NP, its cool!!
With the weather getting colder I likely wont be doing much in this area.. I'm going to try and find the highest unleaded octane fuel that I can and prove out that the ECU does or doesnt account for any higher octane then 93ish.
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AFAIK the ECU has no idea what octane fuel you're using... all it knows is if it's knocking or not.
So if you're not knocking on 91 (and shouldn't be) I can't imagine why "higher" octane would do anything for you at all.
Cooler intake charge sure, but you're not going to get anything from the octane boost unless the car is knocking on pump gas, which it shouldn't be...
I'm kinda having a hard time with this subject. All thats being done is cooling the intake air. I know thats the idea and can see how a big differance can be made on a 100 degree day. But anything below 50 degrees I would think this would be a waste of time.
There is almost no chance of the computer adding timing. So the only gain factor is A/F ratio change.
Kurtz- This ^^ A/F change would be noticed and adjusted. I agree that the knock sensor would pull timing and as much data logging as I've done with piggy back systems I have never seen a stock ECU add timing. Thus gains will be almost none.
I'm sure I would have seen 2-5% gain with my S/C setup but N/A on these motors? I'm not sold.
Originally Posted by jgbackes
In the old days, the MAF was a heated nichrome wire. The air passing over it cooled the wire and the ECU could compute the amount of air being delivered past the throttle body (TB).
If you put the meth/water (MW) injector in front of the MAF, will it notice that there is more/cooler air going past? One of the photos I saw put the injector after the MAF and before the TB. What's the best location?
Don't put anything across the MAF on the ISx50. Or you'll lose alot of power like 100%, lol / Tow truck / New MAF
When injector duty cycle is increased, timing is pulled.
The Toyota ECU also check the rate of rotation VIA cam/crank speed/RPM.
If the ECU see's a large gain in assembly speed it pulls timing.
Example: Normally at WOT the cars running through the RPM's at a normal pace. The timing map falls as the injector duty rises.
OK, so now you have wheels spin (traction off), motor speed rises faster through the RPM's. ECU see's change and moves your timing ACC to another point in the map. This is called 3D mapping.
Now your wheel spin stops mid RPM range and your car now bogg's and feels slower until the next gear change.
Reason: Vehicle speed is reduced, Timing is reduced and now your at a lower map point than design for good/great performance.
So let's look at the layers of mapping on the Stock ECU
Rotation of assembly VIA /CAM/ Crank
Air Flow /MAP
Intake Air temp
I'm leaving out about 3 more that are just to hard to explain without showing.
Now take these various maps and overlay them in a 3D format. (Think joy stick motion) Letting all of them work as one map. If one point changes then the map changes all the other points to keep perfomance SAFE!
Throw Meth injection into the mix. What do you think the ECU will do?
And what is your view of the change it will make? Make a 10% decrease in intake air temp. What happens to the map? Keep in mind the factory tune is already perfect 100%
**My thoughts** The only way to gain performance is to get outside the factory ECU mapping, your performance mod must be a greater gain then what the mapping will allow for.
#1 - Boost
**My point to the rant** Your gain will only be what is already locked inside your ECU. The gain is already there, all your doing is moving the DOT around on the map.