Re-gear or Supercharge?

thedern

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I recently got a quote from a local jeep specialty shop to re-gear from 3.73 to 4.56 for ~$2,300. I am pretty comfortable with most bolt-on type work but a re-gear is out of my league. However, for that money I could do a Boosted Tech supercharger myself for only a few hundred dollars more.

I wanted to get an opinion from those who have re-geared, supercharged, and those who did both on which had the greatest effect on performance for highway use. I suppose I am looking for "bang for your buck" opinions from more experienced members. If I am gonna sell a kidney to continue this hobby, I want my kidney to bring back the best return on investment. :)

Thanks.
 
That price for a regear seems very high. Shop around before you go with any specific shop. I can't remember how much my regear was, but it was nowhere near that amount and I also went from 3.73 to 4.56 (not that it would matter that much). What size tires are you running and what transmission do you have? If you have oversized tires, I would regear before I would supercharge. You cannot make up for improper gearing with a supercharger. If you regear and still feel like you need more power then go with the supercharger. But, to be honest, I'd swap a small block in before I supercharged a 4.0.
 
That price for a regear seems very high. Shop around before you go with any specific shop. I can't remember how much my regear was, but it was nowhere near that amount and I also went from 3.73 to 4.56 (not that it would matter that much). What size tires are you running and what transmission do you have? If you have oversized tires, I would regear before I would supercharge. You cannot make up for improper gearing with a supercharger. If you regear and still feel like you need more power then go with the supercharger. But, to be honest, I'd swap a small block in before I supercharged a 4.0.


I thought it was high too. I am shopping around currently, but I saw some posts concerning supercharging on here and wanted to ask for feedback. My current setup is not too bad. 6spd manual, 3.73 gears, 33x12.5r15 tires. Its livable.
 
Both. And take it from someone who has done both (me).

Your posts on supercharging started my research :)

I can only afford 1 right now, so my question more clearly stated would be for the money, which is more effective for highway use? I would ideally like to do both in the future.
 
I thought it was high too. I am shopping around currently, but I saw some posts concerning supercharging on here and wanted to ask for feedback. My current setup is not too bad. 6spd manual, 3.73 gears, 33x12.5r15 tires. Its livable.

I would regear to 4.56 first before you supercharge. I have a 5 speed, 4.56's, and 33's. It is fine for day to day driving and off-roading. I would argue that a supercharger with 3.73's would be worse than a stock 4.0 with 4.56's in terms of drivability, especially when starting off at lower RPM.

After the regear, decide if you need more power. Getting more power out of a 4.0 has never really made sense to me personally. It makes more sense to me to swap the motor out if you really feel like you're lacking power. While people do turbocharge and supercharge 4.0's, I'd look at the pros and cons before you go one way or the other.
 
I would regear to 4.56 first before you supercharge. I have a 5 speed, 4.56's, and 33's. It is fine for day to day driving and off-roading. I would argue that a supercharger with 3.73's would be worse than a stock 4.0 with 4.56's in terms of drivability, especially when starting off at lower RPM.

After the regear, decide if you need more power. Getting more power out of a 4.0 has never really made sense to me personally. It makes more sense to me to swap the motor out if you really feel like you're lacking power. While people do turbocharge and supercharge 4.0's, I'd look at the pros and cons before you go one way or the other.
Thanks for your feedback.
 
4.56 would make a noticeable difference, 4.88 even better. SC, blower, nitrous, etc, will not overcome poor gearing. You still need proper gearing to get the engine into its hp/tq range. And off road gearing will help more than any of those.
 
Your posts on supercharging started my research :)

I can only afford 1 right now, so my question more clearly stated would be for the money, which is more effective for highway use? I would ideally like to do both in the future.
Adding a supercharger would be pushing inefficiently against misgeared axles... a bandaid for a problem that would still be there if you only added a supercharger. Regear to the correct ratio first before doing anything else.

And that $2300 quote you received was likely just a "let's throw this out there and see if the customer is stupid enough go accept our first offer" kind of a deal. Shop around and tell the shops it's competitive. In most parts of the country you can get axles for $1500-1700 or less if you shop around and negotiate/push for a significant discount.
 
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This is all great feedback guys... I appreciate it. My expectation for re-gear (based on posts read) was around $1,500. I was a bit surprised by that quote.
 
