davidsali

For the neophite here; are there any disadvantages to a supercharger?
How does it affect gas milage, top end speed and off the line speed? Are there other modifications that have to done because of it?
Do you have to regear a 07' Rubicon Unlimited if you add it?
Approx. cost with installation?
Thanks to all for comments.
David

AndrewZ

I came from corvette modding and know a tad about superchargers..

I am not completely up to speed on the Avengers,but I will try to answer your ???

The avenger I believe is a screw design as apposed to a belt driven centrofugal.Imho the screw design is better and more efficient because they cause less parasitic drag on your motor..

The advantages are power when you want it,stock behavior when you don't have your foot in it..Most sc vehicles feel the same as stock until you step on the go pedal..

Disadvantages are more cylinder pressure inside the combustion chamber and shorter life of the motor due to the extra stresses on all components(not drastically reduced life,but some)..Added heat produced by the supercharger and some extra maintanence and tinkering always involved with modded vehicles..Added driveline wear associated with more power(clutches,u joints,synchronizers,etc all have a shorter life span in general)

Gas mileage on a JK application would most likely stay about the same and maybe even improve ,because the added torque would move the JK more efficiently off the line and under acceleration conditions..As well as give you a whole new computer program that would probably be better than the one the JK came stock with.Off the line speed and top speed would all drastically improve as long as the top speed was not computer limited..HP and torque would improve across the rpm range..

You don't have to add anything other than the kit provided which usually includes bigger fuel injectors,computer prigram,and all other necessary hardware to install it..Most folks add a high flow intake and exhaust to maximize efficiency..

I would not think regearing would be necessary,but you may want too, to get the most acceleration out of your SC.

I do not believe they have released pricing yet,but my guess would be near $4000-$5000 for the kit and another $1500-$2000 for a proffesional shop to install..

Prices are all guesses..Depends on the dificulty of installing on a JK..

I would install myself and save the $$$, as they usually are not difficult with the proper tools..

Later

MJS_Jeep_888

Wow - That's insane $$$... but a lot cheaper than paying $15K for a HEMI swap... still, OUCH.

I wanted a bit more pep, so I threw on the AIRAID CAI, and will have my exhaust redone when I have some cash to blow (if the lift bug doesn't bite me first, that is); together, those two mods should be good for at least 20 hp (on a dyno ). The only other performance upgrade I'm aware of (that's available yet) is a JET chip, but I don't expect to ever use it, because I don't want to have to run premium fuel in this guzzler...

Here's an alternative: if you're just looking to improve all-around performance, you can save yourself several thousand $$$ and get the aforementioned mods (<$1K), and then get re-geared (~$1K installed? I think)... the CAI and exhaust should net you 1-2 mpg better than stock, but the higher gearing will cost you in that regard... so maybe you'd come out about even, fuel economy-wise, and end up with a much more powerfully-performing Jeep... one that's ready to accept some big tires without turning into a dead snail on the road.

Anyone with more mechanical aptitude than me care to comment on the proposed, above?

woolf

Regearing and adding exhaust/CAI will not be able to produce the same driving pleasure the Avenger will give you. For the price of the kit, you get a lot. Everything needed for it to work will come with the Avenger kit. The big advantage with this kit is that the tuning will come directly from DC. Great kit, had one on my TJ, and would recommend it to anyone.

Torrin

I still do not understand why you would supercharge a JK? It is not designed to be a street drag machine and unless you DROP it (OMG DROP A Jeep!!), your platform would become less stable. Superchargers a very hard on a motor and you might be looking at replacing your engine after 50k miles.

Unless you are looking at doing extreme rock climbing, you should not need a ton more power and if you are doing extreme climbing, replace the motor (along with most of the rest of the suspension, drive train, etc)

Just my opinion.

MJS_Jeep_888

You're absolutely right - I thought this went without saying, which is why I didn't say it.

I was suggesting that you gently work with what you have, rather than stressing the engine severely... granted, a supercharger will net you 50hp easily... but what are you actually using that extra power for? If you're trying to build a street machine, go for it.

If, on the other hand, you're offroad-biased and are going to be turning some big tires and want more torque, regearing can recapture a "stock" (or even "sporty") feel for your JK... which is all I was saying.

MJS_Jeep_888

I'm curious: how reliable is a non-factory supercharger, typically? I've been told many times from "car guy" friends that superchargers are much more durable and long-lived than turbos are, but how long would you expect a well-built SC like Avenger to last? I think that the 3.8L is capable of putting out far more than the Wrangler is squeezing out of it, so I would expect that the engine would last well into the 100K range, supercharged or not... after all, it's not like you're throwing 30psi of boost into it!

I'm pretty happy overall with the 3.8L's performance in my 2-door, but I'd like to have a little more punch on tap at highway speeds... but the wife could never be convinced of the need for a supercharger... Or could she?

Jasson

I've been thinking of going this way myself. I'm used to having V8 power so the JK feels week to me. In the past I've been driving an '04 Grand Cherokee with plenty of V8 power and a 1973 Ford Bronco with a fuel injected Mustang GT 5.0 in it, and it's nice to have that power if you need it. When your pushing 250-300+ ponies it doesn't take as much gas pedal to get from point A to point B especially offroad.

Reliability is a factor though. So, for me, I'm trying CAI, exhaust, and new gears first to see how it does. If thats not enough for me I'll have to decide on HEMI or SC also, because my Unlimited with the lift and 37s is a dog right now. :sad: Once I get all that done I'll post my thoughts on that.

Because of the expense of the HEMI conversion I'm leaning toward the Supercharger, as of now that is.

Good luck, I'll be watching this thread to see what everyone's experience is. Power or lack of, is a big issue for me.

MJS_Jeep_888

Wow - you're running 37's with stock gearing? I BET it's a dog! What's your re-gear plan - 4.88 or 5.13?

Jasson

Mine came with 4.10. I plan on changing gears soon. One thing at a time you know. I'm not sure which I'm going with, but I'm thinking 4.88. I'm not going to rock crawl the crap out of it, mostly trails, some hills and exploring the surrounding territory. I do like to be prepared for what the trail throws at me though. More Horsepower would help my cause.

And I will have MORE POWER!!