Hmmmm... then maybe dont reset the ECU, so you can get increased mpgs?
but...
not so good for emmisions.

I wonder if the emmissions is the major (not the only one though)diff that we observe with our USDM Fits mpg's when compared to others abroad (with regards to same engine and tranny)

 

This whole thing with MPG increases now makes sense. The OP did NOT make a bung for the IAT sensor in the intake tubing. It's hanging somewhere by the manifold.

The OP got his gains in mpg through engine running lean...not good for the engine....

 

Not quite...
The best way to experience gains in performance for mods like intakes, is to reset the ECU after performing the mod...that way, your ECU will adjust for the new mod, ie: different A/F ratio...

 

This might be a retarded question, but what does running lean mean, and why is it bad for the engine?

 

Running lean means too low of a fuel to air ratio just as running rich means running too much fuel to air ratio.

 

Lean means that there is not very much gas in the Air/Fuel mixture entering the engine. When this happens too drastically, the engine will "knock", or fire prematurely. That can ruin pistons, rings, valves, rods, etc...

 

Running Lean = Detonation, knocking...
Vtec engines have a Knock sensor that will retard timing if detonation is detected.

If your engine is running too Lean, you will experience bogging at WOT...loss of power.

 

the stock airbox may be getting cold air from the fender but the box sit over the radiator hose which is hot right.

 

That sucks if its running lean, but if you could make it work without running lean, the Mod its self looks nice, and clean, I can dig it. NEways

 

Congrats on your homemade SRI!

I made one a while back, too. Who needs to spend lots of money? I even have a K&N cone air filter:

***Also - on the not of IAT sensor - I did install it in the intake - see picture ***

 

The IAT wire is very short (maybe 2"). It was never at any point "hanging somewhere by the manifold".

I'm not an idiot. I've been modifying and racing cars since you were wetting the bed.

For the sake of argument, why is running a little leaner a bad thing? It's bad for a forced induction motor, right? Yeah. You want to run fat with a turbo, close to an 11-11.5:1 a/f. When I was tuning my AEM EMS on my 1991 Eagle Talon AWD, I was shooting for an 11.5:1 a/f on my AEM WB-O2. At 20psi on my GT30R and 20 degrees total advance, on 93 octane, I made 470whp. I would have made a few more horses with more timing, or leaning it out, but I would have reached the limit of my Precision 750hp intercooller and started knocking. So I played it safe.

But in an all motor setup, a lot of guys I've seen tune for 13-13.5:1 a/f. Running lean is not a horrible thing.
And regardless IF, IF the car was running a little leaner than before, this motor is a 1.5 liter, low compression, naturally aspirated motor making 85whp. Running 93 octane gas. I couldn't get knock if I hit it with a 10lb sledge!

And IF, IF I traded 5 whp, for 7 more mpg, WGAF? I'll trade 5whp on the highway for 7 more mpg anyday!

The sensor was reading air temps up near the top of the throttle body, under the hood. The SRI has a 90 degree bent tube with a total length of 6", sucking in UNDER-THE-HOOD AIR. I seriously doubt there was much of a difference in the temps at the IAT and the TB.

But, I mounted my IAT in the SRI today using a 5/8" hole saw bit and the factory rubber grommet, so we will now see if that helps/hurts.

 

And before someone asks:

Here is my 1992 Plymouth Laser RS AWD Turbo










And here is the 1991 Eagle Talon TSi AWD Turbo I was talking about above:












And a racing vid: MySpaceTV Videos: My Talon AWD Turbo vs 2000 Firebird LS1 by Jay Dog Photog

Both have been sold and gone for a while. Both money pits. The Laser made about 325whp and the Talon made 470whp on pump gas. On race gas, I woould have shot for 600whp. That thing on street tires would cut 1.5 sec 60' times and mid-low 11's in the quarter.

 

And here is where the sensor was sitting before I installed it into the bend. It was wedged in between another couple of wires, so it wasn't dangling around.

Not really anywhere near the exhaust manifold.

 

To the OP...

First, let me say sorry for offending you..There's no need to be defensive...
Second, I could care less what the F you do to your car....
Third, knowing so much as you do, wht don't you pull the plugs to confirm if you're really running LEAN...

Lastly, running lean is NOT good for the engine...running LEAN will lead to detonation...your knock sensor will sense that and the ECU will retard your timing...

SInce, you know about cars, "since I've been wetting my bed", why don't you tell me why that's a GOOD thing...

If it's good for you ....I'm happy for you...

 

Good call. I'll pull the plugs right now and check them.

And running very lean is not good, I agree with that. But this car is pig rich out of the box and running a little bit leaner is not going to blow it up.

We cool, mano.

 

Looks good. Nice and tan. No dimples or pock marks or metal droplets to indicate detonation. Very slightly oily on one side, but pretty much dry and clean for the most part.

I don't see serious damage happening with a clean plug like this.

 

If you're seeing white on the base of that ground strap, it's showing detonation. It should be somewhere in the middle...

 

Well, I just did this to my car this morning and my wife did it to hers about an hour ago. They sound nice and look good. Thanks for the idea!