Intake and Exhaust performance effects

[Tuning Spirit]

Hey guys, another stupid question from a stupid guy. I was wondering what the difference in performance effects (throttle response, acceleration, idle and redline differences, etc....) I would come accross from the intallation of an intake, intercooler and piping, or exhaust. Also for each type of modification, how would the diameters for each modification affect the parts characteristics (the part I'm really intrigued by, as there are so many diameters for intake, intercooler and exhaust piping available). I'm a stupidhead when it comes to engine performance, so any help to this extensive question would really make my life better as I can't find anyone who is willing to help, but would rather tell me to buzz off.

 

[TeeWX98GST]

I'm a stupidhead

Lol.

Searching would have probably answered all of your questions. When it comes to the inner diameter of things the general rule is that bigger is better. To an extent. You can overkill this though. Idle and Redline won't be changed by your basic bolt-ons. Throttle response would probably be the only thing you might notice for now until you get to the later stages with tuning. Not sure what else to tell you its pretty basic. You can learn alot with the search button, use that first next time instead of directly asking for people to help you. Also sounds like you need to get down some of the basics first and learn a little more about your car and how it works before you start swapping parts in and out. Just my $0.02

 

[knochgoon24]

Larger exhausts result in less back pressure, which is good for turbo cars. 3" is about as big as most people will ever need. Some people choose to run without a catalytic converter. It's against federal law to drive in the US without one, but some people take their chances. They create some back pressure, but hi-flow are available.

Unless you upgrade your turbo, you really won't need to worry about a bigger intercooler. An intercooler that is too large can cause some lag. Some designs are better than others, but for most people an ebay core works pretty good. For IC piping, anything bigger than 2.5" is excessive for most people. The difference in size really doesn't make a huge difference in lag according to some people's calculations.

Air intakes can increase spool up time by creating a smoother flow into the turbo. Same with aftermarket air filters. The downside to some filters is that you often sacrifice filtering capacity for flow.

None of these modifications will affect your redline. That is set mostly by your valve train. The stock turbo is worthless above the stock redline, so unless you upgrade your turbo, you don't need to worry about new springs and retainers. Cams also affect where your car breaths the most efficiently.

If you stay on this site long enough and read around, you'll learn most of this information in most threads.

 

[jrohner]

Air intakes can increase spool up time by creating a smoother flow into the turbo. Same with aftermarket air filters. The downside to some filters is that you often sacrifice filtering capacity for flow.

None of these modifications will affect your redline. That is set mostly by your valve train. The stock turbo is worthless above the stock redline, so unless you upgrade your turbo, you don't need to worry about new springs and retainers. Cams also affect where your car breaths the most efficiently.

You mean decrease spoolup time (you'll get full boost at a lower RPM). Exhaust has a good effect on spoolup, and especially on how hard the 'hit' feels; I'm not sure if an air intake / filter makes much difference or not.

They pretty much help everywhere in boost and spoolup, but yeah the HP by around 7+ grand will still be NOTHING with the stock turbo.

If you get a 16G and run about as much boost as you can with a good tune, then moving to bigger cams (272's, aka stage 2) helps a reasonable amount, but I can't imagine a worthwhile increase before then.

 

[Tuning Spirit]

Lol.

Searching would have probably answered all of your questions. When it comes to the inner diameter of things the general rule is that bigger is better. To an extent. You can overkill this though. Idle and Redline won't be changed by your basic bolt-ons. Throttle response would probably be the only thing you might notice for now until you get to the later stages with tuning. Not sure what else to tell you its pretty basic. You can learn alot with the search button, use that first next time instead of directly asking for people to help you. Also sounds like you need to get down some of the basics first and learn a little more about your car and how it works before you start swapping parts in and out. Just my $0.02

Thanks for the feedback guys. Oh, and I did use the search button extensively, as it is always my first resource. Even went down to using just single key words like "diameter" and "intake" and "exhaust". I'm the kind of guy who'll hate myself for asking questions as it means I'm depending on others, but that's just me.
Special thanks to knochgoon24, you hit all the right tunes for me with your explainations.