Superchips Flashpaq for JK, Initial Impressions
JK Enthusiast
Joined: Jul 2008
Posts: 135
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From: Sharjah, UAE
for quick tune and worth the 300 bucks
JK Enthusiast
Joined: Nov 2009
Posts: 466
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From: Washington D.C.
I wish they'd hurry up with the 2010 update already... my entire list of mods is on hold until they do.
Thread Starter
JK Junkie
Joined: Jul 2008
Posts: 3,017
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From: Lakewood, OH
There are however some variables that will somewhat change the equation. At closer to sea level, the PCM and knock sensors might afford you enough advance to run 89 Octane and have better performance. At high altitude, even the 87 octane may be too much with the thin air, and 85 Octane would be the call.
With a programmer, you have the benefit of changing the timing so various Octanes will work. Some of course will work better than others. On the Flashpaq this is all done behind the scenes with just a simple selection of the Octane rated tune you wish to use.
JK Freak
Joined: Oct 2008
Posts: 860
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From: Andalusia, Alabama
Just got my superchip from Northridge today. Got her updated and tuned the Jeep to 87. Run it down the road a mile or so and there did seem to be noticeable pickup in power. Still won't win any races but you can tell there is a change.
JK Enthusiast
Joined: Aug 2009
Posts: 244
Likes: 0
From: Springdale, Arkansas
[QUOTE=JPop;1553755]A stock JK is designed to take 87 Octane. Higher Octane fuel doesn't mean it contains more power, it just burns slower. The widely held myth is that higher Octane fuel will make your vehicle run better, but what it actually does is leave unburnt fuel in the exhaust, raising emission levels and hurting performance.QUOTE]
Great explanation of the octane rating and would be true if you were driving your engine at the top of its power band - probably around 3500 RPM. But since you are actually driving closer to 2000 RPM the majority of the time, you might need your gas to burn a little slower. Higher octane fuel has more carbon-carbon bonds per molecule of fuel and will have more potential energy. You are right that you won't get any more power if you are just dumping unburnt fuel into your exhaust. But at low RPM's, you might be burning all the fuel in the cylinder before the piston is completely down. You should see the benefit of the higher octane gas when driving highway speeds and relatively low RPM's. When you are driving trails (or even around town for a lot of us with lead feet!) there won't be any advantage.
Great explanation of the octane rating and would be true if you were driving your engine at the top of its power band - probably around 3500 RPM. But since you are actually driving closer to 2000 RPM the majority of the time, you might need your gas to burn a little slower. Higher octane fuel has more carbon-carbon bonds per molecule of fuel and will have more potential energy. You are right that you won't get any more power if you are just dumping unburnt fuel into your exhaust. But at low RPM's, you might be burning all the fuel in the cylinder before the piston is completely down. You should see the benefit of the higher octane gas when driving highway speeds and relatively low RPM's. When you are driving trails (or even around town for a lot of us with lead feet!) there won't be any advantage.
JK Freak
Joined: Oct 2008
Posts: 860
Likes: 0
From: Andalusia, Alabama
[QUOTE=drschem;1556428]
As fare as I can tell you both said the same thing just you said the first guy to say it was wrong? You added a detail Jpop skipped but it seems irrelevant.
The point is timing of the compression vs. rate of combustion in the stock tune is designed for 87 octane. A programer changes these ratios depending on the tune you choose. I've tried 91 and 93 and saw decreased fuel economy with the stock tune. So this seems to make since, I'm 100% in town and off road no highway.
I don't mean this as a contradiction or complaint I'm just stating how I understand the situation. Correct me if I'm wrong.
A stock JK is designed to take 87 Octane. Higher Octane fuel doesn't mean it contains more power, it just burns slower. The widely held myth is that higher Octane fuel will make your vehicle run better, but what it actually does is leave unburnt fuel in the exhaust, raising emission levels and hurting performance.QUOTE]
Great explanation of the octane rating and would be true if you were driving your engine at the top of its power band - probably around 3500 RPM. But since you are actually driving closer to 2000 RPM the majority of the time, you might need your gas to burn a little slower. Higher octane fuel has more carbon-carbon bonds per molecule of fuel and will have more potential energy. You are right that you won't get any more power if you are just dumping unburnt fuel into your exhaust. But at low RPM's, you might be burning all the fuel in the cylinder before the piston is completely down. You should see the benefit of the higher octane gas when driving highway speeds and relatively low RPM's. When you are driving trails (or even around town for a lot of us with lead feet!) there won't be any advantage.
Great explanation of the octane rating and would be true if you were driving your engine at the top of its power band - probably around 3500 RPM. But since you are actually driving closer to 2000 RPM the majority of the time, you might need your gas to burn a little slower. Higher octane fuel has more carbon-carbon bonds per molecule of fuel and will have more potential energy. You are right that you won't get any more power if you are just dumping unburnt fuel into your exhaust. But at low RPM's, you might be burning all the fuel in the cylinder before the piston is completely down. You should see the benefit of the higher octane gas when driving highway speeds and relatively low RPM's. When you are driving trails (or even around town for a lot of us with lead feet!) there won't be any advantage.
As fare as I can tell you both said the same thing just you said the first guy to say it was wrong? You added a detail Jpop skipped but it seems irrelevant.
The point is timing of the compression vs. rate of combustion in the stock tune is designed for 87 octane. A programer changes these ratios depending on the tune you choose. I've tried 91 and 93 and saw decreased fuel economy with the stock tune. So this seems to make since, I'm 100% in town and off road no highway.
I don't mean this as a contradiction or complaint I'm just stating how I understand the situation. Correct me if I'm wrong.
JK Enthusiast
Joined: Aug 2009
Posts: 244
Likes: 0
From: Springdale, Arkansas
nikbass
You're right. I'm just suffering from a little posting diarrhea!! I guess I was just trying to say that higher octane gas does have more power, you just have to know when you can use it or you would be waisting money to buy it. For those of us without a flash pack, it is driving habits that dictate when you might use high octane gas. For what it's worth, I do most my highway driving in a Yucon Denali (6.1L) and the added advantage in fuel mileage from higher octane gas is about equal to the higher cost so I usually don't bother. I can't drive a whole tank out without stopping anyway!
You're right. I'm just suffering from a little posting diarrhea!! I guess I was just trying to say that higher octane gas does have more power, you just have to know when you can use it or you would be waisting money to buy it. For those of us without a flash pack, it is driving habits that dictate when you might use high octane gas. For what it's worth, I do most my highway driving in a Yucon Denali (6.1L) and the added advantage in fuel mileage from higher octane gas is about equal to the higher cost so I usually don't bother. I can't drive a whole tank out without stopping anyway!