Honda J-series (V6) 3.7L swap (replacing 3.5L)... F/IC a good solution? | AEM
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Honda J-series (V6) 3.7L swap (replacing 3.5L)... F/IC a good solution?

Greetings, tuning gurus!

Long story short - the wifemobile (2014 Honda Pilot with a 250hp J35Z4) threw a timing belt just 3k miles after changing it.  I'd much rather "upgrade" than "repair" any day, so since the 305hp J37A4 is about 98% mechanically compatible, I'm considering a swap.  Changing over the PCM "brain" to one from a J37 would be problematic... VIN/immobilizer problems aside, the transmissions/drivetrains are considerably different and the PCM controlls BOTH the engine and the transmission.

This has me leaning towards a piggyback solution.  The only other source I could find for a similar swap was a guy who replaced the J35Z3 in his Honda Ridgeline with a J37A4... it ran well on the stock ECU under light loads, but fuel trims were off due to different sized cylinders and different sized injectors.  It seems that the stock ECU could use a little "help" getting those fuel trims corrected.  kTuner is a popular aftermarket tuning application for many Hondas and Acuras... including the Ridgeline, but NOT including the Pilot.  He was able to use kTuner to correct the trims, but I cannot... so that's where the swap similarities ended, unfortunately.  

My questions:

1)  Would the AEM F/IC 6 be "overkill", "underkill", or "just right" for this application?  I'm not going Forced Induction, just need it to run like it came with this engine from the factory.

2)  How difficult would it be to generate a base map and make the adjustments?  Unfortunately since the engine is already dead, I can't run the car with the bone stock 3.5L and log it that way.  I did read in the instruction manual about how to put in old & new injector size, boost, and RPM to create a base map, but I'm changing displacement and NOT adding any boost?  Would this still be an acceptable starting point?

3)  Any other thoughts or suggestions?

 

Thanks very much in advance!

 

-Jon