Installed Airaid intake, now mil on
Senior Member
Joined: Aug 2008
Posts: 4,778
Likes: 10
From: Douglasville GA
I also spoke with Airaid and they said there intake will not cause a lean condition in the vehicle and will Not run outside the f150's adjustable limits, which means it can adjust safely for the added air. So basicly I should have just asked them first lol. Thanks for advice anyway I do appreciate it.
x2. I guess the TSB and Ford tech's arejust b/s'n around, AirAid knows F150 3v engines better than Ford tech.
Thread Starter
|
Member
Joined: Apr 2010
Posts: 19
Likes: 0
i dont really believe the airaid guys but i do believe what the engineers told me. i am not aruing the fact that a lean condition will hurt the truck i am simply saying that not all lean conditions are harmful. plus the engineers who calibrate the pcm said the optimal setting for max performance that they can use is 12.3:1 - 13.6:1 a/f ratio. the normal running a/f ratio is around 14.2:1-15:1. they do admit that a slightly richer setting will gain a few horses but they cant set it that low because of emission standards. i will be getting a programmer soon in order to optimize my trucks performance anyway, but in the mean time i will run it with CAI and just monitor the system closley. oh, and since i followed the advice of the engineers the MIL/ check engine light has not returned and the system is running within spec.
Last edited by prophet136; Jun 2, 2010 at 05:07 PM.
Senior Member
Joined: Aug 2004
Posts: 2,824
Likes: 0
From: North Huntingdon,Pa.
Thanks for the advice. I did however run the dyno with out running the calibrator first (doh!). So after calibrating I ran it again with all the adaptives and keep alive memory reset. She ran fine showing a perfect a/f ratio of 14.3:1 threw out the rpm range the leanest point was at 3700 rpm at 14.8:1. The factory setting a/f ratio is 14:1 as requested by the ecu. Oh and by the way a a/f ratio of anything lower than 13:1 is considered excessively rich! If the truck ran something that low it would never pass California emissions and would not be certified for use in California or the us. The perfect stoichemetric a/f ratio is 14.7:1 and anything over 15.3:1 is considered dangerously lean for the motor. The ecu in the f150 is designed to, under certain light load conditions, to run a 15:1 a/f ratio for fuel economy. Oh, and just in case your wondering where I got my info, I know several ford engineers tbhat worked on the f150 and other ford vehicles two of them are powertrain and driveability engineers so it's credable. I also spoke with Airaid and they said there intake will not cause a lean condition in the vehicle and will Not run outside the f150's adjustable limits, which means it can adjust safely for the added air. So basicly I should have just asked them first lol. Thanks for advice anyway I do appreciate it.
Yall would be suprised how many stock vehicles run 14.7-15.1 under wot....
You have to remember, that number is going through 2+ cats... So the a/f is a bit lower then that coming out of the engine...
You have to remember, that number is going through 2+ cats... So the a/f is a bit lower then that coming out of the engine...
Senior Member
Joined: Feb 2004
Posts: 10,390
Likes: 10
No wonder they don't make any power with stock calibrations
Trucks are heavy - they need more enrichment under load than a car
The site is having problems uploading images at the moment, so here's a quick example of what a good tune will do on a late-model F150. I'll post the tabular data later. (underlines are to keep the fomatting intact - sorry, lol)
This is an excerpt from an on-road locked in 2nd gear run.
92 Octane per tune, with A/F's being measured AT THE TAILPIPE with an Innovate wideband and using their Bosch wideband sensor in their purpose-specific tailpipe clamp:
RPM___Speed___TPS %__LOAD__ ECT__IAT__A/F___Spark
0600______0______0____0.178__192___54__14.69__15.9 <-- idle (closed loop)
3577_____53____100_____0.89__194___50__11.94__16.7 <-- mid-Rpm (open loop)
5767_____96____100_____0.67__200___44___12.3__26.7 <-- max rpm (open loop)
So - OP, still want to believe those 'engineers'?
Airraid just wants to sell you an intake - they do not care. Just like Fartmaster tells you what you want to hear - a 'performance' system that really is just the opposite.
MGD
