Okay, most of the posts I've ever done on here are for answering questions, not asking.  I've searched for a bit, but cannot find anything definitive on the subject.  I have a 96 Tracker with the 16v engine.  I've really been looking into the turbocharging threads, because it seems like the cheapest, most straightforward plan as far as moderate hp gains, minimal actual modifications, etc.  Anyways, this last Friday I get a wild hair and figure it's a good idea to know that the platform I'm going to be modifying from is solid, so I go to do a compression test, make sure everything is within spec.  Let's just say I was a little disturbed by my findings!
 
Cylinder 1: 150 psi (dry)
Cylinder 2: 130 psi (dry)
Cylinder 3: 160 psi (dry)
Cylinder 4: 60 psi (dry), 90 psi (wet)
From what I have read, around 180psi is what you should see, if my sources are correct:) 
My Tracker has 198,000 miles on it, and smokes on start-up.  I figured that it needed valve stem seals, and that compression would be a little low, but cylinder 4 really suprised me.  It just had a new head gasket before I bought it 2 years ago.
 
 Now, what I'm basically toying with is honing/deglazing the cylinders, and putting new rings in it.  However, in light of the fact that I'd like to turbocharge it someday, I'm now kind of at a fork in the road.  Keep it stock, or upgrade now while I'm already in there?

So my questions are these: 
I've seen and read that Honda d16 tuners are using Vitara pistons to lower compression on their engines.  Are the aftermarket pistons labeled "Vitara Honda Turbo d16"...etc. basically the same piston that I have, or is it a different piston?  On eBay there are some by Nippon (never heard of them, but...  that come with the pistons, pins, and rings.  They say their forged and all that good stuff, so I wondered if they would be a good alternative to stockies.

Second, with the previously mentioned pistons, they are advertiesed as "low compression, 8.5:1 pistons."  I know that's for the d16.  For mine, will it still be stock compression?  Or close to it?  Higher? Lower?

Third, if they work, do I need to use OEM Tracker rings, or will the supplied rings work in my 16v?   

And lastly, if these pistons are okay to use in my 16v, can I (or more importantly, would you recommend) run these pistons without turbocharging it right away?  My concern is that if it does lower compression, that it wouldn't run well enough for everyday driving.  Wildgoody, i know you've been down this road just from reading all the threads, but I'm sure there's a lot more people that have some info too.  I'd really appreciate it.  Here's a link for the pistons from eBay:

http://cgi.ebay.com/ebaymotors/CIVIC-VITARA-TURBO-PISTONS-D16-SI-RINGS-ZC-D16Y-CRX-/150606170595?pt=Motors_Car_Truck_Parts_Accessories&hash=item2310d3c9e3

Again, I'd really appreciate any and all comments on this! 

Unless your planning on pushing a lot of boost through your engine, IMO, I'd stick with the Stock Suzuki replacement pistons. From my own experience I can tell you that your not going to be on boost much of the time, so when it isn't, which is going to be the majority of the time, you want the engine to still make as much power as a stocker, at the very LEAST. You can get a considerable boost ( no pun intended)  in useable power with as little as 5/6 lbs using all stock components in your engine, and still be quite safe. If you lower the compression too much from stock, you'll lose a good bit of power everywhere, and only make decent power when the turbo is spooling.
I built mine for practicality and reliability, not maximum hp. It makes plenty of power to turn 32's and run down the highway as fast as I want without slowing down on hills, and I'd run it against anybodys Trackick, with the exception of Jlucks Audi Turbo powered rig, for comparison. If your goal is to make max HP, then you'll have to do more than pistons, crank strengthing, rods, etc. I think mine is somewhere around 150/160 hp.

Yeah, I agree.  I'm not looking to really push a lot of boost.  Like Wild and you say and have said, 4-6 lbs is all I was looking as pushing as well.  I just figured that since I was already there, now would be a good (great) time to strengthen any weak points.  I guess my initial question still hasn't been answered though.  Are those eBay pistons the same as stock, just a forged version?  Or are they a whole other animal?  And would you recommend I do new pistons and rings, or just new rings on mine?  I appreciate it again. I'm excited about the possibilty of a turbo Tracker.  Kind of one of those things you dream about, but once it becomes a possibility to be reality it really starts to get ya goin'!  Hehe...

Those pistons on E-bay are not forged, they look like stock cast pistons
to me.

The stock pistons will take 5 PSI no worries, but keep it 5 or below, and
get it an intercooler.

