I'm getting close to pulling the trigger on an F22 swap from an '05 AP2 into my '02 AP1 track car. 125k miles on the F22 with 240 compression and will perform a leakdown prior to swap. I know this has probably been covered in other threads, but couldn't find definitive info on the following:

1) What are the pros/cons to running my stock AP1 ECU versus swapping in the '05 ECU? With AP1 ECU I understand the rev limiter will still be 9k so I'd have to manage my shift points to prevent over-rev, but will the motor run sub-optimally?
2) If I want to use the '05 ECU, what exactly needs to be done to enable it?
3) How will the AP1 gear ratios pair with the newer motor - will shifting up at 8200 still keep the motor in VTEC?

Any other input is welcome too. Thanks in advance!

 

Hey Zygrene

Why choose an F22 in particular? Wouldn't getting a replacement F20 make it much easier and literally be PnP?
I'd assume the '05 ECU would be a direct swop with the AP1 F20 ECU since its non DBW. Could be wrong though so other members can chime in on that.
Gear ratios - I'd expect a higher top speed in your case if you go through with this swop and yeah, you may fall out of VTEC every gear since you lose a whole grand in RPM. Best remedy would be to tune it with a lower VTEC engagement point.

BTW, I enjoy your channel! Keep it up

 

My mechanic has an F22 ready to go, and for a solid price. Also since I'm keeping the stock AP1 transmission I imagine the midrange torque of the F22 will help corner exit acceleration at the track.

Can you explain why you think my top speed would increase after the swap? Tuning it with a lower VTEC engagement (4500 maybe?) sounds like a great idea. Do you have any suggestions with '05 ECU?

Thanks! Will definitely do some videos on this topic if it comes to fruition.

 

I see. All good then. Just remember to make sure your exhaust valves aren't too tight as is the case with the F22.

Since the gear ratios are marginally longer than the AP2 trans in theory you should get a higher top speed. Well not just in theory, in practice several guys experienced differences in gear per gear top speeds in AP1 vs 2 scenarios. Check this out: https://www.s2000.com/forums/engine-...ear-ratio.html

Lower VTEC (4500rpm) should be most beneficial in your setup. You would definitely stay in VTEC at nearly all sections of a track except for really low speed bend forcing you below 4500rpm. I have a '00 AP1 bro so no real hands on experience with the '05's I'm afraid.

 

 

Don't mean to pry but, what happened to your OG '00 F20?

 

My '06 has the VTEC engagement lowered to 3600 rpm. No problem staying on the high power cam. I assume your car will require an aftermarket ECU.

-- Chuck

 

 

Just a suggestion. If you end up swapping a motor in, change the bottom end bearings. It's not a hard job. OEM honda specs are stupid tight. Had a buddy that swapped a f22 into his car last month, literally on the SECOND DAY of having his car the oil light came on....the main bearings were toast. I have 3 blocks in my shop right now all of them had the mains starting to go.

 

first of all i love your youtube channel

1 I personally have swapped an 04-05 f22c into my brothers 2001 s2000 and we ran the car with the oem 2001 ap1 ecu. yes the rev limit will still be 9k and no i do not recommend revving it to 9k. With my brothers car we just always shift at about 8k. Motor seem to run fine but once every few months it would throw a lean code. I would recommend just ruining the ap2 ecu or getting a stand alone and getting a custom tune.

2 the s2000 have what they call immobilizer in the keys and the ecu. Your ap1 ecu will only start your engine because it senses the chip in your keys. Your 05 ecu is set to only start the engine when it senses the keys of its original car. if you want to run the ap2 or any stock ecu that is not the origional ecu that came in your car you must take the immobilizer out of the ap2 ecu but by doing this you your car will be easier to steal. Or you can have the ap2 ecu set to your keys which i believe can be done at any honda dealer.

3. The ap2 engine is a faster and more powerful engine so it will be fine with the ap1 transmission. but with 8k shifts and the factory 6k vtec crossover you will not stay in vtec. getting a standalone and a custom tune will solve this issue.

You need to boost your car. I'm tired of watching you get smoked on the track by all the porches/vetts/vipers/mclarens/and everything else