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Another quick question about A Tune

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Old 10-18-2014, 07:13 AM
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darek_u
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Default Another quick question about A Tune

Today I dynoed my car in 100% stock setup except for A-Tune installed instead of factory chip. The result was 247 HP at the crank and 350 Nm. The only difference was rpm cut out at 6900 instead of 6500 and quicker boost build (500 rpm lower for full power). Does A-Tune add and HP/Nm over stock? Or I just have perfectly rebuild engine to stock parameters with upgraded engine management ?
Old 10-18-2014, 11:01 AM
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refresh951
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A Tune by itself most likely adds very little PEAK HP at 250 crank but compare area under the curve. The A Tune is all about responsiveness. Your result of 247 HP is very subjective when taking it back to the crank. I also would be very careful over revving to 6900 rpm. You wont see any more power after about 6K so IMO it is just a high risk, no reward event. Can you post the dyno?
Old 10-18-2014, 04:18 PM
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fejjj
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According to the engine builders I have spoken too, the majority of major engine problems occur when they are revved above 6k.

Like Shawn said, you are not going to see much if any more power above 6k anyway.

Sounds cool until it goes boom!
Old 10-19-2014, 01:19 PM
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darek_u
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No more revving above 6krpm, thanks for that, the dyno guy should know about it...
Here comes the picture. Peak 247 hp @ 5513 rpm, peak tq 349 Nm @ 4029 rpm
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Old 10-19-2014, 03:44 PM
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Is that at the rear wheels?
Old 10-19-2014, 07:22 PM
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calculated at the crank.
Old 10-19-2014, 10:05 PM
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Stock KLR chip with stock boost management?
Old 10-20-2014, 02:05 AM
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stock KLR software
Old 10-20-2014, 11:12 AM
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Then that's not bad.

Where you'll see the gain with the A-Tune is right where Shawn said - it's the area under the curve. You should have much more power at part throttle and more power in the mid-range, off-boost, and as the boost is coming on. Once you're at WOT and full boost there isn't all that much left in the tune to tweak. Maybe a little more spark advance, maybe a little leaner on the mixture, but it's not going to be huge.

The improved mid-range and part-throttle driveability should be immediately noticeable.

Did you dyno before and after? If so, let's see the overlay, new vs old. Every car is a little different. Comparing your dyno numbers to the factory-advertised specs isn't really the best way to see the gain it got you.
Old 10-21-2014, 04:32 AM
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darek_u
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I can see and feel the difference. Exactly as you stated above - PT is much better and overall "feeling" of the car has improved. No doubt about it. I was just wondering if A-Tune adds some power or just brings 951 closer to modern cars. I'm happy with what I gained, there are other ways for getting more HP.
Unfortunately I cannot compare stock chip vs. A-Tune. My car has always been chipped, I just replaced KLR software with stock one. I have old dyno and A-Tune on one graph, it is little higher (20 HP more) but curve looks similar. I don't know if this comparison makes a lot of sense as I don't know the origin of the tune (bought it with the car). I may swap the computers next year and dyno the car with stock software, just to compare and post the results.
Old 10-21-2014, 10:53 AM
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"I may swap the computers next year and dyno the car with stock software, just to compare and post results."


I wouldn't bother going to to the trouble of doing that.

Just drive your car and enjoy your A tune!
Old 10-21-2014, 01:21 PM
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Originally Posted by darek_u
I can see and feel the difference. Exactly as you stated above - PT is much better and overall "feeling" of the car has improved. No doubt about it. I was just wondering if A-Tune adds some power or just brings 951 closer to modern cars. I'm happy with what I gained, there are other ways for getting more HP.
Unfortunately I cannot compare stock chip vs. A-Tune. My car has always been chipped, I just replaced KLR software with stock one. I have old dyno and A-Tune on one graph, it is little higher (20 HP more) but curve looks similar. I don't know if this comparison makes a lot of sense as I don't know the origin of the tune (bought it with the car). I may swap the computers next year and dyno the car with stock software, just to compare and post the results.
You can always put the other KLR chip back in it. Should run just fine + more power due to the increased boost from the other KLR chip.



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