Yet another decat question
 

Im wanting more noise from the scoob now im thinking decat ?
But both front and centre
Or just centre

I already have a proR £600 rear can but not much differance

Also would it need to be mapped after the decat as ive read some people say yet others say only if front is done

Cheers chaps

Might help if you say what car you have

Any air or fuel related mods require mapping, unless you like boost spikes, lean running and det. £600 for a backbox is obsurd, a Blitz nurspec cat back system is less than that new.

Sorry my mistake got a 09 hatch mate
Back box was bought by previous owner have recipts for all stuff on car the rear can was 575 to be exact made by proR appently made by scorpion so it needs a remap on any decat

Yes a remap will be needed to get the best gains and also make sure everything is in check. The price of a remap is nothing compared to a rebuild and least you will have confidence every time you have a spirited drive that the car is running safe. Stick with a quality exhaust system and top mapper and you wont go far wrong :thumb:

So any decat at all needs a remap

yup, you've said that twice now so it must be sinking in. Alternatively, join sioc and run a bailey dump valve, induction kit and decats until the engine ****s itself and post up videos asking "whats this noise".

I was just making sure as ive seen posts that say only downpipe needs a remap

1st thing you need to learn is that its pointless bolting stuff on an impreza if you're not going to then get a map to feel the benefit.

I have only ever seen 1 impreza make more power from unmapped mods and that was a uk2000 that had a 255 fuel pump and decat exhaust and the owner fitted an SP Prodrive ecu. It made 248bhp and the air/fuel/knock etc were all ok.

Heres some basics regarding unmapped mods.

Decats - increase airflow, cause lean running, det and boost spiking if unmapped
Induction kits - increase airflow, commonly cause maf issues due to their fragile construction and location
Front mount intercooler - cooler charge temperatures, can be laggy if unmapped
Non Recirc Dump valves - no benefit, chavvy noise, can cause boost leaks, stalling etc
Ebay shiney headers - welds tend to be poor quality, up pipe diameter is usually too large so affects spool, fitment is often poor.

Hatches have ecutek racerom as a mapping option which has some nice features, so do your research and modify wisely.

Thanks mate will do