I have a stock 2006 H3. So far I have had no problems with it except for some wind noise, battery died once and air conditioner stopped working once. I live in the Middle East and decided it is time to add some power to my machine. On Monday I am going to order-
Air Docs CAI
(Still trying to figure out which air filter I should use- any ideas? Does anyone use a non-oiled filter with an Air Docs CAI?)
Zoomer exhaust.
HPtuners with a tune file from PCM for Less. (Much easier than trying to send my PCM or do a core program plus planning to buy a H3T in about 8 months or less so will want to tune that one also)
Upgrading my tires to BFG A/T 285/75-R16 or BFG A/T 295/75-R16 on the stock wheels.
If anyone has any better ideas or sees any major faults with any of my choices please advise before Monday!!!!

 

I did a little digging myself and it looked to me like an intake wouldn't give much more HP for the money. The only upgrade I found worth the money for the HP was an exhaust, roughly 10% gain for about $500.
Anyone else, please chime in...

 

My thought is that both the intake and the exhaust should be upgraded for the most HP gain. Either one or the other will do a little, but by doing both you increase exponentially.

 

That was my initial thought, but apparently the H3 breathes in well. K&N claims 18.57HP gain at 6001 RPM. Who revs that high! A closer look at the dyno chart shows very little gain until you get over 4500rpm or so. Obviously, that's where the intake needs more air, but for maybe 5HP, $350 isn't worth it! Plus it tells me the H3 already breathes well on the intake side.
BTW - a couple years ago I purchased a cold air intake/exhaust combo for my wife's Miata, and they'd dyno'd the combination at a 15HP gain. The cost was $360. That's chaep HP! If I could get 15HP for my H3 for $360, someone please tell me where...

 

You have been looking at the wrong intakes apparently.

If you have a stock I5 H3 with no other mods, a CAT back exhaust will get you 1-5HP/TQ. More sound, than performance increase. 10% increase from an exhaust alone will never happen. MPG improvement too small to measure. $400-$900.00 depending on brand and materials (SS v Alumanized).

High flow filter itself, no other mods 3-6HP at WOT. MPG improvement too small to measure. $50.00

If you have the same truck, stock and no other mods, an intake and high flow filter can get you 1.5 - 2HP and TQ per cylinder starting at mid range throttle moving up. That is 7.5 - 10HP in a useable rpm band, 10-17 HP at WOT. MPG improvement 0.3-1.0+. $200.00

I've got 2006 H3 and Canyon dyno #s.
The LH8 5.3L with more cylinders responds a bit better.

Add the CAT back and intake together, they improve each other. Add a PCM tune, and you can take full advantage of an intake and CAT back adding HP and TQ, plus improved drivability through the auto trans selections in the tune (firmer shifts and better kick down programming). Easily 12-18HP with and intake and CAT back mods, and 8-12HP with no other mods. MPG improvement 0.5 - 1.5+. $230.00

IMHO the exhaust is not the best bang for the buck, not even close. Although it is still one of my favorite mods... absolutely. I do run a MagnaFlow CAT back on my 3, and sure do enjoy the exhuast note. I put on the CAT back as my first and only mod to see if I could tell any difference. Butt dyno measures exactly nothin, could not see any improvement in MPG either.

 

Well, that's the best explanation so far. So, an intake, Magnaflow catback, and a PCM tune...roughly $1000, gets me 12-18HP and 0.5-1.5 MPG improvement. That's pretty expensive HP! The MPG will payback in time though.
Thanks!

 

I always err on the conservative side. Really, if you do the big three (Intake, CAT Back, and PCM tune), you cannot add together individual performance increases, but you can blend them so they complimant each other.

With all three on the I5s, I would put the improvement at better than 20, but less than 30HP/TQ. It varies truck to truck, and more so on areas of the country (altitude, temp. and humidity), but that is close enough for a good understanding anyways.

 

A high flow airfilter should be worth about zero hp. But removing the lid and leaving it off might be worth a few.

A good friend of mine is an automotive engineer. I lent him my '06 H3 for a month or two durring the off-season (summer) and he data-logged the ECU with his laptop and ECU software.

He found that removing the lid changed the MAF voltage a good bit,..but removing the filter entirely didn't do much if any more. Therefore it would seem that the restriction is in the inlet to the airbox and not in the filter itself.

The filter is HUGE,..and has a nice velocity stack after it. I doubt there is any after-market intake out there that wouldn't be a step backwards. The downside is the intake makes a horrible noise with the lid removed, at higher throttle settings...which probably explains why there is a restrictive inlet into the airbox.



My friend also logged the ECU running higher ignition timing with mid-grade v.s. regular, but no change when going from mid-grade to premium. This would account for the improvement in mileage I got when using mid-grade. (I also noticed the detonation went away with mid-grade).



So my recomendations are remove the air-box lid and run mid-grade gas (if you can stand the noise. (The extra mileage will probably offset the increased cost of the mid-grade gas). Or better yet,...install a second inlet into the airbox. A 2-3" tube running from the front of the car to the airbox would have the same effect as removing the lid,..but without most of the noise.

Stage 2....get an ECU re-flash and switch to premium. You'll probably have to use premium because the flash will probably dial in more timing.

 

Thanks all for the great inputs!

Doc Olds- Thanks for explaining what I can expect. I was hoping for a 30 - 40 hp gain. I will be contacting you on Monday or Tuesday to order. Please recommend which air filter you feel in the best- so I can source and order it.

The most expensive mod will be the exhaust ($699 + $216 shipping), then the PCM tune ($499 Hptuners+ $150 for the tune file from PCM for Less) and then the Air Docs CAI.

Not very worried about MPG increases, as 97 octane sells here for about $.83 per gallon and 91 octane sells for $.72 per gallon.

I will figure out some way to measure the increases in performance with each mod and post the results here. Maybe 0-60 time (or 0 - 100 kph...metric system here!) and 1/4 or 1/2 mile times- each time I add a mod (Sorry no access to a dyno). It will be a minimum of 2 weeks before I start due to the shipping time, customs clearance and my work schedule.

Captkirk

 

Thanks Duckstu.

Doc Olds- Would the OEM air filter work on your Air Docs CAI?

I am not an expert on airflow, what is your take on the change of MAF voltage in Duckstu's post?

When I get my HPtuners software, I believe I'll be able to monitor it (even if I don't know what it all means!)

Thanks again for everyones inputs, I am learning a lot!