Are Supercharger Issues Entirely Related to Tuning or also Hardware?

[kyoung05]

Interesting to hear all of the varied feedback.

It's good to hear that there are folks who have been running a supercharger kit for some time without issues. Even better to hear that custom tunes are available - and it's just a matter of finding the right tuner that is able to tune for this application.

I do agree that the difference between tuning an NA engine that is running aftermarket FI is very different than tuning an engine that came turbocharged from the factory, and that is probably contributing to some of the issues. That said, there are lots of aftermarket FI setups being run on NA motors (i.e. the 5.0l Mustangs, LS/LT engines, and even some of the older Honda motors before they started coming turbocharged). In all of these instances, there seems to have been robust aftermarket support and the availability of custom tuning wasn't an issue. Of course, those are all performance platforms whereas the Jeep is not, so maybe it's just a difference in demand driving the lack of supply.

I am bummed to hear that even with the supercharger the 3.6 is so far away from the 392 in terms of performance. I was originally going to plan for a 5.7 or 392 swap when I thought supercharging wasn't an option. However, after discovering that I have one of the older ECU's, I was hoping to get somewhat comparable performance for a fraction of the cost. While a Hemi swap would be awesome, prices start at $30k for the 5.7 and $40k for the 392, whereas a supercharger kit is probably $10k all-in (with installation and tuning). I wouldn't have expected 100% of 392-level performance for 25% of the cost, but I was hoping it would be closer to 70-80%?

My shop recommended regearing as a first step to increase the performance, and then the Edelbrock supercharger if I still feel the need for more power. I think this seems like a reasonable approach, since the regear is the cheapest option, and from what I've read, can improve 0-60 times up to 1/2 second. From what I've seen, that's about what you get from a supercharger w/o regear. Some of the videos I've seen show 0-60 in the 6.5s range with the supercharger, which is about a full second slower than a 392 Wrangler it seems.

Sponsored

 

[redriderjf87]

Like mentioned, I would regear first. If you can get enough extra performance without touching the motor, that's ideal.

Forced induction on the 3.6 would scare me personally. I would either pony up for a 5.7 or buy a square body Chevy and would trust either of those options a lot more

 

[staying_tuned]

Not sure if you have an end game in mind but if you itemize out the journey while factoring in loss at resale time, you may end up spending closely the same if you consider a high mile sport (mid 20s) or high mile rubi (low 30s) to start as a doner for a 5.7 or swap. Run the snot out of the doner for a bit while saving for the swap. I had a great condition, rust-free 110k mile sport bookmarked at $24k with the hard top. Spoke to 2 builders and in both scenarios, for a 5.7, my total cost would have been under $60k with enough leftover to hit it with a mild suspension, wheel and tire upgrade as well.

Not sure what it is about a hemi swapped Wrangler or Glady but it’s one of those rare scenarios where once complete, should you decide to part with it, they typically can be sold for more than you put into them.

 

[BearDog]

For months I considered a supercharger for mine. That cost vs a Hemi is much cheaper initially. Almost pulled the trigger a couple of times. Then I got to thinking... If mine was one of them that started having issues (highly likely), it would end up costing as much or more than a Hemi because it would mean time for a new motor. I stopped considering it.

Once paid off, mine will go to Exodus and get the 6.4 Hemi swap with the HD trans. Yes, another "truck payment", but the right choice for me considering I plan on keeping this thing 'til I can't physically drive anymore.

Does it "need" it? No, the 3.6 does everything I ask of it just fine.

Do I "want" it? F*ck yea!!

And as said above...once I'm dead and done, my wife and/or kids can sell it for a chit ton and split the money

 

[kyoung05]

Not sure if you have an end game in mind but if you itemize out the journey while factoring in loss at resale time, you may end up spending closely the same if you consider a high mile sport (mid 20s) or high mile rubi (low 30s) to start as a doner for a 5.7 or swap.