Your posts on supercharging started my research :)

I can only afford 1 right now, so my question more clearly stated would be for the money, which is more effective for highway use? I would ideally like to do both in the future.

The supercharger will be better for highway use. It makes it feel as if you’ve got two 4.0s under the hood. Pairing it with the proper gearing though is unreal. I’d start with the supercharger though personally.
 
The supercharger will be better for highway use. It makes it feel as if you’ve got two 4.0s under the hood. Pairing it with the proper gearing though is unreal. I’d start with the supercharger though personally.
I come from Subaru's (only the turbo models) and my daily driver is a Ford Expedition with the eco-boost. I find the allure of forced induction like a drug. I do like that boosted tech...
 
The supercharger will be better for highway use. It makes it feel as if you’ve got two 4.0s under the hood. Pairing it with the proper gearing though is unreal. I’d start with the supercharger though personally.

Man, I would love a test drive in one these to see how it is like. I was looking at the Banks kit and drooling the other day...
 
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I come from Subaru's (only the turbo models) and my daily driver is a Ford Expedition with the eco-boost. I find the allure of forced induction like a drug. I do like that boosted tech...

Same! My other car is a '15 VW Golf 1.8T with a turbo\downpipe upgrade running 21-22 PSI, ~300 HP to the wheels. And, it still gets 35+ mpg on road trips! The car is an absolute pleasure to drive and I proudly did all the work myself for very little $. I'm switching over to modding the Jeep now, but I'll probably have to continue to count on my VW for my boost fix, LOL.
 
Same! My other car is a '15 VW Golf 1.8T with a turbo\downpipe upgrade running 21-22 PSI, ~300 HP to the wheels. And, it still gets 35+ mpg on road trips! The car is an absolute pleasure to drive and I proudly did all the work myself for very little $. I'm switching over to modding the Jeep now, but I'll probably have to continue to count on my VW for my boost fix, LOL.
Was looking at an APR modded Golf R last month... but wife wanted a jeep. So we have a jeep (not complaining).
 
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I come from Subaru's (only the turbo models) and my daily driver is a Ford Expedition with the eco-boost. I find the allure of forced induction like a drug. I do like that boosted tech...

It's a nice setup and very easy to install. I could install it again and have it up and running in maybe a few hours tops, if that. A turbo on the other hand is a ton of work and would take way more than just a simple bolt-on installation.

With the supercharger you can expect around 210rwhp, which is a huge increase, considering that from the factory you only have about 150 at the wheels.

That's also running 6 psi. I was safely running 8 psi on mine without any issue at all. I also don't drag race it, so I'm not treating it in an abusing sort of way.
 
It's a nice setup and very easy to install. I could install it again and have it up and running in maybe a few hours tops, if that. A turbo on the other hand is a ton of work and would take way more than just a simple bolt-on installation.

With the supercharger you can expect around 210rwhp, which is a huge increase, considering that from the factory you only have about 150 at the wheels.

That's also running 6 psi. I was safely running 8 psi on mine without any issue at all. I also don't drag race it, so I'm not treating it in an abusing sort of way.

Yeah, turbos are way more complicated in comparison. That type of power from something that is bolt on, albeit not a simple bolt on, is alluring.
 
Guy at my work was talking about when installing turbos or superchargers you need to make sure your engine is pretty solid.. or you will blow something out.. I know our 4.0s are pretty dang tough, so my question I guess is for Chris or anyone else that has installed a supercharger..

Did you have to do any rebuilding when you installed it? How long have you had it/ how many miles is on your Jeep? Did it cause any mechanical problems for your Jeep since you have installed it?

Just questions I have been pondering, my rubicon has 117k mikes.. so it’s relatively low compared to many I have seen out there..


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Was looking at an APR modded Golf R last month... but wife wanted a jeep. So we have a jeep (not complaining).

Hahaha, understood. Both are awesome, but in such a different way. When I'm driving one and then hop into the other, its like stepping into a different world (even more so since my Golf is an auto and the Jeep is manual). I had the bug bad to buy an R about 6 months after buying my Golf, but those desires all subsided after lowering a bit, upgrading the turbo etc. Still, it would be nice to have AWD for winter and launches, but you also take a hit on fuel economy. Now that I have my Jeep for Winter, I'm not sure I want to drive it in the salt/snow since I plan to keep it for a while. First World problems LOL.
 
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