Sprintex 3.6 pentastar install

[Icheer4beer]

Under full throttle it has no problem shifting. It shifts around 6.2 all the way up to 80. And honestly it feels as fast as my old 77 Porsche 930.

[bo9roadking]

Sounds like Sprintex has figured out the auto transmission. Magnuson is still trying to get the auto shifting resolved. With the latest tune that I have, the transmission will shift on its own at about 3k rpm from 1st to 2nd, 2nd to 3rd is about 4.5k rpm, and the other gears are at about 3k rpm. I can manually upshift at a lower rpm or let off the gas slightly to shift sooner if I want. Wide open throttle shifts just prior to redline on its own unless I manually upshift.

I can live with the way it shifts around town, but it definitely doesn't shift like it did when it was stock. My main problem with this tune is that my overdrive is almost useless. On level ground or downhill, overdrive works. Any incline that requires throttle input to maintain speed will kick the transmission down to 4th gear and it will stay there for a long time unless I manually upshift it. There are some sections of the interstate that I have to deal with higher rpms in 4th gear because manually upshifting only lasts for a few seconds and then it downshifts back to 4th on its own. If I continue to manually force the transmission into overdrive, it will shift up and then back down as soon as I manually upshift like a yo-yo. I live in Texas and the interstate is not in the mountains or any hilly terrain. I'm talking elevation changes of maybe 20-30 feet. If I hold the gas pedal and don't try to maintain highway speed, the transmission will stay in overdrive, but I'll lose about 5mph in the process. If I press the gas pedal to maintain speed, it drops out of overdrive.

For a power adder, I would think the extra hp/tq of the SC would cause the transmission to downshift out of overdrive less often instead of more often than it did when it was stock because the extra power would keep things moving without requiring a transmission shift. Magnuson has been working on a new tune for over two weeks, but SEMA has slowed down progress. Hopefully I'll get better results with the next tune.

[Gunner]

Sounds to me like there is a winner here for automatics.

[Gunner]

I just talked to the Sprintex Guys. I think that I am going to be buying one of these for my Jeep. This is exactly what I was hoping for. A twin screw.

[Yoinkers]

I just talked to the Sprintex Guys. I think that I am going to be buying one of these for my Jeep. This is exactly what I was hoping for. A twin screw.

WHOA! You are just the guy to do it. Gunner is the jeep that was gonna do the top speed run right? (crazy, but i like your style)

[FieryRobot]

New member here. Very happy to hear this about the Sprintex. I have been researching superchargers for what seems like forever at this point. That might be enough to push me over the edge. I like the looks of that RIPP intercooler, but the install seems more invasive.

My search has gone something like this: "I think I want the RIPP, looks hot!" "Hmm. What about this Sprintex? Install seems neater" "Oh, hey, there's a Magnuson, similar to Sprintex, but seems to have issues still", "What? A turbo!? Power! But lag (I don't care what anyone says). And still more invasive and I don't know if I can deal with exhaust leaks." "I really like that RIPP. Maybe that's where I'll end up" "Oh, the Sprintex has solved the shifting issues?!"

Needless to say, it's been tough to keep track of all of the pros/cons of all of these systems. Thankfully I've found the threads on wrangler forum and here to help me sort this out.

[Pznivy]

Sounds like Sprintex has figured out the auto transmission.

^^ This i do not buy. They always talk like this when no one has the unit. they love to say "We've solved all the problems that the other SC companies have struggled with for years". No one should believe that. A power mod has too many variables for it to be perfect, in your area, on your gas, on your jeep.

They need a bunch of jeeps everywhere installed and logging to get enough data to make the tune perfect. It takes a long time. JL had the first pentastar RIPP, they will agree with this. JG had the first turbo, and Prodigy said their tune was perfect. It wasnt.

Only when a few people NOT attached to sprintex confirm its perfect would I believe it.
.

[Gunner]

It really looks like everyone has some sort of problem. I drive most of the time with a light throttle and below 3000 rpm. Mine is an auto. I think if I want to be safe the Ripp is the way to go. But if I want bottom end then I want a screw. I wish the Maggie was more sorted out. I love the scream they make when you kick them in the pants. I'm still deciding but yeah I am gonna do a speed run. I just don't know how high I will go.

[Icheer4beer]

I am not associated with sprintex at all. I am a pilot for United Airlines. Sprintex is not perfect. As for the transmission problems. I really don't have any. If I go max blast it does shift by itself. Sometimes if I am just driving I do force the shift. I am trying to converse gas and I want the shift points where I want them. It's a personality defect.

Gas mileage has settled down to 14-15 mpg combined. If I gun it a lot it goes down to 12.

The only negative is that it does not like the cold. If temp is below freezing and I don't let it warm up for a couple I might have a misfire. If I let it warm up, there is no problem.

Why did I go with sprintex? Saved over a grand on the other systems and low end torque. It also looks good.

[FieryRobot]

I think if I want to be safe the Ripp is the way to go.

Has RIPP also figured out the auto shifting? The instructions I got from them a while back state you need to lift to shift during heavy acceleration.

• Automatic transmission: Auto transmissions may not up shift at full throttle when driving in “D” (drive) mode, THIS IS a Direct product of OEM programming and not the provided tuning. In order to shift at full throttle, end users may either “lift to shift” by raising the accelerator slightly (partially). RIPP makes no claims as to the reliability of the transmission with the supercharger installed.

That was from months ago, so it's possible this has changed. The last line, while I understand is a CYA statement, also worries me a bit.