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With 5 speed tranny, its a straight drop-in. Use k20a2 wiring harness. Since you are removing the engine, this is the best time to also change your motor mounts, don't go cheap, and best time to upgrade the clutch and flywheel. With the k20a2 conversion you will need to use an RSX type-s headers; 2.5 inches vs. 2.25 inches. I am using a kpro v4, which makes everything easier.
For me, the A/C pump did not fit due to the subframe. Also the power-steering pump off the k20a2 is not needed, I used K-tuned EP3 pulley kit, The belt did not work for me personally, I used a 51 inch 7 ribbed belt. Also the k20a2 uses a PRB intake manifold stock. I used a RBC intake manifold (larger) from a 2006 Honda Civic SI. This can be a fitment issue due to the fact it rests against the front radiator support.
The best way is to slightly bend the rear radiator support out.
On the k20a2 engine harness, you will not need to use the coolant temperature plug to the radiator, the EP3 does not use it. Minor charging harness plugs were modified to fit on the K20a2.
Honestly, worth it, time consuming, but worth it. It took about twice as long as we thought, 4-6 hours turned into 12 hours.
I am curious to know why your A/C compressor didn't bolt up... it should work fine. You mentioned interference with the engine cradle... I wonder if your aftermarket mount set has slightly cocked the engine off axis (valve cover toward the firewall) a bit and this has reduced the space for the A/C compressor.
Sorry, it should fit on a normal swap. In my situation, with the hasport billet motor mounts, the motor actually sits lower into the chassis, clearance between the ep3 subframe becomes too narrow for the fitment of the a/c compressor. Also running a RBC intake manifold also takes too large of an area for the fitment of the A/C condenser.
Honestly, the K20a2. I have never been in a turbo EP3 but there are mass differences in the motor. The K20a3 has economic and different cams, no oil piston squirter, and compression is only 8.5 : 1.0, compared to the k20a2 which is 11.0 : 1.0. Lastly, you can add bolt-ons later, the motor is my first concern.
So I'm doing this swap and I see you say to use the a2 harness why won't the a3 harness work or will it work and you just used the a2 please inform me thanks
09-17-2015, 07:14 PM
My 2004 EP3 K20A2 swap
