Originally Posted by tbohar

This thread will be long, and very informative. If you post "How do I make my civic fast" without reading this your thread will most likely be deleted. If you want to make your car fast, and reliable, the first step is to read this thread word for word. You have to know: How much it's going to cost, how much power your going to gain for your money, if it's worth it at all, and which route your going to take (Turbo, Nitrous, Engine Swap). Simply put, if you don't have the patience to read this, you don't have the patience to make your four cylinder civic fast.

Let's start with some basic information on the "D" series engine. This engine does not gain any power from bolt on modifications NONE, and lacks the aftermarket support that other Honda engines have (K and H series, for example). A turbo is the only real way to make a D series fast, this is both expensive and needs to be done properly to work right. Nitrous could work but it's risky business and again needs to be done right. If your a noob and have found this before posting "How do I make my civic fast". Congratulations, your already one step ahead. If you really want to keep your "D" series engine and want to make it fast, expect to spend at least 4000 dollars to make it fast and reliable. Your other option is an engine swap. There are laws and regulations on engine swaps depending on your cars age and the age of the engine. It's illegal to install an older engine into a newer car (For Example: You can't put a B18 in a 2005 civic because the engine is older than the car itself, it's against the law) If you still feel the need to make your "D" series engine fast, read on:

I can't even begin to stress the importance of KPRO ECU. It is expensive, 1000+ dollars. Any successfull turbo setup or even engine swap requires KPRO. If your not willing to spend the money on an ECU upgrade, don't bother spending your money on other things. There are other ECU upgrades, but KPRO is by far the best, don't waste your money on others just to buy a KPRO later.

Originally Posted by xRiCeBoYx

Basic performance "gains":
Almost everyone will start by adding an intake, header, or exhaust to their car to increase performance. Although you might "feel" and increase in power, those gains will be minimal, especially on a D-series engine, like most of us have in our cars.

A common misconception is that adding an intake, header, catback, and high-flow catalytic converters will increase horsepower. The reality of these "performance parts" is that adding these things will not "increase" anything. The only thing it helps "increase" is the flow of air through parts that are originally restricted by OEM parts. With these factory restrictions out of the way, your engine will have to "work less" for the air it needs to operate, effectively increasing your engine's performance

-But, they said I can get 10WHP from putting their intake on my car!
-No. Maybe on a k-series. And even then, 10whp is a bit overzealous. If you look at Import Tuner power pages, you'll see the gains usually around -3 to 4 whp gains (yes, that first number is negative). Most times, especially with a D-series engine, you'll get no more than extra sound from the engine bay. I'm not saying that it's a lost cause adding an intake to your car, because it will allow your engine to breathe easier. That can set you up for real performance gains in the future. For now, you can eBay pipe it with a QUALITY filter, like an AEM Dryflow. Gearbox has a thread out there in the sea of threads about how K&N filters, although they flow well, suck for filtration, and are worse than stock for filtration. You can also go the spendy route if you so please and get some fancy schmancy intake. I can't knock on that route becuse I'm (xRiCeBoYx) rocking an AEM V2 intake.

-Alright, I get the point of the intake. What about the exhaust? The faster I can let the exhaust out, the more performance, right?
-Again, no. Stop that. Your car requires SOME backpressure to work. If you don't believe me, disconnect your downpipe and try and drive around. You'll notice some MAD losses at the bottom end. I (xRiCeBoYx) know this from experience when I installed my first Random Technology High Flow Cat and misaligned the downpipe and header by just a half inch. My car sounded like a harley-davidson and I could barely make it up a driveway without almost killing the engine. If you're running boost, then that's a different story, but we'll get to that later. For a naturally aspirated car, not built engine, a 2.5" exhaust would be the most you'd need, and even that's pushing it. Also, if you wanna get an aftermarket header with runners of a larger inner diameter and pair that up with a cat-back, then you're also doing effectively nothing. The downpipe would still be the limiting factor, and the exhaust gases would bottleneck at the downpipe, leaving you with that flow restriction.

-Doing your homework on a proper intake/full exhaust setup, which can end up being pricey for the minimal gains, can not only give you a little something, but can set you up better gains with any future mods that will create power. Also, if you do your homework right, you won't sound like a ricer, but your exhaust tone will make people say "wtf..? that's not how a rice rocket's supposed to sound.." I've gotten that reaction from many of my friends before. (intake: AEM V2, exhaust: Kamikaze ceramic coated header, random technology high flow cat [2.25" downpipe], A'PEXi WS-II 60mm [2.36"] cat-back exhaust)

Rotational Mass..?
-Alright, I didn't know what to call it, so that seemed like a good lead in. Some of the losses you'll get from the crank to the wheels is any sort of rotational mass. Physics says that the heavier a circular object is, then more work is involved to rotate it. Now, what ever could I be talking about? A couple of things, actually. For you guys blessed with manual transmissions, a lightweight flywheel would "free up" some of those lost ponies. The stock flywheel in a D17A2 is something like 17.x pounds. ACT makes 2 lightweight flywheels, one at about 11lbs and another at about 8. Exedy also makes one at about 8 lbs. With a lighter flywheel, the less weight your putting on the crankshaft to rotate, and thus less rotational mass losses at the transmission. You'll not only see your revs come up faster, but they'll drop faster, too, again, due to the less weight on the crank coupled with a thing called inertia. That will give you a "smaller window" to engage the clutch, so it'll get a little getting used to.

-Another place where rotational mass will come into effect is your rims. A lot of people like to upsize their rims because they look better. However, with a bigger rim often comes more weight. There are plenty of rims out there that are light weight and will help with performance a bit. Some of the more affordable brands you'll find with lightweight rims are konig and buddy club. www.wheelweights.net has a nice list of rims with weights. You won't see every rim on there, but it gives you an idea of how much heavier some 17's are than stock 15" steelies.

Originally Posted by bomerman19

about 20 to 25 extra hp at the wheels with the stage 1 and it works well with bolt ons

stage 2 needs springs and retainers and crower doesn't mention it but I will tell from having more experience than anyone else with that cam you need k-pro in order to get the car to idle with stage 2 and k-pro is not cheap

but stage 1 awesome!!!

Originally Posted by Truenoxxx

really good stuff right here. i might be getting out of the subject but when it comes to saving gas? would the replacement of fuel pump do it?