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XJers with the Superchips Flashpaq 3875 Tuner

G

Ghetto2315

NAXJA Forum User
Location
Rumson, NJ
I searched and it doesn't seem many XJers have this.

Recieved mine in the mail today and eager to start tuning my XJ. I alredy use premium fuel in my XJ so I'll be running the 91-Octane Performance setting.

Just wanted to know what you did for the following:

Rev Limiter (I'm assuming you just did the highest limit possible?)
Cooling Fan (What temp did you have yours kick on at?)
Real Time Idle-up?

I'm eager to get this done soon.

Thank you guys!

EDIT: The troubleshoot section states that this Flashpaq will work with "short or normal tube headers". Any of you running headers and running lean? The Superchips Tech said I may run in to this problem with my Banks Header.
 
Rev limited won't do anything for you if you have an auto. Cooing fan... depends what temp your normally run at. I would set it a bit cooler than stock kick on. Not sure about idle up... maybe idle increase?

Haven't seen you in a while here.
 
Hey B, dunno if I told you yet or not, but I did get that PSC1-002(that I soaked) back from split-sec. They were unable to read from it like I was, but they then wrote to it and it cleared it right up. I'm not using it at the moment, and I still haven't gotten the Unichip custom tuned(need the funds for the m3). I take it you're still weighing the options?
 
Lemme know how it works..... Just sunk $275 into a K&N FIPK for my 00 Sport 4.0L, to gain 7.8hp (according to K&N's included dyno sheets)... so $320 for 28hp (advertised) seems like a steal.
 
One other option is to talk to [email protected] for a performance flash for the PCM. This is what was done to mine:

Increased speed limited from 114 mph to 254 mph (a bit optimistic there)
Pushed the rev limited from 5300 to 6000 RPM
Increased the idle from 648 to 700 rpm
Turned the torque management off
Turned stall torque off (don't know what the heck that is)
Adjusted fuel map
Something about Cylinder misfire code mil only to off
Ac compressor kicks off for 10 seconds at WOT )didn't even know they could program that, but neat)
Set cruise control range 30mph-130mph

IIRC it was around $300.
 
Talyn said:
One other option is to talk to [email protected] for a performance flash for the PCM. This is what was done to mine:

Increased speed limited from 114 mph to 254 mph (a bit optimistic there)
Pushed the rev limited from 5300 to 6000 RPM
Increased the idle from 648 to 700 rpm
Turned the torque management off
Turned stall torque off (don't know what the heck that is)
Adjusted fuel map
Something about Cylinder misfire code mil only to off
Ac compressor kicks off for 10 seconds at WOT )didn't even know they could program that, but neat)
Set cruise control range 30mph-130mph

IIRC it was around $300.
Click to expand...

Sounds like a good deal for a custom tune. Hows the seat of the pants feel with it installed? Any dyno results?
 
No dyno numbers and I can't say how it felt because my XJ was down for a bit due to engine changes. However shift quality has improved due to the torque management elimination. I needed the fuel map adjustments to match the injectors to my engine and that has worked pretty well. I also like the AC compressor kicking off at WOT for 10 seconds. The efan coming on earlier is nice too.
 
I just don't understand why the hell my XJ idles at 800-900 (indicated) rpm. Seems that being an time proven (some of you would say 'ancient') design, it'd idle at 650-750rpm.

My Honda "econobeater" idles at 6-700rpm. And that thing loves to rev. I just don't get it.
 
imteresting thread to resurrect...


the 4.0 has a much heavier rotating mass than your honda. usually you want to set it up so it will idle at the lowest rpm range to keep the mass rotating without losing momentum or struggling to remain running.
 
Talyn said:
What does a idle speed have to do with a high revving engine? One has nothing to do with the other.
Click to expand...

yes, but what I'm getting at is a lot of old engines (the 4.0 design roots go back to 1962) have idle spec'd as low as 650-750 rpm, as the heavier parts help carry the momentum so it'll idle at that speed without any roughness/running out of momentum.

Newer engines, such as the honda I have, has aluminum block (not that it matters here), rods and pistons (a lot lighter than steel), and a steel crank. So obviously the Jeep has a heavier rotating assembly, and therefore it carries more inertia at any engine speed.

So, already, you'd think the Jeep would be able to idle at rpm lower than 900.

Now consider cylinder count. The Honda only has 4, the Jeep has 6. So, in the 720 degrees of rotation it takes to do the complete intake-compression-power-exhaust cycle, the Jeep has less time in between cylinder firings. (720/6= jeep and 720/4= honda. The smaller the number the smaller the time between a cylinder firing)

The only reason I can think of that the Jeeps idle at 900-950rpm is emissions or they under-spec'd the alternator and need that to spin faster to keep up with electrical loads.
 
ChevelleSSLS6 said:
The only reason I can think of that the Jeeps idle at 900-950rpm is emissions or they under-spec'd the alternator and need that to spin faster to keep up with electrical loads.
Click to expand...
this could be accomplished by changing the size of the pulley, I doubt it has anything to do with the idle speed.
 
Your honda does not have aluminum rods. Idle speed is determined by many factors such as water pump speed, alternator speed, power steering pump speed, emissions, splash oiling, camshaft timing events and NVH. You also need to take in to consideration all the extra drag created by the piston rings, flat tappet cam, heavy valve train etc. Per the 95 and 99 FSM the idles speed should be 600 rpm. However, the only place I could find a reference to the idle speed was in the engine spec section for oil pressure.
 
Talyn said:
Your honda does not have aluminum rods. Idle speed is determined by many factors such as water pump speed, alternator speed, power steering pump speed, emissions, splash oiling, camshaft timing events and NVH. You also need to take in to consideration all the extra drag created by the piston rings, flat tappet cam, heavy valve train etc. Per the 95 and 99 FSM the idles speed should be 600 rpm. However, the only place I could find a reference to the idle speed was in the engine spec section for oil pressure.
Click to expand...


Hmmm... I should see if the tach is reading accurately. Any suggestions without getting one of those wireless/laser tachs?
http://www.proptach.com/
 
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