My next question for those that have them is the supercharger, first is this something a semi mechanically inclined could do, or do you need a computer and / or special tools to "reprogram" something? or is it just better to let the dealer install one. next question is, several friends have had turbos on non Toyota vehicles and they said and showed me the fill up slips, dates, mileage etc, that they were getting close to 50mpg on a turbo'd Volvo of course he drove it sane and kept his foot out of it. said he really noticed a huge boost on the freeway. can one expect any kind of mpg gains from a supercharger? im not talking a huge amount but 4-5 would be nice with sane driving. and im talking get your foot OUT of it and drive normally. i.e. nice and easy.
next question is does anyone have a supercharger with a snorkel? how well does that setup work? any problems? any gains with both on there?
Again thanks go out to you all!!
I am only semi-mechanically inclined and I installed my own. This is on a 3.4L engine, so I can't speak to the 4.0. But as an example:
Here is the stock 3.4:
and here is the supercharger by itself:
You basically label and remove a few vacuum lines, remove the throttle body and intake manifold and replace it with the supercharger assembly. Then you bolt the throttle body back up, attach a few lines and put the belt on.
Here's what the engine looks like at its most torn-down state:
and here it is finished:
I thought it was a fun and easy project, but your mileage may vary.
Don't count on getting better fuel economy with it. It takes 1/5th of a horsepower (when it's in vacuum) to run it, so technically, it adds drag. In the real world, my mileage did not worsen at all, and I know because I check my mileage at every fill up. But you do have to run premium. And as I experienced, you may find your mileage go up a little when climbing mountain passes because the volumetric efficiency is higher and it doesn't have to work as hard. But it would be best to sum it up by saying "your mileage won't change if you drive reasonably and it will go down when you're flogging it."
Saguache--there isn't much complexity to a supercharger assembly. It has a couple of gear-driven rotors inside that are spun by a belt. Supercharger failures are rare and even if you remove the belt all-together, the engine will still run fine. Likewise, if you were in Mexico and found only 85 octane fuel available, you can zip-tie the bypass valve open and it won't make any boost. It has no external oil supply or liquid cooling like a turbocharger, so there aren't any real fittings to leak (like in every single turbocharged car I have ever had). The supercharger is completely self-contained.