Installed Magnuson SC on '21 JL 6-speed - Positive Experience

[kis_face]

The stock 3.42 gears/6 speed are prob awesome with that s/c...

I saw you got to 60 in 2nd gear

For how I use it 3.45 gears work great with the supercharger and 33" tires. I considered regearing prior to the s/c and now glad I didn't.

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[Rodeoflyer]

Yeah you wouldn’t want (or need) to regear with that massive power upgrade. It runs like a spotted ape now.

 

[kis_face]

**MPG Update**

I've driven 1,029 miles since installing the supercharger and analyzed my fuel milage while driving different styles. I maintained specific driving styles for many miles in various conditions to obtain an accurate conclusion.

If I drive conservatively I'm actually able to gain 1 to 2 MPG versus when I drove just as conservatively prior to having the supercharger. No matter how gentle I drove without the S/C I could not achieve the MPG I'm capable of with the S/C.

If I drive using some boost here and there like when pulling away from traffic lights or merging onto the highway, I average the same exact MPG I was getting prior to installing the S/C.

If I drive like a mad man, which seems to be the most common style for me haha (enjoying that supercharger) I lose 1.5 to 2 MPG.

I have been surprised and rather pleased by these numbers. After installing the supercharger I was prepared to get much worse mileage across the board, but that has not been the case. Another positive for this install.

I'm happy.

 

[Anu2g]

Thanks for the great write-up and video. I'm strongly considering this as my next mod for my 6-speed '21 JLR. Most of what I saw online prior to this post was not specifically for manuals, so your write-up is a serious confidence boost. Pun intended.

 

[kis_face]

Thanks for the great write-up and video. I'm strongly considering this as my next mod for my 6-speed '21 JLR. Most of what I saw online prior to this post was not specifically for manuals, so your write-up is a serious confidence boost. Pun intended.

Since you have a 2021 model year you need to confirm your PCM is a GPEC2A and not the GPEC5. Jeep was forced to transition to a GPEC5 PCM mid year 2021 due to the chip shortage. The GPEC5 cannot be unlocked by HP tuners at this time. Therefore you cannot load the tune necessary for a supercharger. It would be a bummer if you discovered that after purchasing a supercharger.

 

[Anu2g]

Since you have a 2021 model year you need to confirm your PCM is a GPEC2A and not the GPEC5. Jeep was forced to transition to a GPEC5 PCM mid year 2021 due to the chip shortage. The GPEC5 cannot be unlocked by HP tuners at this time. Therefore you cannot load the tune necessary for a supercharger. It would be a bummer if you discovered that after purchasing a supercharger.

Thanks for the tip; I just saw that 10 min ago on Magnuson's website. My rig was built in December '20, so I think I should be OK, but would confirm beyond any doubt prior to placing an order.

How many hours/days did the install take you? I'd probably need to allocate around twice whatever it took you, if not more, judging by the proficiency you showed in the video.

 

[Rodeoflyer]

That's very interesting.. I know I have the early type (connectors on face) due to checking it out when I was looking at Livernois perf tunes.

 

[kis_face]

Thanks for the tip; I just saw that 10 min ago on Magnuson's website. My rig was built in December '20, so I think I should be OK, but would confirm beyond any doubt prior to placing an order.

How many hours/days did the install take you? I'd probably need to allocate around twice whatever it took you, if not more, judging by the proficiency you showed in the video.

I installed mine over the course of about 5 days only working on it 1-3 hours at a time. I'd say the entire install took me a total of about 15 hours. The kit can definitely be installed a lot quicker but I took my time, rushed nothing, and enjoyed the process.

 

[Anu2g]

I installed mine over the course of about 5 days only working on it 1-3 hours at a time. I'd say the entire install took me a total of about 15 hours. The kit can definitely be installed a lot quicker but I took my time, rushed nothing, and enjoyed the process.

Cool; that's the way to work! I like working in half days, that way frustration is kept at a minimum. Were there any sticking points during the install? Asides from the tune, anything that didn't just fit into place or required some extra debugging?

 

[kis_face]

Cool; that's the way to work! I like working in half days, that way frustration is kept at a minimum. Were there any sticking points during the install? Asides from the tune, anything that didn't just fit into place or required some extra debugging?

No issues whatsoever. This kit actually surprised me with how thought-out everything was. Nothing fought me and everything went together flawlessly. Even the tune wasn't really an issue as it only takes a few minutes to load a new one. But if I had to say anything about anything here are a few things that required self thinking -

• The routing of the hoses for the intercooler wasn't very clear in the manual. Pictures and instructions contradicted each other. With a few minutes of testing different routes it was easy to figure out on my own. But relying on the manual to tell me exactly where to route things wasn't helpful. Once I figured out how they intended the hoses to be ran they fit perfectly. Every hose is custom bent and molded to fit perfectly where it should.

• One of the early steps instructs you to bend the aluminum EGR cooler tube towards the battery about 20 degrees. I had a hard time deciphering how far to go as 20 degrees was hard to determine in that space. So I errored on the lesser side because I didn't want to bend it too far. It wasn't until I went to install the upper intake manifold that I realized I didn't bend it quite far enough (I included that in my video). So I had to work on that step a bit more before I was able to get the upper intake manifold to fit with proper clearance.

• The wire harness separation that they instruct in the manual regarding the horns and outside thermostat made no sense. You have to separate some wires from a wrapped harness to give enough length to relocate the horns and reinstall the outside temperature sensor. I scrapped what they instructed in the manual and did my own thing which worked perfectly. I ended up mounting the outside temp sensor on the driver side front closeout panel with a clear shot of fresh air through the grill. It's accuracy has been maintained. Where the manual instructs to install the sensor on the passenger side was impossible given the length of the factory wire harness.

• Lastly the coolant cap on the intercooler reservoir needs to be a lower profile design. Either that or the reservoir needs a shorter neck. This is the only design flaw I've discovered. The current design is a bit too tall so the cap rubs ever so slightly on my hood liner. Eventually it will wear a hole in it and I will just remove the piece. But for someone like me that likes everything to be perfect it bothers me a little. Here is a picture of what I'm talking about -

 

[FLjeeper]

How long did it take start to finish?

 

[kis_face]

How long did it take start to finish?

Taking my time and not rushing anything, about 15 hours

 

[Krondor]

Since you have a 2021 model year you need to confirm your PCM is a GPEC2A and not the GPEC5. Jeep was forced to transition to a GPEC5 PCM mid year 2021 due to the chip shortage. The GPEC5 cannot be unlocked by HP tuners at this time. Therefore you cannot load the tune necessary for a supercharger. It would be a bummer if you discovered that after purchasing a supercharger.

Damnit. I have the supported PCM.

 

[FLjeeper]

Taking my time and not rushing anything, about 15 hours

That’s not bad at all. Great read! I have a 6spd and am seriously considering this upgrade now.

 

[LT1Chevy210]

Damnit. I have the supported PCM.

I have a used supercharger sitting in my basement if you're interested...

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