Hey fella's, 
My vitara has only felt a little power sap from daily driving with 29's.  But going camping in the mtns with, gear, dogs, and kids seems to tax out my little 2.0L!  So far the only things I've added for power is a K&N drop in filter and replaced the stock muffler with a $20 turbo can. Is their any thing else I can do like redo the exhaust or add electric fans to get some more UMPFF! Or is extra power a lost cause? 

Best thing you can do to improve your ride all around and get noticeable power and torque back is to install the sidekick 5:13 gears.

When I increased the exhaust a bit I noticed a little increase.  My wife and son hate the loader exhaust (I'm guessing your a convertable too) so maybe not the best idea for family harmony.  I would'nt suggest it unless you needed work on the exhaust anyways.

I notice a big difference swapping to the 5.13 gears (I have 29" tires too).  Before it felt like I had to be speeding on the highway to make 5th gear.
Now it's totally different.  When I'm FULLY loaded (camper and family) I have the extra umph in the low end and still can use 5th a bit in the high end.  Daily driving, the rpm's a bit too high if I speed on the highway, so it helps me not drive too fast.  I've heard the if I get 31" tires the performance would be closer to stock.  I firgure that if I wanted to I could move up to 32" or 33" tires with only a little loss, similar to what your experiencing now (I hope).

So, short answer if you're not heavy foot on the pedal and may whant to go bigger in the not too far future, 5.13 is a great way to go.  Specially if you consider the potential problem in the front diff.
 

Im not planning on bigger tires for awhile unless someone wants to trade I have 95+% tread left.  I am a slow driver so I'm thinking new gears are a good idea.  Are 5:13 sidekick gears stock or aftermarket?  I can get a complete sidekick rear axle for $50 just gotta find a front. 
Also I have a 4 door (closed top) so exhaust sound doesn't matter much.  I can barely hear the turbo muffler I have now over the sounds of my Calmini Suspension!  Whats the size pipe would be good for the 2.0Ls?  I see most the 1.6L kick guys run 2"..

Thanks for the advise guys!
James     

I think it's 2 1/4".  Because of the noise and family issues I had to put on a little muffler as a resonator, the stock system had a little resonator at the end anyways.  Do a search here for pipe size, others have asked the exhaust size question and gotten lots of opinions.

The 5.13 (also listed as 5.125) are stock.  You can find them in most of the Sidekicks. I used the diff's from a 1.6L '98 and it's been working fine, the article says to not use these but nobody seems to know why. 
The swap is pretty simple, just follow the instructions.  The front diff is the same, just bolt on the brackets from you existing diff to your 'new' diff and slide her in.

My anvil/housing for the front diff was all aluminium, your's might be steel.  You could put the ring & pinion in your steel housing ($$), or just keep it for a spare (or sell it here to someone who pushes there tracker way harder).

When your all loaded you'll love      the difference the change in gears make.
I did not notice a big change in fuel use, but my commute is not very long and I have not put pen to paper to figure out my litres/100km.  I try not to drive over 110km/h most of the time (60mph is about 104km/h) and the RPM seems to hum along fine.

 http://www.zukiworld.com/month_030104/feature_tsb_shiftontheflyremoval.htm

Opps, I meant 1.8L (the one that they say not to use) not 1.6L like if previously mentioned

Thanks for the info JayInBarrie.  Between this and the newer rig thread I think I have a good grasp of what I need to do with the gearing now!   I'll search for the pipe size threads..

Hey Jay In Barrie, when you swapped the gears in the front end, did you swap the whole axlehousing and eliminate the air-actuated shift on the fly, or did you only swap the 3rd members? I'm planning on regearing my 2.0L when I get my 31's on, I just want to do it the best way.

I did the whole housing.  The brackets from the stock housing bolt right on to the '96-'98 housing.  It looks like Suzuki kept the same pot and housing and just changed the brackets to fit the Vitara.

I've read that '02 or '03 have steel pot and/or housing.  Mine being '99, it's all alumium.  I found it easy to slide in the 'old' pot/anvil and 3rd member/housing as one peice.  I'm sure you could put the 3rd member in without removing the pot/anvil, but I doubt it would be easier (working under a car is ackward, tight, and dirty as it is).

I've kept the old peices in case I ever brake one.  Murphy's law, if I keep it I wont need it.

Today I replaced my stock air intake box with a cheapo spectre cotton/oil cone filter and it seems like a decent improvement..  The zuk was idling at a lower rpm, ran a bit quieter, there was lot less noise when the auto trans shifted, and there seemed to be a little bit more power behind the pedal.. total cost $25 bucks.   Is the stock setup real restrictive?

(mashed the filter alittle inserting the IAT sensor)

Anybody know what this is?!  Think it would help airflow if removed??

I just replaced the filter with a K&N filter and noticed a difference.  It's a nice cheap improvement.

That little bulb is suppose to help keep the air intake quite.  A little resonator chamber.  I have not heard that it makes any difference with performance on or off, so you may just want to leave it on.  Saw a similiar one on a friends old Sonoma.

If you do the diff swap you can use Sidekick locking hubs or new locking hubs.  When locked you can still shift between 2wd and 4wd, just when unlocked your front wheels wont engage so you'll only be in 2wd regardless of what you put your transfere case too.

Try and find a Japanesse diff if you can.  I've used the Canadain diff and all seems ok, but the article say NOT to use these.  I'm kinda waiting to hear if I'll have to tweak, fix, or replace my diffs.  I'm not too hard on my Tracker so hopefully its just a small issue that I'll never have to worry about (knock on wood).