AP2 swap into AP1 using 04-05 ECU?
#11
Correct. The AP1 gearing is designed to return to a powerband assuming you're shifting at 9K....but you'll be shifting at 8.2K if you're using a 2.2L and AP2 ECU.
A 4.44 diff gear should put you close to where an AP2 tailshaft reduction would.
I just figured the AP2 trans would be much easier since the engine and trans would already be out for the swap.
So...needed? No.
But Honda updated the gear ratios for a reason. Its not a cheap endeavour to redesign a trans. The 2.2 isn't a good pairing to the AP1 trans.
And yes...I'm aware that you *can* rev the 2.2 to 9K. But you also *shouldnt*
A 4.44 diff gear should put you close to where an AP2 tailshaft reduction would.
I just figured the AP2 trans would be much easier since the engine and trans would already be out for the swap.
So...needed? No.
But Honda updated the gear ratios for a reason. Its not a cheap endeavour to redesign a trans. The 2.2 isn't a good pairing to the AP1 trans.
And yes...I'm aware that you *can* rev the 2.2 to 9K. But you also *shouldnt*
The primary reduction gear in the ap2 trans in 1-4 gears is equivalent to having a 4.22 rear end pairing with the ap1 trans. I did the math on it many years ago when we had a accurate gear calculator on the car to work from. Likewise the ap2 trans is a better pairing with the F20 for the opposite reasons, because the F20 needs the help of a lower effective gear ratio to compensate for its lacking trq.
None of this matters enough to go through the effort and cost unless the swap already needs to be made because it blew up - which is why I did it.
Last edited by s2000Junky; 08-10-2020 at 04:38 PM.
#12
Yeah, I've also read that the 2.2 would've been perfect with the AP1 gearing and vice versa for the 2.0.
#13
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OP wants to use the stock AP2 ECU.
Even with the AP2 trans, shifting from 1st to 2nd at 8.2K puts you JUST outside of VTEC.
2 to 3 shift is on the borderline too.
With an AP1 trans, he's going to be way out of VTEC on 1-2-3 shifts.
And there is no benefit to lowering VTEC without using a HFC and test pipe. And you'd need an ECU.
I'd go for the full, easy solution and use the AP2 trans.
Idk why you'd want longer gearing in either of these cases.
There's advantages and disadvantages to using the AP2 trans on a F20.
And I'm sure there's advantages and disadvantages to using the AP1 trans on the F22...but IDK about this being ideal.
This whole thing is pointless...he doesn't need a swap yet. And where TF is he going to find a 2.2L nowadays?
Even with the AP2 trans, shifting from 1st to 2nd at 8.2K puts you JUST outside of VTEC.
2 to 3 shift is on the borderline too.
With an AP1 trans, he's going to be way out of VTEC on 1-2-3 shifts.
And there is no benefit to lowering VTEC without using a HFC and test pipe. And you'd need an ECU.
I'd go for the full, easy solution and use the AP2 trans.
Idk why you'd want longer gearing in either of these cases.
There's advantages and disadvantages to using the AP2 trans on a F20.
And I'm sure there's advantages and disadvantages to using the AP1 trans on the F22...but IDK about this being ideal.
This whole thing is pointless...he doesn't need a swap yet. And where TF is he going to find a 2.2L nowadays?
Last edited by B serious; 08-11-2020 at 11:58 AM.
#14
In California, smog shops will tag your car in the DMV database as an engine swap and force to take it to the Bar Smog Check Referee.The engine code is stamped on the engine and can be easily identified. You will need to pass as a 2004 or 2005 car depending on the ECU part number. You'll need to have all emissions equipment intact. Also, you'll need a matching Vin# in the ECU as well, which can only be done at the dealership for $350 or however much they feel like charging. After all said is done, you will get a sticker slapped by your engine strut mount to legally smog at smog shops in the future.
Best bet is reprogram the 2004 2005 ecu to match your immoblizer and encode your vin# into the ECU.
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