Ap1 vs Ap2 for track use and eventually time trials
 

I know this topic has been covered a million times, but I could not find the answer to my specific question. Either the posts that I found were way too old and is not valid today or they talked about street use. So with that said, I'm planning on getting a s2000 to use mainly as a track car and maybe take it out on weekends on nice day, but very rarely. Currently due to budget constraints I won't be able to start competing in time trials, however eventually I want to set the car up to compete in TT5 or TT4 whichever the car would fit in. So I'm trying to decide between Ap1 and Ap2. Now from the past articles the general recommendation was Ap1 due to lower initial cost but as I look more into the cars it seems Ap1 and Ap2 prices have converged and 2001-2003 and 2004-2006 cars are very similarly priced. So my question is for track use which year cars would be better? I'll be driving the car to and from the track if reliability is an issue, but from what I have found both Ap1 and Ap2 seem to be equally reliable.

AP2 for power reasons. The other local guys are in AP2s and have been dynoing about 20whp more than I am with similar mods.

AP2 is easily faster. Set the car up for TT5 if you want to be nationally competitive.

I would say an 06+. Once drive by wire came out, it allowed flashing of the ecu without a full replacement or piggyback. Also, for reasons that become more important in a race car, it gives you can-bus. This is important, because you can get datalogging equipment with a cheap bluetooth connector. My 05' gives data at about 1hz which is worthless. I prefer the torque of the AP2 and I think it overall is the more composed car. All of them are great choices for various reasons. You can't really go wrong with any S2000, but in my opinion the first two reasons listed are the big reasons I wish I had gotten a newer one.

Did you happen measure your respective cars in stock form first? Were you using the same dynamometer for your tests? While some early AP2 reviews indicated the 2.2L engine was producing more horsepower than what Honda was claiming based on their dyno tests, it was less than a 10whp difference compared to the 2.0L engine in the AP1. I would imagine that, along with variations from one dynamometer to the next, could account for such a difference if the more optimistic dyno was used to measure the AP2 cars.

I'll just add that not only is AP2 more powerful, it also has better suspension geometry, and it's more reliable—especially if you mis-shift. If you did get an AP1 you'd want to swap to AP2 valve retainers (which brings the cost even closer), but even so you've got less headroom in the case of a small mechanical overrev. (There's also room to raise the redline on the AP2 if you want.)

I did on mine. Car is an 02 but I swapped to a F22 when that motor went. Peak went up about 13WHP, but the main gains were in the midrange where it was ~20whp better than my F20.

A 2006+ would be best since you can flash tune it and gain a lot of mid-range and a bit more overall power.
Pre-06 cars will need some kind of ECU and tune which K-Pro would be one of the better options but it's expensive. It's just more affordable to start with the better car.

And I'm going to use this excuse to my grave as to why I'm off your times. F20 vs F22 is unfair. :LOL:

For those running an AP1 already (or if the OP ends up in an AP1 for whatever reason), the Karcepts Emanage with AP1 tune is a nice thing to have. You want the high flow cat and preferably a header with it to avoid a dip in power around 4000 rpm. While tailored for autox, it is great across the board. The AP2 still has more low/midrange grunt but it at least closes the gap some.

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