The reason these pistons lower the compression in a Honda engine is the
CCs in the Honda head are greater than the Suzuki engine, and the wrist pin
to crown of the piston is shorter than the Honda pistons, about .050" both
of these contribute to the over all lower CR in a Honda engine.

The stock compression ratio of a Suzuki engine is still OK for turbo applications,
depending on who's specs you use it's 8.9 or 9.1 both are OK for 5 PSI

In my opinion you should just hone the cylinders and re-ring it, I did the same thing
to my 8V engine first time around, my problem was getting enough fuel down the thing
because of the TBI design, the 16V solves the issue and works really well right out of the box

Get a new oil pump, and put a oil PSI gauge on it, the light will tell you when the engine is toast
and not before

Wild
 

Out of curiosity, have you clocked your 0-60 time with your turbo?  And about the oil pump, are you just recommending I replace it while I'm in there as well just for preventative maintenance?  Thanks for all the info.  Great stuff.

I never have, but run offs against other Trackicks I've just left them behind in a hurry, and keep pulling away. That's running 32x11.50 BFG AT K0's. Wild has run his on the strip and returned some pretty impressive times and top speeds. It really is worth the effort.

I blew a turbo from a defective oil pump blow off valve,
this is why I said replace it and get a gauge for the pressure
and as far as speed, under my avatar, 93 MPH 1/4 mile speed
this was running on 30" tires and 5.83 diff gears and 8 PSI boost
I was having ping trouble because I had no intercooler, so I will
also tell you to do that too as part of your build.

I toyed with low temp thermostats and extra fuel with a 60 gal
per hour nozzle, no amount of high octane extra fuel and low temp
stat would cure the pinging, the intercooler solved it right away

Wild

Sounds like fun!  Whether this will all happen right away is yet to be seen, but I'm pretty stoked about the possibilities.  I'm probably looking at running a top mount intercooler as opposed to a front mount.  Less plumbing to route.  Get a nice little hood scoop put on, and let her fly   I'll take that oil pump into consideration when I get it apart.  I'm not turning anything big, just 235's, but every little bit of oomph helps!  And I'm sure that just re-ringing is going to be a big difference.  The crazy thing about the whole situation, is that my Tracker runs like a top.  A little underpowered, but my 8v I used to have ran about the same.   Unless you did a compression test, you'd almost never know it had internal problems.  I sure didn't! I think God was  looking out for me by prompting me to do a random compression test, because I didn't even want to do one.  I just felt that I needed to.  Thank you, Lord!   

Well you already are on your way to low compression, just drop a turbo on it and
enjoy the ride, you can save as you ride to rebuild the engine when you have the
chance, or get another engine to build on a casual basis and drop it in after it's
done, gives you some time to tweak the system now and get it ready


 

What size turbo are you guys running?  I have all the FI stuff from a WRX laying in a box right now, intercooler and all, but that is from a 2.0 motor, think it would be too big?

I use meth injection on my SC BMW and it works out very well, has anyone added meth to a Samurai?

I'm running alcohol/h2o injection on mine. 

I run an IHI turbo from a 1.8L 80s era Subaru, but there are so many
that it would be hard to say which one is best, but generally a turbo
from a stock car, but not the super high performance race type cars
will do a good job and not lag if you keep in the 1.6 to 2.0 engine size
donor vehicle.

One of the good things about the turbo I used is it is set to 5 PSI stock
on the old Subaru because they didn't have an intercooler

Wild

check your local craigslist. around here complete stock (good) turbos can be had for 1-200. I would try to find one with a popular flange. like a T3 T4 T25 etc., could make future upgrades a bit easier.

Yeah, like I said I have all the turbo goodies from an 04' WRX, intercooler, down pipe, the whole bit.  Plan was to use it on my 2.5 Subie swapped into a Porsche 914 but if I can get better use out of it in the Samurai then maybe thats my best route.  I'm hooked on lightweight cars with decent power, hence the 914 (2100 lbs) with the 2.5 NA EJ25 subie motor at 175 HP, thats in the HP/weight ration of a Lotus Elise... 

Hey Wild, (or someone else with the know)
In another thread recently you talked about forged pistons to someone looking at a possible swap/turbo upgrade.  Does anyone actually know of a place where we can get FORGED pistons?  I know that 5psi is more than no boost at all, but I'm really seriously looking at rebuilding my engine now, and since I'll be there, I'd rather upgrade to something that'll handle 10psi or so.  Forged pistons would do that, wouldn't they? Thanks!