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 #317111  by Gorm
 September 8th, 2013, 2:09 pm
Overall impression...not impressed.

I swapped my 2003 special computer for one from a 2002. I was not impressed. While the shifting did become firmer, this was the only thing that seemed different to me from my 2003.

Now, I cannot speak to the upgrade if you were going from a normal 300m or Intrepid controller to the 2002 Special computer, but from a 2003 special to a 2002 special, not worth it at all.

I was expecting to be the same type of computer that my Intrepid had with the 300m PHP computer. I really loved the PHP in the Intrepid, I was able to chirp the tires each time I hit the gas, I can't recreate that with the 03 or the 02 Special Computer. Of course the Intrepid didn't have ABS or Trac, so that could have played a big part in that as well.

Some things to note about the swap:

You must select your engine controller very carefully. You need to quiz the seller on what type of car it came from and what the options were. Buying a computer without this information could be a disaster for you.

1. If your special has side airbags, the 02 Special PCM must also have had side airbags, otherwise you will get an Airbag light. This is also true of the opposite, if your 02 Special PCM is expecting side airbags and doesn't see any, it will likely throw an Airbag light.

2. If your special has 18" rims, the 02 Special PCM must also have 18" rims. This is so your speedometer is correct and that you have no limiter. The 17" rim 02 Special PCM has a speed limiter on it.

3. Sentry Key -This must be provided along with the sentry key module from the car. If you are missing one of the three items, the other items are useless.

4. Unless you have the dealer configure the PCM for you car (expensive) or have the lock cylinders from the doner car, you will lose your sentry key protection.
User avatar
 #317114  by 300maximilien
 September 8th, 2013, 2:24 pm
Gorm wrote: Of course the Intrepid didn't have ABS or Trac, so that could have played a big part in that as well.
Did you leave this on when trying to "chirp" the tires?
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 #317126  by Gorm
 September 8th, 2013, 5:07 pm
I tried it both with and without trac. I did get a bit more with it off, but nothing like I was used to with the intrepid. My guess is that there is still some sort of torque management going on even without it on.
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 #317132  by paintballdude05
 September 8th, 2013, 7:05 pm
Gorm wrote:2. If your special has 18" rims, the 02 Special PCM must also have 18" rims. This is so your speedometer is correct and that you have no limiter. The 17" rim 02 Special PCM has a speed limiter on it.
I have never seen an '02 Special w/ 17's from the factory. If the PCM is set for 17" wheels and tires, then it was done by the dealer. At that, I don't even think it was an option in the Special PCM but you never know.

I did the same swap on my '03, no huge difference. I noticed slightly higher shift points and shift firmness.
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 #317136  by mabraham
 September 8th, 2013, 7:13 pm
Gorm wrote:I tried it both with and without trac. I did get a bit more with it off, but nothing like I was used to with the intrepid. My guess is that there is still some sort of torque management going on even without it on.
I will add this information to corroborate your information with my own personal experience. In my m, once the car is running I can slowly turn my ignition switch twards the off position and in the process kill a lot of things, but the engine still runs. Rest assured traction, abs, and airbag lights all come on, and I can speak for certain that traction control and abs do not function while driving. In this condition the wheels will spin, quite differently than when t/c is off in normal operation. There is a noticible difference in handling as I feel torque management is effected.
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 #317197  by LUNAT1C
 September 9th, 2013, 5:38 pm
FYI, no 02 Specials came with 17" wheels. All Specials technically have a limiter, somewhere north of 140 where no one really goes anyway. To my knowledge the only change from 02 to 03 was the shift pattern you described. Tapping the T/C button will not completely disable T/C in just about any car. Not even SRT vehicles (can be fully defeated only via certain hoops in current SRT vehicles).

I haven't driven any LH vehicle other than 02 Specials since my ES in 2005, so I've no idea what anyone expects from this upgrade.

