fuzzmuzz

hi just came across a thread with this statement in it and wanted to know if this is true.

You can de-cat the Bug WRX without a re-map as the ECU sorts out fuelling etc and the TD04 doesn't overboost as it is too small.

Makes a bit more noise and spools a little earlier though LOL


Shaun

vicks

iTrader: (1)

i decated mine and ran with it for about 2 month and it was fine.
i did get it remapped in the end as i fitted other stuff and needed to.

fuzzmuzz

thats what i was wondering i will get a remap but it will be a long way down the line due to are second child coming.
Did you notice any difference in the car.

powerwrx

iTrader: (11)

pointless decatting if your not going to remap asap... you will get a deeper exhaust note but thats about it.. as for not having any problems not everyones car is the same so you may experience boost issues, fuel consumption higher, CEL might light up on the dash.. imo ide wait untill you have everything you need/want before fitting it all and remapping at the same time-ish.

i had a bug wrx uk model (215bhp)

then fitted...

full turbo back decat
STi panel filter
walbro fuel pump
NGK 7's spark plugs
EcuTek Remap by JGM

and got 280bhp/278torque... if i went for a bigger turbo and injectors ide have broke the 300bhp mark so its worth waiting and saving for what you really want

fuzzmuzz

the only reason im saying fit now is cause i dont really have any where to store them and dont want to risk them getting damaged i was thinking of just doing up-pipe for now and possibly store the prodrive downpipe at the mother in laws. not to fussed about gains till the remap just storage issues.

powerwrx

iTrader: (11)

your choice mate ive given you my opinion.. if you can store the downpipe im sure you can store a foot long uppipe aswell.

fuzzmuzz

and i take your opinion on board mate as im here to learn thats why i asked if that statement i read was true as i have only ever owned mr2 turbos and you could decat them fully with no problems at all and get good gains. I alao heard its a good idea to change the uppipe anyway for one thats one piece to lesson the risk of the cat and sensor breaking up and entering the turbo.
And you dont know my mother in law dont ill even be able to store the down pipe ans my other half doesnt allow any parts in the house due to son.

powerwrx

iTrader: (11)

do as you will then matey... imprezas arnt mr2 turbos though so bare that in mind

fuzzmuzz

maybe someone else can give me some answers seeing as i have two different ones here and maybe someone can answer my question about the up pipe beaking up seeing as powerwrx just likes stating the obvious.

Emmaroids

iTrader: (2)

NO..................

fuzzmuzz

no what.

fuzzmuzz

1what about the question about the up pipe is it safer to replace it with a sti one.

tubbytommy

iTrader: (20)

only idiots fit mods without a remap.
firstly you likely to do damage to your engine and secondly you may lose power and gain lag etc due to lack of remap.
you need to go for a drive in mapped car and see how much better they drive.

powerwrx

iTrader: (11)

stating the obvious... mate, if you ask for advice i suggest you take the advice given, your new to the forum so i would wind your neck in, you have said yourself that you have come from MR2's and obviously dont know about imprezas or you wouldnt need any advice... do it mate, put it all on and dont get it set up for the modifications then in a few months time when you post a 'somethings wrong' thread ill keep my mouth shut.

crack on!

tubbytommy

iTrader: (20)

what he says.....

fuzzmuzz

tubbytommy thanks for the reply i know mapping it would make a massive differnce and i think your right i do need to see the difference. Like i said im still learning about the ecu set up on the imprezas they seem a lot more fragile to other jap cars ive owned. I was just trying to confirm the statement above that was posted on here was true or not im getting alot of differnet opinions. I took the car to xtreme scoobies in boreham essex and even he said that you could decat it without a problem he said bugeyes are ok with it but then im hearing you cant and shouldnt.

tubbytommy

iTrader: (20)

your running the risk of an engine failure also your unlikely to see any gains from a decat if the car is not mapped for it so its pointless.

fuzzmuzz

tubbytommy thanks one more question the guy i bought the car from has uprated the fuel pump and done the 3rd cat delete with a blitz nur spec r system and put a green panel filter in but he never had it mapped will the car still be safe to use with these mobs then staarting to feel a little nervous now about using it.

tubbytommy

iTrader: (20)

i would ring a mapper and ask for some advice, a decat usually requires a remap. panel filter should be ok and so should an exhaust if its the same bore as the original. not sure on fuel pump tbh

powerwrx

iTrader: (11)

car will be fine with those mods aslong as the downpipe cat is still in place... but i tend to keep my truthfull info to myself

fuzzmuzz

ok thanks for the help maybe someone will advise me on here if not ill call someone on monday

powerwrx

iTrader: (11)

someone has just advised you...ME!

ahh f*ck it!

fuzzmuzz

yeah i know sorry posted my reply same time you posted yours geeeez

Midlife......

iTrader: (2)

That's me in the OP.......... it's the STi that throws boost spikes if you de-cat it.

As I said you don't get any benefit in terms of BHP increase or torque as the ECU simply compensates.......

Shaun

fuzzmuzz

Thanks for replying Shaun like i said i know you get good gains from a remap. The wife has been moaning about the parts in the house so when i saw your post i thought i could be ok to get under the car and fit them till i remap in the summer just to get them out of the way.
so your saying the ecu compensates will it do any harm to the car thou or will it just drive normally but alot louder.

vicks

iTrader: (1)

i fitted
decat up pipe
decat turbo back with vortex centre section and vortex afterburner back box
walbro fuel pump
sti top mount intercooler
k&n induction

ran the car for 2 month untill duncan could come up to remap it
it ran ok but did experience fuel cut twice when i got to carried away with the revs so i only drove it steady and not really using the turbo or going above 4k revs as i didnt want to damage anything.

totally different car after remap, well worth the money for duncan to work his magic.

good luck

tubbytommy

iTrader: (20)

+1 he mapped mine monday best mod you will buy

Midlife......

iTrader: (2)

Replying to the OP, we all decatted our bug WRX's BITD and there will be lots of threads on SN going back 10 years.......lots of posts by John Banks

Your main problem will be the CEL's........P0420 from removing the downpipe cat and the EGT CEL from the up-pipe pre-cat removal.

Scoobysport sold an electronic CEL fix as did "Trouser" from TSL Motorsport.

Then you get into Tek 1, Tek 2 and Tek 3 remaps......

All in all best to de-cat and remap together

Shaun