I don't think I saw anyone mention gearing... isn't it shorter on the AP2 causing it to read higher regardless?

 

If anything I would think the Ap2 would have taller gears to account for the loss of 1,000 rpms on the top end.

 

I would say this is part of it. Yes the Ap1 revs up to 9000rpms but look at a dyno sheet i don't think there would be any gains in that high of a band in the S2000. Now yea its a newer engine. But look at old threads when the S2000 first came out. Now look at threads where the Ap2 came out. The AP2 does seem to have better numbers on dynos. But it does matter on dyno and temps out side. But all in all i would say that the AP2 would be a little bit better than the AP1 if not why not just keep the AP1. And a older engine with some millage is not going to really affect the numbers on a dyno. Example so if i had 10k millage and my dyno read 200rwhp. I dyno again this time with 60k millage im sure my numbers would be very close if the temps and on the same dyno. Really at least we all have a S does not matter about numbers it all about how it feels when u drive the car

 

Sorry but the OP is stretching it a bit. Maye 5HP more, but not freaking 20-30.

 

if the AP2 was a significant performance increase over the AP1 Honda might have kept the S2000!

Honda does this with all it's sporty cars! It builds a car that is ahead of it's time just to let it run for too long till it becomes outdated and the competition takes over again.

 

[QUOTE=JLUDE,Sep 18 2009, 11:29 AM] Honda does this with all it's sporty cars!

 

Most of the time I've seen ~200WHP for stock AP1s vs ~210WHP for stock AP2s, right in line with the OP's guess of a 10whp difference. Honda had 4 years of time and a displacement bump of 10%. To pick up 5% more power isn't a stretch. With the redesignation of HP, there would be no sense dynoing an 04 to show 250HP only to drop to 237HP right after when the SAE HP change went into effect.

But I hadn't thought about the tranny--they did change the brass synchros to carbon for higher gears with the AP2 tranny, right? Maybe a slightly lower drivetrain loss produced part of the WHP gain. I had always figured they made it with the extra stroke.

And 10WHP isn't much. AP2s also picked up a few pounds, which makes the tiny power difference even more marginal. In the end, the faster stock S2000, CR included, will be the one with the faster driver. They just aren't that different.

 

don't forget ap2's tend to run more on the lean side as opposed to ap1's which run pretty rich.

 

correct me if im wrong but isnt our engine hand made or hand assembeled? if so then our cars are slightly different from one another and i agree with previous replies about driving skills and this car requires ALOT of that.

 

Depending on what speed you are racing to. Remember that the AP1 with stock tranny can make the 0-60 run with only 1 gear change, 1st to 2nd. A stock AP2 requires 2 gear changes 1st to 2nd and 2nd to 3rd. The cars will have identical times with a great drive. An average drive should be able to squeek out a win with the gear change advantage.

BTW 1-4 on the AP2 are lower 5th is the same and 6th is slightly taller.