Hatchback STI upgrades
 

Hello all,

I have just purchased myself a STI hatch.

Attachment 68780

Now i am looking for a few things and advice. I have gotten some good advice from rob84 which i am most grateful! But i dont want to pester him all the time!

So basically, im after a more grunty noise from the exhaust note which the standard lacks also better breathing from the car. Now im not really after a whole new system and preferablly to keep the cat! Now im new to the turbo scene and im getting so confused with all the jargon and what inch pipe is going to straight swap ect! Now i have been told to change the downpipe, to what?... Is there two cats on an STI and removing one will still pass an MOT? Could anyone link me to some down pipes!

Secondly i would like more from the air intake. I have been looking at the K&N Typhoon but hearing mixed reviews... What have people got and what do people like?

Im not after massive gains as i've heard the standard engine cannot handle much more over 350 without problems in the forseeable future... Maybe a remap later on after i've sorted out the breathing aspect. I also have handling issues i want to fix aswell! The boat like sway in the higher speeds is downright awful imo! Although i did come from a clio200cup go kart!

If anyone could direct me or offer me any parts they have for sale i may be intrested in i would be very grateful!

Regards Sam

Hi Sam,

I have a hatch as well and have modified it. If you are not looking for too much more power then the best thing to do is take out the centre resinator (Not the cat) and also change the backbox to something with a smaller muffler. When I changed my backbox there were not too many available but I found that a Remus sports backbox did make a big difference (I did remove the centre cat as well as the resinator so that alone will make a big difference). If you are changing the air intake then a re-map will be needed but will get you into the low 300's and bring the torque up to which will feel a lot better.

as far as the handling goes - I do agree the back end is a bit loose but don't fall into the trap that I fell into. I changed the rear anti roll bar without really looking into what was needed. I know you are a long way away, but it's worth talking to Simon at Chevron in Stafford. He is a genuis when it comes to chassis setup and mine (even with mismatched roll bars) feels great after he set it up.

Other than that they are a great car to have a lot of fun in so enjoy it !!

Is taking out the resinator a hard job? Really? so if i bought the K&N typhoon i'd need a remap? Ive heard you dont?... Or is it just advised? What about your cosworth panel filter for sale? Is there many gains in this?

Oh really? I'll give him a call!

I will enjoy it! loving it so much!

the resinator is not a hard job really (although I got a proper exhaust fitter to do it as they have a lift / tools etc.). It's basically just unbolting a pipe and refitting a straight one without the resinator peice).

As for a remap... It's not going to blow the engine up if you don't remap it but as with all modifications you will only get the best out of them with a bespoke remap.

I can't say if the Cosworth panel filter gives any gains. The manufacturer claims gains of a few horsepower (I think they quoted 5 or 6 bhp at the time) but I know it's not going to feel any different on it's own (The complete remap will tie everything together more than just the filter).

Could you link me to where you can get a straight pipe with no resinator? I have a friend with a garage who can do it for me!

Yeh i heard its better to remap! very pricey the remap compared to the price of the unit, in two mind whether or not just to stick to a uprated panel filter.

How much do you want for your cosworth panel filter? Does it make more of an induction growl than standard? I know when ive done it to other cars in the past its made a difference when putting your foot down tone wise.

Also the intercooler... how come some say STI and others (like mine) are just plain? are the logo'd STI ones better in any way?

thanks

I don't have a link as I just got the exhaust bay to make up some 2.5" pipe to replace the resinator. I have since moved on to a 3" Miltek exhause but would not be needed for your power level.

You can have the panel filter for £10 posted, but here is a bit of a cheat idea if you just want a bit more noise without a map.

Underneath your airbox there is a white plastic canister. It's basically an extra resinator to deaden the sound. You can take out your airbox and remove this canister (obviously plug up the hole that's left behind). This will give you a bit more noise without spending a penny !! if you still want more then start spending but the better noises come from fully decatting (a remap would be a must if you go down that line).

As far as mapping goes you can go for open source mapping as I have (I use Duncan Graham aka racedynamix) he has done my car a few times and he is a great bloke.

The std intercooler on yours is fine for up to 400bhp really. It is probably the best of the sti intercoolers.

A panel filter change along with the exhaust mods that wayne describes will see you to around the 340-350bhp mark with a remap.

I am based down the road from you in Bournemouth btw ;) :thumb: