people on the forums have been saying that intakes don't do much and IMO, they do - and quite noticeable in fact.

for example, how could a factory intake w/ THREE parts be more efficient than an AEM v2? the AEM weighs less and is less restrictive. period.

also, for exhausts, people say that "you lose low end torque and power" (which we D17s desperately need) with an aftermarket exhaust with larger tubing. if this is indeed the case, why not just get a new less restrictive muffler/axle back and keep the factory size? like a HKS hi power axleback? that ways, you won't loose the low end tq but you'll open up your exhaust slightly. btw, mufflers upgrades alone sound great (as long as its not a cheap no name ebay one).

opinions?

 

yes aftermarket intakes are better than stock, but arnt worth going mad crazy over. aftermarket exhaust will cause u to lose a lil bit of low end power. even way more so if u get piping larger than 2.5" if ur still n/a. ppl say i/h/e are all pointless because with that u only get a few extra whp and ur almost halfway there to a decent turbo kit with the money u spent on i/h/e. which u could easily get 50+whp.

 

Don’t see how number of parts or weight affect efficiency of intake. And yes, it is better than any aftermarket, if you factor in all complex of things, not only high rpm performance on full throttle.

The reason for this is that a car engine is an extremely complex device, built on millions of compromises, even if you do not realize this. There is much more to intake and exhaust than just how much restrictive they are. Automakers spend literally billions of dollars to design balanced cars, and no aftermarket firm can compete with them on this field. Those firms just satisfy your demand for high rpm performance on full throttle as much as their R&D budget allows, and sacrifice everything else to achieve this.

If you are really interested in this, try to read some books on how engine works

 

is my logic in any way corect about the axle backs though?

 

Well, an axle-back addition is really more for the sound. Is it less restrictive? A little. Maybe to the tune of one,
or maybe even two, whp.
A full exhaust will net you only 4-6 whp in total. A good stainless exhaust will smooth out the air flow just
because of the material it's constructed from, and a good, quality exhaust will be even better. Until you are making
over 200whp anything bigger than say, 2.5" is useless.
And don't forget, you have to look at the bigger picture. Intake+header+exhaust=bigger gain than the sum of it's
individual gains.