I found a 2.0 engine out of an Aerio to replace the puked one in the GF's '02 Tracker. Everything's switchin' over pretty good except when I got to the Tracker's orange injectors, they seemed noticeably smaller than the Aerio's red ones I pulled out. Is there some color code thing when it comes to injectors? I plan on swapping EVERYTHING over as is. Don't wanna experiment in this case, but I'd still like to know the difference.

Is there some color code thing when it comes to injectors?

Usually there is a colour code but it may be manufacturer specific, there is also usually a manufacturers part number on the injector, something like INPXXXX. You can look up the details here:

http://www.witchhunter.com/injectordata1.php4

Too cool! Thanx for the info. I searched the HP ratings of '02 Trackers (127) and '02 Aerios (145+ -). I guess I found out one way they tweaked more HP out of an identical motor!. I'm keeping the big injectors for my build! 

145 HP is a pretty good # for a Trackick!

Too cool! Thanx for the info. I searched the HP ratings of '02 Trackers (127) and '02 Aerios (145+ -). I guess I found out one way they tweaked more HP out of an identical motor!. I'm keeping the big injectors for my build! 

Fitting bigger injectors isn't going to give more power, it would just mess up the fuelling. The difference must be in the manifolds or internal.

Compression the same on both ( I mean the ratio, ie: 10 to 1, vs 9.5 to 1) ? 

Rhinoman, I'm running bigger injectors on my 16v turbo engine, and it doesn't seem to have any fueling issues. I've read that this is not necessary though, as Sean at Aftermarket 4x4 turboed his 16V using the STOCK injectors with good results. Maybe I've got overkill, and am wasting fuel.

I have both manifolds, they're very similar, BUT not the same. I haven't measured the throat opening, but it's close. Perhaps the difference is "volumetric" which could enhance flow characteristics. I had always assumed bigger meant faster at least with carburetors it does - up to a point. So I guess we'll have to see if the Aerio motor is stronger with just the Tracker injectors. Now I just gotta see if these big Aerio injectors fit in a 16 valve! Just for experimentation of course, I would never want to screw up the atmosphere with rich emissions or burnt rubber for that matter!

Compression the same on both ( I mean the ratio, ie: 10 to 1, vs 9.5 to 1) ?  

Rhinoman, I'm running bigger injectors on my 16v turbo engine, and it doesn't seem to have any fueling issues. I've read that this is not necessary though, as Sean at Aftermarket 4x4 turboed his 16V using the STOCK injectors with good results. Maybe I've got overkill, and am wasting fuel.

It would be interesting to see what your fuel trim values are, I'm guessing that they're maxed out. Have you got a Wideband O2 set up?

I have both manifolds, they're very similar, BUT not the same. I haven't measured the throat opening, but it's close. Perhaps the difference is "volumetric" which could enhance flow characteristics. I had always assumed bigger meant faster at least with carburetors it does - up to a point.

With a bigger carb you get more air + more fuel, with bigger injectors you get same air + more fuel. The ECU will sense that the mixture is rich from the feedback from the O2 sensor and will try to compensate by reducing the injector on time but usually it only has a limited range of adjustment.

Wideband 02 Set-up? (Uh-oh, looks like I better go up one forum ) Uh no Rhinoman, I don't think I have this. Whatever it is. I guess when I used the word "volumetric" you thought I might know what I'm talking about. Fooled Ya!! I forgot about the more air part. I'm the kinda guy that would try just drilling holes in the manifold. I still haven't checked the #'s against the chart on that site. If the Aerio injectors ARE bigger, what would you suggest I do with them? (careful now!)

Actually Tone, I think he was replying to my question. Sorry for highjacking your thread man.  Now to answer your question Rhinoman, no I don't have any type of wideband sensor or reader. Couldn't afford it. But I'm pretty sure it could be better.

And hey Tone, what's with all the big words anyway?  "volumetric"?   This is "dumpster garage",   Not monster garage!

Oh....so that's what that purple section that says "quote" means, duhhh....
 

Actually Tone, I think he was replying to my question. Sorry for highjacking your thread man.  Now to answer your question Rhinoman, no I don't have any type of wideband sensor or reader. Couldn't afford it. But I'm pretty sure it could be better.

And hey Tone, what's with all the big words anyway?  "volumetric"?   This is "dumpster garage",   Not monster garage!

Hey while I'm on here...I still have the pics in the camera, but today I did some side by side comparisons and we may have stumbled onto something here. The Aerio intake opening is much larger than the Tracker's ! I'm betting that if someone had a 2.0 and wanted an almost 20 HP bump that they could swap on Aerio injectors and intake! If the old engine survived the interference when the T-chain broke, I'm gonna rebuild it. Rhinoman, the 'puter hook-ups look the same, how feasable is this? Someone mentioned to me that after '03 the Trackers had 145 hp, True? Gotta check this out.

You will need to check the schematics to ensure that the ECU pinouts are the same, if they look good then you shouldn't have any problems. Good find.

Here's the comparisons, the bigguns are the Aerio's

Can you give us the part numbers from those injectors?
Cheers
James