Celica Forums Install Guides and Technical Articles Engine and Transmission Guides [ENGINE] Performance, What Should I Do First?

Guide to the Aftermarket Performance, What Should I Do First?
By Brabus151, 2002

Step 1. Intake
This must be one of the most common and easiest upgrades. There is a huge market for filters and intakes. The intake does not really add any horsepower it just quits restricting the engine from freely breathing. Intakes are available in two versions. CAI(cold air intake) and normal under hood mounted intake. The most common intakes are Iceman and AEM. Both have there advantages. The AEM is made of metal which means that it heats slower but also cools slower but I think that the metal looks better. The Iceman is made of plastic and some people say that it will melt. The Iceman can be changed at will from CAI to under hood intake. The plastic heats faster but also cools faster. It's your car and your decision.

HP Gain: 3-6 (depends on temperature and type of filter you are running)
Companies: AEM, Iceman, Injen, HKS, Greddy, K&N, Apexi.


Step 2. Exhaust
This has got to be one of the biggest and most competitive aftermarket products. Anyone who is Anyone makes an exhaust. This is also an extremely easy bolt on option. There are pretty much four possible upgrades here. I will start with headers. These come in two options. 4-2-1 and 4 into 1. I am not sure how they differ but I have heard that the 4-2-1 headers give the most torque. next there is the muffler. That just depends on what you are going for. Looks or Loudness. The cat converter is usually the next upgrade. I think it is best to buy an aftermarket one because I have heard that you can actually get more power like that rather than just taking it off. Not to mention the huge ticket you can get from taking it off. And the last option is to just replace the whole pipe and make the diameter larger. You can buy hundreds of different variations of this but all pretty much do the same thing. Make your car a little faster and a lot louder. Apexi World Sport is a good option for a quieter exhaust.

HP Gain(Muffler): 1-5
HP Gain(Headers): 1-5
HP Gain(Pipeing): 1-3
Companies: HKS, Greddy, Apexi, Bosal, Tanabe, DC Sports.


Step 3. Suspension
Some people overlook the suspension of a car and just think of it as a way to lower the car. Suspension is just as important as almost any other performance feature. Ask any car racing team I dont care if it is NASCAR or BTCC or NHRA any team will tell you that the suspension is one of the most important things on the car performance-wise. Bad weight transfer can result in loss after loss. OK, so now you know that you need to chunk the stock suspension what are you gonna replace it with? well there are tons of aftermarket suspension components that can be purchased. I do not want to be bias for a company so I will leave it up to you on who's suspension to purchase. And before you slam your car to the ground always think about where you will need to be driving. The lowest I would go would be about 2" off the ground but I got a speed-bump on the entrance to my neighborhood so 2" is out of the question.

HP Gain: N/A
Companies: Koni, Skunk2, Eibach, Neuspeed, Tokico, KYB, Suspension Techniques, JIC Magic, HKS, Greddy.


Step 4. Pullies, Sprockets, and Cams
These options are good for quick acceleration and deceleration. They all offer good Hp gains. The cams allow for real high revving if you buy spoon sports cams your screaming Honda can reach 9k. The type R's reach about 8.4k. The sprockets allow for retard and advance in the timings and need a dyno to be tuned but the outcome can be very pleasing. And the ultra light pullies allow for better acceleration and more HP.These mods take a little more skill and confusion but I would suggest doing all of these mods.

HP Gain: 7-20
Companies: AEM, Unorthodox, Greddy, Vortech, Apexi.


Step 5. Bottom End Build Up
This consist of Boring out the cylinders and buying new pistons and piston rod's. You can buy all kinds of pistons like dome pistons that offer more compression and concave pistons that lower compression. If you are going to run higher compression I would suggest not buying a Turbo or a nitrous system. Sometimes bigger pistons do not mean more power but can actually lower power.

HP Gain: 0-5
Companies: Usually done in a garage.


Step 6. Electronics
If you want my suggestion then there are only two companies that I would buy from for this mod, Field and Apexi. Field has been making VTEC and fuel controllers for a while and I would really trust them. I am not sure but someone told me that there manual was in Japanese. If so I hope you have a lot of rice boy friends. On the other hand you can buy Apexi's v-tec and fuel controller.
Apexi has a very good controller also, very reliable, and accurate if you set it up right.

