Alright guys, short background info. My L15A1 ran for ~15 minutes with no oil in it a couple years ago. Metal shavings in the oil, and VTEC would no longer engage due to lack of oil pressure. 30K miles later, I think the motor is actually on it's last leg. Yes, I've run the poor L15A with a beaten up bottom end for 30K miles.

So it's time to replace the motor.

I know that the iVTEC motors make ~10hp more than the L15A1. My memory might not be serving me correctly, but the L15A7 has lift adjusting VTEC, instead of the 4/8 valve setup in the original motors, yes? If not this whole idea is a wash.

The idea is to throw the L15A7 in place of the L15A1 when I go to replace the motor. Obviously the "i" function isn't going to be served by the original ECU, and I'm not going through the trouble of changing it as well. But the newer motor should be a bit better even without it (if I'm not mistaken is a torque curve modifier only) - With me?

Thoughts anyone?

 

Any time you change motors, you grab the ecu that came with it. A k20 swap might be better. Honda Fit Photos K20 - Import Tuner Magazine

 

This would be a really complicated job. It would be interesting, but in my opinion for the effort, potential need for fabrication and lots of electrical modification.. it would definitely not make up for it with the 10hp bump at the crank shaft. Besides both A1 and A7 have very similar torque curves to begin with. But you are right in that the A1 cylinder head being SOHC and that it only has the on/off switch for 4 of the intake valves is inferior to the A7. However this inferiority would only really become pronounced as they are modified to produce more power.

But trying to make the GD ECU run the GE motor and interior electronics, as well as communicate with the GD TCU, and other peripherals would become an immense project and an even bigger headache.

Also I'll give you $50 + shipping for your trashed motor either way you go.

 

As I understand it, the "i" in iVTEC is simply the ECU deciding to raise and lower the VTEC engagement based on certain parameters. I wouldn't expect the A7's solenoid to be wired any differently than the A1's and I would also expect the rest of the engine electronics, crank & cam angle sensors ect, to be the same across generations.

I wouldn't be surprised if I had to rewire jumpers or sockets to get it to work together. I guess I need to pull up the parts documentation for both motors when I get some spare time and figure out what the actual differences are.

I wasn't envisioning any major wiring modifications or anything of the sort. Simply run the GE motor with the GD ecu and deal with the exhaust routing.

Ok, the part numbers for the cam and crank sensors are both different. My intuition tells me that the cam sensors are the same, but that the crank angle sensors are different.

($50 sounds good to me for a longblock)

 

You'd be better off just getting another L15A instead of the A7 and tuning it up. Unless you're already set on doing the A7. It is going to be a lot of trial and error and and a lot of work trying to get the A7 to run on an A ECU. The L15A is a better base engine in my opinion, I don't care for the exhaust port design on the A7's head.
Squeezing extra power out of the L15A is going to be much easier than rigging an A7.

 

Has anyone discussed the possibility of just a head swap?