RyanSTI

iTrader: (1)

hey guys, im deciding which exhaust to get,

is there any major benifits of getting a 3inch bore rather than a 2.5, eg are the power increases massive in comparision?

also anyone had any experience with cobra exhausts uk, pre made exhausts?

2003 sti,want power with sound but not to much sound lol



if i was answering this id say, dont buy an exhaust if u dont want sound lol

Coffin Dodger

It's not really a case of how much more/less power a 3inch system will give you over 2.5inch more a case of how much power you are ultimately aiming for.

A 2.5inch system will flow well enough for most purposes, only really need 3inch for 400bhp upwards.

As for what system Hayward and Scott are the originators of after market system for Scoobs, they have plenty of stuff to choose from and if they don't have what you want can make it for you for a premium. Top quality / good value (keep an eye out for group buys on here ). Also try Scoobyworld, their Vortex or Ninja systems are well regarded (some of it's made by H&S anyway ).

Revolution make a competitively priced 3inch system if you fancy going that route. The Jap systems are very good but pricey (Blitz, HKS, APS etc. ).

Lots of choice. Never heard of Cobra exhausts though?

scooby L

I'd say you don't "need" a 3" exhaust unless you plan to push the power envelope more than 360bhp

Just by changing the exhaust will not give you any extra "power" (maybe 10-15) but coupled with a good intake and a re-map the power is then released

Hope this makes sence

scooby L

CD beat me to it...

RyanSTI

iTrader: (1)

roger that guys, im 90% sure i'll get the ninja/ab system seems good value. id proberly gonna be looking around the 350 mark after a decent amount of wedge but nothing crazy.

alot of people dont like intakes on here, k&n, injen etc any reason for this? is there not much restriction with that part of the set up?

Coffin Dodger

Depends, the standard induction on the Scoob is really quite good and even with the paper filter will flow enough for nearly 400bhp. Litchfield Imports use the standard induction on the Type 25 and look how powerful that is.

You can change the panel filter to something like Green Cotton / K&N but the performance increase would be negligible.

Again if you are going for really big power then it can start to limit. Then consider an induction kit, usually done in tandem with a front mount intercooler upgrade as you can't use the standard induction with one. The traditional types sit in the engine bay so not much use as they end up drawing in all the hot air present. Needs some careful shielding and ducting to get a good cold air feed. More recently the cold air feed types have become available which sit in the wing, ideally supplemented with some sort of ducted air feed into the wing from the front of the car.

Never fit an induction kit without a remap, the extra airflow screws the calibration / scaling of the air flow sensor (MAF) usually causing the ECU to run the mix too lean. This will cause det and ultimately a big repair bill for an engine rebuild. A good ECU mapper can however sort things out for you allowing the induction kit to be ran safely and provide with the extra horses as part of the overall modification package you have fitted.

R4LLY

iTrader: (1)

Alot of the intakes on the market today act as "hot air" intakes rather than cold air and are not any more efficient in comparison to the standard airbox.

However that said there are some good setups out there that can yield decent gains with the right setup.
The Blitz has had good results both power wise and sound, the fit looks cool as well.





You can pick them up for a decent price too.

Subaru Impreza Newage 2000> Blitz SUS Induction Kit on eBay, also, Performance Tuning Parts, Car Tuning Styling, Cars, Parts Vehicles (end time 15-Aug-08 21:38:52 BST)

Coffin Dodger

Really??!!?

I've heard the filtration on those really wasn't up to much and that you'd almost be better off without any

R4LLY

iTrader: (1)

Tried the Blitz back to back against the "HKS" mushroom and there was a very noticeable increase, the mushroom kept on absorbing water and too much heat and was terrible!

The Blitz and other kits similar like:

www.slowboy-racing.co.uk - Re:GC8 Cold Air feed. -



Have been excellent and the results tested.


Another option would be Gruppe M who also test and can prove the results, however the Price of Gruppe M intakes is

banny sti

iTrader: (68)

The best filter on the market for the impreza is apexi, it has best filtering, flow and is also completely dry.

Banny

Coffin Dodger

Here you go, found it http://www.mkiv.com/techarticles/filters_test/2/

Blitz, HKS, Apexi, and K&N back to back

HKS was the worst, closely followed by the Blitz jobbie.

Suffice to say I wouldn't let either of those filters within a hundred miles of my engine bay as I value my engine.

WaltonWRX

iTrader: (4)

Had a Ninja on my old wrx, sounded lovely so I've brought another one off a member on here for the new type-r

RyanSTI

iTrader: (1)

cool guys! theres always debate over mods, its good. but not when your a subaru noob like me lol !

i used to have an injen on my mazda, used to sit down in the wing, rolling roadedat a 7hp increase, which is crazy for an intake.

RyanSTI

iTrader: (1)

just bought the ninja 2, with afterburner center section. looks nice. just in time for usc phew!