HP Gain: 0-15
Companies: Apexi, Field, Blitz, Greddy.


Step 7. Super or Turbocharger
If you are serious about making your car fast boost is the next option. Jackson Racing is making a supercharger for the Accord, which is available now and is pretty reliable. The turbo can be annoying because you have to wait for the power to come as the turbo spools up. The large the turbo the more lag. Thus being the reason for twin turbos which over come this problem to an extent by using turbos where one is large and the other is small and variations on that concept. The supercharger is belt driven compression so it always has power from the start. The turbo's do offer a huge possible gain but superchargers are a good alternative boost option. This way you dont have to wait til your turbo spools up and when it finally does the car switches gears. Before you make this mod you really need to do steps 1-6 first because otherwise you will run into a lot of problems.

Hp Gain: 50-200+
Companies: Garrett, Greddy, HKS, Blitz, Turbonetics, Rev Hard, Star Performance.


Step 8. Brakes
Now you got you little pocket rocket rolling you need to stop all of that power. There are three basic things you need to do when preforming this mod. You need Bigger Brake Rotors, (drilled and slotted rotors from AEM) New and better Calipers and Brake Pads (you can also buy these from AEM)

HP Gains: N/A
Companies: Brembo, AEM, Baer, Power Slot, Wilwood.


Step 9. Nitrous
The all known power of N20 its not NOS, that is a company. The movie the Fast and The Furious made NOS so popular but here is the truth to how it works and why it does.

When you heat nitrous oxide to about 570 degrees F, it splits into oxygen and nitrogen. The injection of nitrous oxide into an engine therefore means that more oxygen is available during combustion. Because you have more oxygen you can also inject more fuel, and that means the same engine can produce more power. This added 02 can let the engine burn a lot more fuel thus increasing power. Nitrous oxide is one of the simplest ways to provide a significant horsepower boost to any gasoline engine.

Nitrous oxide has another effect that improves performance even more. When it vaporizes, nitrous oxide provides a significant cooling effect on the intake air. When you reduce the intake air temperature you increase the air's density, and this provides even more oxygen inside the cylinder.

A property of nitrous oxide is that at about 565 degrees F., it breaks down into nitrogen and oxygen. When it is introduced into the intake tract of an internal combustion engine, it is sucked into the combustion chamber and, on the compression stroke, when the charge air temperature reaches 565 deg., a very oxygen-rich mixture results. If we add extra fuel during nitrous oxide injection, the effect is like a super charger or increasing the compression ratio of the engine.

Automotive nitrous systems work like the automotive equivalent of a jet's "afterburner" and is used for short duration extra bursts of power.
Nitrous oxide has this effect because it has a higher percentage of oxygen content than does the air in the atmosphere. Nitrous has 36% oxygen by weight and the atmosphere has 23%. Additionally, nitrous oxide is 50% more dense than air at the same pressure. Thus, a cubic foot of nitrous oxide contains 2.3 times as much oxygen as a cubic foot of air. Just do a bit of math in your head and you can see if we substitute some nitrous oxide for some of the air going into an engine than add the appropriate amount of additional fuel, the engine is going to put out more power.

Simply stated, nitrous oxide injection is very much like a supercharger or a compression ratio increase in that, during combustion, it can dramatically increase the dynamic cylinder pressure in the engine.

The problem with nitrous oxide is that it is fairly bulky and the engine needs a lot of it. Like any gas it takes up a fair amount of space even when compressed into a liquid. A 5-liter engine running at 4,000 RPM consumes about 10,000 liters of air every minute (compared to about 0.2 liters of gasoline), so it would take a tremendous amount of nitrous oxide to run a car continuously. Therefore a car normally carries only a few minutes of nitrous oxide and the driver uses it very selectively by pushing a button. Small doses of nitrous oxide can be used in stock engines to gain 25-35% more power. In my opinion, any more than nitrous than that with a stock engine compromises durability too much. This is not only true of nitrous but any modification. Take a stock 82 or 84 engine, up the horsepower to 300hp and do nothing to improve durability and your engine will eventually suffer. Once you pass the 35% power increase mark with nitrous oxide you need to look at things like forged pistons, better connecting rods, better bearings, etc.

HP Gains: 50-400+ (dependent on many variables)
Companies: NOS, Nitrous Express (NX), Venom, Zex.