I think this is a really good way of approaching this. I wasn't sure what to expect when I bought my Gladiator - it was my first truck, and my first Jeep. I never intended to be hardcore into crawling, and that remains true today. However, I did want it to be a pretty capable off-roader (in terms of mud/sand/rough terrain/etc.) and I think I am still leaning towards that route.

If I had to summarize my end goal, it would be to make my Gladiator into a "Fun Go Fast, Do Anything, Anywhere" truck. This isn't my daily driver, or even my weekend car. It's a third vehicle that I bought as sort of a fun project that has now turned into what I end up driving 99% of the time.

To put it into perspective, before the Gladiator, I was considering a TRX or an F-150 5.0l w/ Whipple Supercharger (would've also considered the Raptor, but really wanted a V8). I think either of those probably would've been better for most of what I am looking for. However, neither of them are convertibles, and more importantly, neither can be had with a manual transmission. I didn't think the convertible aspect would matter that much, but I knew for certain the manual transmission was a must have.

Basically, I'm looking for a "TRX-lite" w/ manual transmission and convertible top.

As it sits, I think my Sport w/ the Clayton 1.5" level kit, Billie Bars, Awning, Roof Top Tent, and 33" tires satisfies most of my wants. I am going to be installing Falcon SP2 3.3 shocks soon, and hopefully that will make it a bit more 'desert-runner' like in terms of ride over rough terrain. The only thing missing is really the "fast" part of the equation.

I am really torn between a Hemi swap of some kind, or just going with a supercharger and regear. I'm not really looking at this as an investment that I need to retain resale value. IMO, once you start modifying a car, I am assuming that all of those costs become sunk and I wouldn't expect to recoup any of them in the long run. Instead, I'm more focused on the value proposition of the supercharger + regear (~$12-15k) vs. Hemi swap ($30-40k). If I can get most of the performance that I would from a 5.7 or even 392 swap for a fraction of the cost, all things being equal, that's probably what I'd lean towards. However, if it turns out that even with the regear and supercharger the performance is inadequate, or a lot more unreliable, I will probably regret having spent that only to end up with a Hemi swap in the end.

 

[MarylandMojave]

Find a SC one local to you if you can and drive it, then decide. I’d say 50% of the people that do a SC looking for 392 power for cheap end up doing a 392 swap after all.

 

[cmb396]

Find a SC one local to you if you can and drive it, then decide. I’d say 50% of the people that do a SC looking for 392 power for cheap end up doing a 392 swap after all.

Owning a maggi charged JTR and a 392XR, I just want to comment on anyone reading this in the future, there is ZERO comparison to a sc'd 3.6 and 392, lol.
That said, my JTR is on 39's and has 513 gears, so in no way feels "fast". The power and torque is there for towing, and loaded down with camping gear, which was my intent to not be bogged down here in the hills of WV on trips.
The 392 is on 37's and has the 456 gears and just flat out rips.
After purchasing a 392 last summer, I am blown away by how well they run, and truly wished Jeep would have made a 392 JT!

 

[kyoung05]

Owning a maggi charged JTR and a 392XR, I just want to comment on anyone reading this in the future, there is ZERO comparison to a sc'd 3.6 and 392, lol.
That said, my JTR is on 39's and has 513 gears, so in no way feels "fast". The power and torque is there for towing, and loaded down with camping gear, which was my intent to not be bogged down here in the hills of WV on trips.
The 392 is on 37's and has the 456 gears and just flat out rips.
After purchasing a 392 last summer, I am blown away by how well they run, and truly wished Jeep would have made a 392 JT!

Wow, I realized that they wouldn't be equal in terms of performance, but didn't expect them to be so far apart either. Especially since you have the 5.13 gears with the supercharger - that's probably as aggressive a setup for acceleration with the V6 as you're going to get. I am probably not going to run any larger than 33 or 35's maximum, but even then, doesn't sound like it'll be close. While the 392 swap would be about 4x more expensive, it's sounding more and more like it'd be worth it - especially if I can keep the 6spd manual.

 

[MarylandMojave]

I’ve never seen a 392 with the manual transmission, not sure it would hold up.

