EDIT- It's been quite the long and winding road, but there's a happy ending! If you don't have time to review 100+ posts, skip to page 6 and digest posts 105 through 109, where I've summarized under the following categories:
Post 105: "NO, you don't REALLY have VTEC on your Pilot!"
Post 106: Build Sheet & Budget
Post 107: Swapped motor control options and wiring
Post 108: Mechanical swap itself, lessons learned & instructions
Post 109: Tuning, end results, and possible way ahead.
Reader's Digest version: I put a 3.7L dual-VTEC Acura TL motor into my 2014 Pilot 4WD Touring. It cost about $7,500 in parts and labor, but could have been done for around $3,000 if I'd done ALL the work myself and not done some of the extra parts upgrades. She makes at least 70 HP and 13 ft-lbs more torque than stock at the crank on 93 octane, and there's probably more still to be had (though I'm not going to go chasing it). It was sometimes frustrating and sometimes fun, but mostly I'm glad it's done and running like it came this way from the factory. GOBS of torque down low, and she'll cruise up a long hill at well above the speed limit in 5th gear without batting an eye.
-------- TL: DR version follows... buckle up, buttercup!--------
Well, the wifemobile (bone stock 2014 AWD Touring) threw a timing belt at 110k, just about 5k miles after having all those components changed with brand new OEM parts. Sheesh.
I'm always looking for an opportunity to make lemons out of lemonade, so since a used 3.7L J37A4 is within a few hundred bucks of a stock 3.5L replacement, let's make simple shit hard and see if we can squeeze a few more ponies out of Princess the Pilot, shall we?
Following a similar swap over on the Ridgeline forums as a guide, it won't be easy but it won't be impossible, either. Mechanically speaking, they're practically identical. EVERYTHING will have to move over from the stock 3.5L, down to the engine mounting points. All accessories and wiring harness. The wiring harness will have to be modified as follows:
1) Injector plugs are different from the 3.7 to the 3.5 so those will have to be moved over from the donor harness.
2) 3.7 has the VTEC solenoid and oil pressure sensor down on the block by the filter as opposed to on the heads like the 3.5, so the harness will have to be extended/modified accordingly.
While we're at it, I'll add a few goodies such as intake manifold spacer & thermal gaskets, throttle body spacer & thermal gaskets, High Flow Pre Cats, equal-length J-pipe, and ported lower intake manifold runners. If Princess has to undergo open heart surgery, we might as well do some touching-up while we're in there, after all!
My biggest concern is CONTROL. Fuel trims are likely to be way off as the 3.5's PCM tries to control an engine with larger displacement and larger injectors than it's expecting. I've got two options: 1) Swap in a Ridgeline PCM, which can be tuned with kTuner, or 2) Try a piggyback ECU (I'm eyeing the AEM F/IC 6). I'm leaning towards the latter.
Anyways, the block is on the way to the installer and all the other ancillary goodies are on order. We expect to start tearing into this around the beginning of September. I'll keep the forum posted, especially considering the dearth of info out there about performance modifications for our beloved Pilots!