The following information was taken from Nexus Motor Sports, A pro Shop that is very dedicated to our cause. You can visit their website at

www.nexusmotorsports.com

"We recognize that everyone has different tastes and preferences, so the following

staged upgrades were designed with that in mind. This is only a general guideline.

Some components may be substituted or left off depending on personal preference and

racing interest."

The first thing you want to do before adding more power is to go to a reputable shop

that can give you a complete tune-up. Install a set of Magnecor KV85 8.5mm plug

wires and a nice set of NGK plugs. Also make sure that your stock fuel injectors are

cleaned and balanced. If your car is approaching 60K miles, please have your timing

belt replaced if you haven't already done so. With these done, you are now on your

way to making more power, safely!

What we want to do here is to improve the flow of air through the engine. The stock

airbox is very restrictive. Replacing that with a open element intake like the K&N or

HKS Power Flow helps the engine breath better by allowing more air in to the engine.

Likewise the exhaust. The stock exhaust from Mitsubishi uses small piping that are

bent in a lot of places, restricting flow. We recommend going with a larger diameter

and mandrel bent exhaust such as the Greddy unit.

Once we have opened up the air flow with the intake and exhaust, it is now time to

turn up the boost! By installing a boost controller, we can take advantage of what we

did in stages 1 and 2. This also allows us to put the factory turbo to full use. The stock

boost on the '91-'93 cars were set at around 9 psi, and the '94 and newer cars are

factory set at 12 psi. With the boost controller, we can now safely turn the boost up to

14 psi. At this time, it is extremely important to install a aftermarket boost gauge. The

stock gauge is highly inaccurate! The boost gauge is both a safety precaution and a

great diagnostic tool. This allows you to make sure that your car is not over-boosting or

under-boosting.

After we turn up the boost, it is now time to free up the exhaust some more. The

downpipes that comes from the factory is (what else?) very restrictive, not to mention

heavy. By installing an aftermarket downpipe, you will notice a gain of 15 horsepower

and a weight savings of approximately 10 pounds. Installing a street-legal high flow cat

is the next step. A high flow cat will further increase horsepower by another 5-10 HP.

Horsepower output after stage 4 is at 400 HP.

The stock Y-pipe (the plastic pipe that goes from the intake to the throttle body....in

the shape of a "Y") has a tendency to blow off at high boost. This usually happens

around the 15 psi and up mark. What you will notice is a loud pop and something

hitting the hood from below. The car will stall out and you will lose all power functions

(including power steering). Don't worry! More often than not, all you need to do is to

re-attach the Y-pipe, just make sure to have a screwdriver handy. By replacing this

plastic "Y-Pipe" with a aftermarket one, you will eliminate the chances of the pipe

blowing off as well as allow more air to flow through. Another mod to do at this time is

a blow off valve upgrade. A blow off valve protects the turbocharger from compressor

surge (boost pressure being forced back to the turbo when the throttle plate is closed

under boost). What you will notice with the installation of a BOV is quicker boost

response and recovery. You won't really see a horsepower gain, what you will notice is

that the turbo is aggressively spooled up and ready to go at a moments notice (which

leads to the feeling of more power).

At this time we will take a break from adding power and focus on reducing weight.

This is especially critical when your car weighs 3,800 pounds! The stock 91-93 17"

wheel and tire combination weighs 52 pounds. By going with a lighter wheel, you will

reduce the critical upsprung weight. This aids in all facets of the car from acceleration

to braking to handling. Some wheels like the BBS, Blitz, and SSR wheels weigh less

than 20 lbs. each, allowing a potential savings of 15 or more lbs. for each wheel and

tire. Stay away from chrome! You know the old saying: "chrome don't get ya home"!

After upping the horsepower beyond the 400 HP mark, you will begin to notice the

shortcomings of the factory clutch. At this point we suggest a upgraded clutch that was

designed to handle more power as well as provide a smooth engagement.

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