 

[cmb396]

Wow, I realized that they wouldn't be equal in terms of performance, but didn't expect them to be so far apart either. Especially since you have the 5.13 gears with the supercharger - that's probably as aggressive a setup for acceleration with the V6 as you're going to get. I am probably not going to run any larger than 33 or 35's maximum, but even then, doesn't sound like it'll be close. While the 392 swap would be about 4x more expensive, it's sounding more and more like it'd be worth it - especially if I can keep the 6spd manual.

My truck is on the plump side as well. I believe it weighs around 7200lbs with me and a full tank of gas. Steel bumpers, winch, rock slide engineering retractable rails, bed rack and basket, etc.
IDK what the 392 weighs, but much lighter. Don't get me wrong, my JT runs great, for what it is, but the seat dyno goes to the 392 hands down.

As for the 6 sp, like mentioned above, i have never seen that done. Does the diesel offer a 6sp? I'm not even sure if mopar offers a manual in their HD trucks anymore?

 

[kyoung05]

I actually reached out to MMX about whether their 392 swap could be done with a manual, and it sounds like it can, but they will swap in a GETRAG238 transmission because it is rated for higher power applications. The more I am looking into this, it sounds like the Hemi swap might be the better option to go with rather than supercharging an engine that doesn't seem that receptive to it, and then hoping for the best (all the while missing out on the additional power and sound that the 392 offers). I just need to come to terms that the swap will basically double the cost of my truck....

 

[cmb396]

I actually reached out to MMX about whether their 392 swap could be done with a manual, and it sounds like it can, but they will swap in a GETRAG238 transmission because it is rated for higher power applications. The more I am looking into this, it sounds like the Hemi swap might be the better option to go with rather than supercharging an engine that doesn't seem that receptive to it, and then hoping for the best (all the while missing out on the additional power and sound that the 392 offers). I just need to come to terms that the swap will basically double the cost of my truck....

If the cost is not an issue. I would def do the 392 swap.
I still may one day tbh. My dd is a 23 raptor, so plenty of umph with that truck. The jt is mainly for camping and jeeping.

 

[Stan H]

How about hunting around ad finding a 392 . Then just installing it yourself. What kind of issues are there to that. ECM's adapter plates, wiring harnesses. Is it possible to do it yourself?

 

[Tbanks]

My current setup:
3.6 motor (Sleeved block, MMX forged pistons/rods/balanced crankshaft, ARP headbolts, v8 throttlebody) Tuned by Dave

Magnuson Supercharger-

The Jeep is finally finished yesterday, so I'm breaking in the motor first then going to try and push 500 to 550whp (620 crank) using a dyno. Which would give me more power then 392. I'll let you guys know how it goes.

I wish I would of just went 392 lol

 

[kyoung05]

My current setup:
3.6 motor (Sleeved block, MMX forged pistons/rods/balanced crankshaft, ARP headbolts, v8 throttlebody) Tuned by Dave

Magnuson Supercharger-

The Jeep is finally finished yesterday, so I'm breaking in the motor first then going to try and push 500 to 550whp (620 crank) using a dyno. Which would give me more power then 392. I'll let you guys know how it goes.

I wish I would of just went 392 lol

Awesome that you've built the 3.6 to handle extra power and provide some additional safeguard!

Out of curiosity, did you run the supercharger on the stock motor first and then decide to upgrade because of reliability or power concerns? Or, did you always plan to make ~500whp from the get go?

Reason I ask is MMX mentioned they could do the Procharger kit with their forged pistons and rods to beef up the bottom end for a little less than 1/2 the cost of the 392 swap. However, I don't know that this would entirely address the 3.6's shortcomings, and I'd still be stuck with the stock manual transmission which is already subject to a recall due to the clutch and its inability to cope with higher power loads. I guess factoring in a new clutch, I'd still be at about 50% the cost of a 392 swap, but I'm wondering if I'd be twice as happy with a 392 regardless....

Sponsored