.htm
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Old 01-15-2008, 11:00 PM
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Guys please have a look at the burn patterns on the piston and let me know what you think about the tune.



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Old 01-16-2008, 08:20 AM
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Looks fine to me. What does the glow plug look like?
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Old 01-16-2008, 08:49 AM
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Hmmmm... sounds like you are close, but maybe lean on the bottom still.

If you pinch the line and it dies IMMEDIATELY it is too lean. (LSN)

If the idle climbs as it sits it is probably too lean. (LSN)

If it idles more than 8-10 seconds without loading up and the idle slowing down it is probably too lean (LSN)

If you have lots of smoke under acceleration, but still good power, the HSN is probably about right, or maybe even a touch too rich.

Being too lean on either end will bring your temps up. One setting affects the other to a certain extent.

Temperature is just a ballpark figure. Tune the motor so it runs right and so the temps don't get excessively high.
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Old 01-16-2008, 12:18 PM
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Originally Posted by DOMIT
1. If you pinch the line and it dies IMMEDIATELY it is too lean. (LSN)

2. If the idle climbs as it sits it is probably too lean. (LSN)

3. If it idles more than 8-10 seconds without loading up and the idle slowing down it is probably too lean (LSN)

4. If you have lots of smoke under acceleration, but still good power, the HSN is probably about right, or maybe even a touch too rich.

5. Being too lean on either end will bring your temps up. One setting affects the other to a certain extent.

6. Temperature is just a ballpark figure. Tune the motor so it runs right and so the temps don't get excessively high.

Does #2 & #3 refer to the pinch test or is it for just when the motor is at idle?
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Old 01-16-2008, 12:36 PM
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Originally Posted by Mpowerz
Does #2 & #3 refer to the pinch test or is it for just when the motor is at idle?
Just at idle.
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