Sent from my DROID RAZR HD using Tapatalk 4
User avatar
 #317215  by 02SilverSpecial
 September 9th, 2013, 8:51 pm
This is what the 02 Special Computer allowed my 02 Concorde Limited to do:
I added the PCM and gearing to it
User avatar
 #317218  by Gorm
 September 9th, 2013, 8:59 pm
Anyone have a 2002 300m brochure to see if they mention the 17" inch chrome wheels? At least two of the 2002's I looked at getting before I bought my 2003 had the 17 thin spoke chrome rims on them. It was a more common option on 03 and 04 models than 02. I'm sure dealers didn't want Specials on their lot with anything less. I'm sure this why some had them chromed as well.
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 #317221  by Gorm
 September 9th, 2013, 9:01 pm
Even if the wheel thing is not an issue...the airbag issue is still a problem. I had this problem with my first 02 controller. Second one did not.
User avatar
 #317222  by 300maximilien
 September 9th, 2013, 9:10 pm
18" Wheels were standard equipment on '02s (143mph limiter) and an option on '03-04s. The chrome 17" twin-sixes were standard on '03-04s (132mph limiter).

One would think that the 17" wheels would not have been an option in '02 as they would have been a downgrade and required a lower speed setting.

And this info from TFC would tend to support that...



2002 LH
3.5L HO
NLEV 108 MPH........................................5102176AC
NLEV 132 MPH........................................5102177AC
R/T NLEV 132 MPH...................................5102178AC
GCC 132 MPH..........................................5103278AB
EUROIII 149 MPH......................................5103236AB
R/T Mexic0 132 MPH..................................5103239AB
HO Mexico 132 MPH..................................5103234AB
NLEV 108 MPH w/o EGR..............................5102181AC
NLEV 132 MPH W/O EGR.............................5102182AC
JAPAN, 149 MPH.......................................5103238AB
3.5L Low Output, all are 108 MPH limit
300M Special, 143 MPH..................................5102189AB & 4896554AE

2003 LH
All 3.5L HO engines....108 or 132 MPH for North America, 149 MPH European, 108 MPH Mexican, Gulf coast & Japan.
All Low Out put 108 MPH
300M Special, 132 MPH.....................................4896510AD
300M Special, 143 MPH.....................................4896509AD

2004 LH
3.5L HO engine speeds the same as 2003.
3.5L Low output speeds the same as 2003
300M Special, 132 MPH...................................4896510AD
300M Special, 143 MPH...................................4896509AD
300M Special, 143 MPH, gulf Coast.....................4896515AB
User avatar
 #317235  by LUNAT1C
 September 9th, 2013, 10:20 pm
Remember in 2002 the original owners of these cars complained at how aggressive they were and they were detuned for 03 and 04. I wouldn't be surprised if some didn't like the lower profile tires and ordered with 17s.

Sent from my DROID RAZR HD using Tapatalk 4
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 #317240  by Gorm
 September 9th, 2013, 10:52 pm
300M Special, 143 MPH..................................5102189AB & 4896554AE

So why the two different versions? What makes one different from the other?

I think the side airbags might come into play here. It could also be simply a matter of BCM mismatch on the side airbags. I have never heard of someone having an airbag light problem, I was quite shocked when mine gave me one. I did confirm that car that my computer came out of did NOT have side airbags.
User avatar
 #317249  by paintballdude05
 September 10th, 2013, 7:56 am
Gorm wrote:300M Special, 143 MPH..................................5102189AB & 4896554AE

So why the two different versions? What makes one different from the other?

I think the side airbags might come into play here. It could also be simply a matter of BCM mismatch on the side airbags. I have never heard of someone having an airbag light problem, I was quite shocked when mine gave me one. I did confirm that car that my computer came out of did NOT have side airbags.
EGR and non-EGR cars would have different PCM programming. Early 02's still came with EGR even though it is somewhat rare to see.
 #317251  by Shadowvox6
 September 10th, 2013, 9:19 am
When I went from my stock 04 Special PCM to the 02 Special PCM, to me it was night and day.
The 02 seemed to be more aggressive with timing / spark, fuel, and obviously shift points.
I never thought it was a bad mod....
I still feel it was one of the better mods I did.
The best of course being the torque converter.