Swap D15B2 USDM with D15B JDM

Like my subject says, I'd like to swap a D15B2 USDM with a D15B JDM motor. From what little I've found, this JDM motor can go into my 91 Civic DX, but I must use my throttle body, intake and exhaust manifolds.

All I want is a replacement motor. I don't care about going fast and furious, I just want to take out my blown original and get my car back.

There's conflicting info about the D15B that causes me to be a bit wary, however. Some say it is a VTEC motor with substantially more hp than my D15B2 (90hp vs 130hp). If it is VTEC, how will my ECU be able to run this motor. It's also supposedly MPFI, whereas my current motor is DPFI. These differences are pretty steep in my book and I'm trying to figure out if these motors are similar enough for a direct drop-in.

If anyone has any information I'd really appreciate it!

btw - the following link is the company I'm considering buying the motor from:

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Reply to
larson.joshua
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just call and make sure you order one that's year appropriate if you want stock replacement. the vtec will disappoint if you're not going to connect the gear to run it since the cam will be in "low performance" mode all the time. if you /do/ want to run the vtec, the electrical conversion is doable with the help of the folks at boomslang, but imo, it's still non-trivial. but the motor drops right in.

Reply to
jim beam

so, just a few questions.

1 - running the vtec is possible, but do you think i'll need a different ECU?

2 - does the vtec require MPFI?

3 - is converting to MPFI a pain?

4 - so the D15B JDM will drop right in (if i decide on a simple swap), using my intake, exhaust, throttle body and ECU?

i really appreciate your help!

Reply to
larson.joshua

to do it "properly", yes. there is an aftermarket vtec kit out there that will allow you to get around that - it will operate a simple vtec on/off solenoid independent of the ecu based on rpm's, but i've not used one so can't endorse. i'm also not sure if the odbI ecu's shift their cam timing around or whether that motor has multiple more than 2 cam profiles, but if yes to either, factory ecu conversion is the way to go.

for maximum advantage, yes.

yes! the mechanicals are easy - it's the wiring that's the pain. go to boomslang.com for the least brain damage solution.

it's going to cost you a fair bit more to do the conversion. vtec ecu's aren't cheap. the conversion wiring kits aren't cheap. the 4pfi manifolds, throttle bodies, plumbing, etc. aren't cheap, even if you get them from a junk yard. you'll also be best advised to get the factory shop manuals for the patient and donor vehicles too.

yes. some of the motors have blanking plugs on some widgets that the japanese use that we don't, but other than that, they're identical. you don't mind japanese stickers on your engine do you?

call your vendor - they'll advise best.

my advice is that if you want this car for transport and it's your daily driver, just do the straight swap. if this is a second car, it's a science experiment, you're good at jigsaw puzzles, and you're good with wiring diagrams, it's fun to go down the 4pfi road.

Reply to
jim beam

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