If you want to "feel" a difference and those 2 are your only choices, you will "feel" virtually nothing with the header. You WILL feel a significant difference with the AP2 tranny. You have 4.57s now. With the different 2ndary reduction gear of the AP2 tranny, you will effectively have 4.75 final drive in the first 4 gears. Gear 5 and 6 will be almost the same as what you have now. If you can get the tranny at a good price, this will be your biggest bang. I have 4.44s now and I'm planning on putting in an AP2 tranny in the coming year. With our additional 1000 rpm at the top of the rev band, an AP2 tranny is a great mod. We can take further advantage of the new tranny's gearing while not sacrificing the 9000 rpm redline - PERFECT!

 

Yea your a dumb a**... I have half the mods he does, the VAFC will help him the most. I just have intake, test pipe, and vafc and I picked up 12rwhp at peak hp, fattened up mid range hp and torque, and I picked up 23 rwhp at 8,900 (after peak power). If those arn't gains then I'm sorry.

Oh yea, I would go for the ap2 tranny!

 

What do you think,is the average price range for an AP-2 tranny?
Any other modifications needed,beside swapping tranny?

 

I'm only guessing as far as used is concerned. I haven't checked to see what a brand new one would cost. Probably an arm and a leg and a big toe off the other leg. Used, I'm guessing anywhere from $1000.00 US to $1500.00 or more, depending on the age and mileage on it. You'd have to take off the output flange from your tranny and swap it with the AP2 flange as the bolts are different sizes.

 

Jeez, $1000-1500 for a tranny! I couldn't imagine spending that much for my Civic

 

lol, another one of the "the s2000 is already maxed out" type of guys.

In case you don't know, the original poster actually has some of the best bolt on modifications for this car. I'm willing to bet his midrange is beefed up around 25-30 horsepower, and peak is probably around 220. With the 4.57 gears and ACT clutch too? His car would stay even with a supercharged S2000.

The S2000 isn't "maxed out" and responds just as well to bolt on modifications as most other 4 cylinder naturally aspirated motors. The reason why people believe otherwise is because most of the products out there do little to nothing, or hurt performance. There are, however, many products that do help a lot. It just takes time and research.

I also would go with the 04 tranny. I REALLY REALLY want that J's header, but I cannot justify the price of it. 1200 for a 4 cylinder header? There are premium headers for v6 and v8s that are half that much.

 

people spend $3000 rebuilding their Chevy trannies at Aamco every day

 

As much as I agree with you that his mods are all go and no show , there is no way he can stay with a SC s after 60mph. From 0-60 it will be a very very very small difference, but after that, you better watch that small opening between your butt cheeks, cause someones gonna get raped here

 

For a change I actually have to slightly agree with you here jakub...with those mods he wont be far off from an SC, but it will pull him in third. At 240 or so N/A whp it'll start to be a little closer yet probably through 3rd gear

I say that either mod you get, you'll be happy. But personally I would get the J's header with where you are at right now since you already have 4.57's.

After you get the J's header, you should be pushing some good power...it'll be quick

 

i decided to go with the tranny. hope to pick it up, installed, and ready to go by early next week. i'll post reviews then. xviper, i know the difference from 4.10 to 4.57 is 11.46% but does the 04 tranny throw anything off? if so, how can i calculate my yellowbox setting for my02, 04 tranny, 4.57fd, ap1 rims?