Tech; Jet Stage II Module



Are you really sure you want a Jet Stage II for your Ram?




Jet II n my 5.9 Indy
98 season of racing I joined the points. Wanted to be more consistent then so I added  2x4 Belltech & Weld Draglites with Mickey Thompson Sportmans & Street Et slicks. I also wanted Hypertech at the time due to price over MP comp. & heard some bad things about the Jet. My parts supplier couldnt get the Hypertech so he ordered a Jet instead thinking there was no difference.  Wasn't too pleased about the situation but thought I'ld give it a try seeing as how the season was starting (points) & I needed some more speed. Well I was disappointed to say the least.97 ran 15.37. 98 15.22. ET's only dropped .15 on the 1/4. I figured the tires & rims for .2 min due to a 125lb weight loss on rim & rubber + greatly increased traction on the starting line & smaller dia. rubber giving a final of around 3.88(3.55 stock). All these things added up to a loss of hp & torque from what I could tell. Noticed it would really bog off the line and had difficulties doing the burnout. I ended up changing to 3.92 gears (4.18 final) later in the season cause of the difficulty spinning the tires. Dropped .1 off(expected that) for seasons new best of 15.13. 

99 I dropped the Jet stage II for a MP PCM. Also changed to 8.0 wires and added a Hi Flow cat. If the Jet worked I should have been up about 4-5hp(.05) for the PCM and about 20hp(.3) for the cat for a .35 total.

Instead my ets dropped by .66! Ran a new best of 14.496. I figured the cat for about .3 reduction. The MP PCM claimed 20hp. That should have given about .3 as well. Figure the other .06 for the loss caused by the Jet Stage II. I couldn't believe the difference. Almost pegged the rev limiter the first burnout on the slicks. 

Biggest reason for pulling it was the
DANGEROUS CONDITION THE JET CHIP CAUSES.

I pulled the module after an increase in # of times that while driving the module would cut out completely killing the engine, power steering & power brakes. Would usually happen on the highway at 70 mph. Started doing it on the street as well & was always on a bumpy section, pothole or expansion joint.
Scared the hell out of me a couple of times once with no where to bail on the highway in heavy traffic in the fast lane. Not a fun situation.

The Jet modules piggy back the computer with the harness hanging off the module. Makes for a kind of long heavy electrical connection that combined with a firmer suspension & shitty roads caused this situation.
If you have one you may want to tie it down with multiple tie straps.
If the tabs get stretched you could have this problem.

RM Indy@WOT


Others Have Similar Gains

R/T Daks dyno camparison
While in the Dak mailing list I found this Dyno printout someone had
submitted on their findings with the Jet module compared to stock computer on a 5.9 Dakota.
PS. It's not a 5.7 but probably the only input # in that range for the dyno's software.




Jet II vs Stock Computer
Atmospheric conditions identical except the Jet had a slight temp. advantage over the stock computer. on its dyno run. Test only show from 3000rpm +. HP is lower on avg. with the torque really dropping off in the upper rpms. I know when I had mine in, it really bogged off the line.  Its probably even more of a spread off idle on the hp/toqure not in Jets favor.

DON'T BUY JET!!!!


Only get the Mopar PCM. You won't be disappointed like you will with Jet. 

Heres the part#s to see if one is available for your year and model. Some have been happy running 4x2 pcms on 4x4 models


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