Dumb question, but valid...

[MrC1]

2007 Charger SRT-8
Cat-back exhaust, CAI, TB spacer, Jet Stage II Chip, 190* stat (the 180* threw codes)

I always run 93 octane.

The previous owner installed all the mods listed above. I compared with and without the Jet chip and the only thing I noticed (seat of the pants and 0-60 runs on the EVIC) was slightly impoved shifting at all throttle postiions.

I just bought the Predator and installed the 91 octane CAI tune. I left the Jet chip in place for now. The seat of the pants is noticable and the WOT shifts are even better now. I couldn't best my previous record 0-60, but I attribute that to traction issues.

I tried the 93 octane CAI tune, but didn't notice any difference in the seat or on the EVIC, so I swapped backto the 91 tune for engine safety.

At this point I'm planning to leave the Jet chip in there for the part throttle shifting improvement, but I wanted to ask if that chip affects fuel mapping or spark timing......so I should remove it. If not, it seems like leaving it would be fine.

What're your thoughts?

Could this chip be why I didn't see any improvement going from 91 octane to 93 octane tunes? Maybe the timing was simply too advanced when running the 93 tune? Could it be that the 91 tune plus the Jet chip is resulting in something close to the 93 tune without the chip?

Just a few thoughts I'd liek to get straightened out.

Thanks!!

[fordomatic69]

Wow, leaving the Jet chip in and adjusting with the Predator? You are a brave soul indeed. You really need to log for ST and LT knock. I bet the reason you didn't see much with the 93 tune is because the knock sensors detected a bunch of knock because your timing was so far advanced and the ECM pulled timing to save your engine from the Big *BOOM*. Set up the predator to Log ST knock, LT knock, Timing advance, IAT, etc. and review them carefully. Just my .02

[Quick]

General consensus on the Jet chip is that it's completely worthless.

[Mike_Levy]

Get that Jet piece of crap out of there. Its messing with the readings. You can't use two things that do the same thing in different ways. They just fuck with each other and you're gonna blow something up. Personally, I wouldn't even start the car again until that POS was out.

[jtfinklea]

Mike how are you making out with the 300C SRT8 that thought it was an amphibious vehicle.

[Mike_Levy]

Not sure yet, Haven't heard much. Gonna bother the dealer today. Went out looking for replacements yesterday. Probably gonna get a Grand Cherokee SRT8, because I love the 6.1, but obviously need a truck.

[MrC1]

Does anyone know if the Jet chip actually adjusts the timing?

[fordomatic69]

I am sure that is the idea behind all the performance type electronic gadgets. Timing Advance to just before detonation for best performance. It's much more complicated than that (Fuel, spark, shifts, etc.).

[MrC1]

The reason I ask is becasue Jet doesn't touch the fuel mapping (on this car at least). Hard to say what all it actually does affect, especially if the consensus is that it does nothing for performance.

[fordomatic69]

Well, judging from the "Beta" tune that I and some others are running, I can assure you that fuel mapping, air clips, timing, shifts, etc. are all adjusted and adjustable with the predator. The CMR tuners have way more flexibility than those of us without the CMR software.

[MrC1]

I just spoke to Jet. Their Stage II chip (the one I have) adds 5-8* of timing, depending on RPM. Wow. Wonder how much the Predator 91 octane and 93 octane tunes add???

I've still got BOTH. haha

I'm running with the 91 tune and it seems to run great. I bet I'm exercising the knock sensor and auto timing retard of the computer pretty well!

I plan to take the chip out tonight. I'm just a little crazy, not a masochist.

[RFischer]

I have proven Dyno results that the Jet Stage 2 does nothing. I gained 10HP across the whole band with the Predator.

[MrC1]

Hey guys, I tried data logging a WOT run with both the 91 octane tune and the Jet Stage II chip. The car was pulling as much as 4.5 degrees of timing out to prevent detonation.

Here's the kicker.......

I disconnected the battery and removed the Jet chip, then retested. Guess what? The car now pulled 7.5 degrees of timing out. HUH???

That's very weird.

I'm running 93 octane with the 91 CAI tune. I also have the stat and fans set up to keep the car under 200*. I wouldn't think it would need to retard the timing at all!

Guess I shouldn't try the 93 tune, huh?

[Mike_Levy]

SRT8s are known to detonate. You gotta customize the program to suit your car. If you don't know how, then find a CMR dealer and have it done. Trying to do what you don't know about can cause a huge hole in your bank account.

[fordomatic69]

Wow, sounds like your car ate a breakfast burrito.... BAD GAS!