Motion-Mx

iTrader: (2)

Hey,

I had my magnex de cat fitted today by ExhaustsUK,and I hear a slight whistle when coming on boost,and when coming off the gas,is this normal? a guy I know with the same de cat said it's probably just turbo noise you can now hear where as you couldn't with the cat's on.

I was charged 3 hours labour by the way!

Thanks,Ben

powerwrx

iTrader: (11)

yep, just the turbo whistling mate...great isnt it

Motion-Mx

iTrader: (2)

phew,

haha well it didn't sound great on the way home,because I was thinking I had an air leak haha,but I'm sure i'll come to enjoy it now.

Thanks,

ALi-B

iTrader: (1)

If its the downpipe cat thats been removed, then yes you will hear the turbo whistling more.

Labour maybe a bit on the high side, but its not a simple swap (intercooler off, heatshields, LOTS of rusted nuts and bolts than can and do shear off), so if its the original downpipe and its well rusted then that will incurr extra labour to remove it.

I know when I did mine the first time round I sheared two bolts on the turbo and most of the bolts on the heat shields.

Roger.m.

mine whistles mate i thought my dv was leaking but its the turbo it sounds good.

Glowplug

iTrader: (8)

yeah, as above, perfectly normal

3 hours ain't bad, they can be a biatch to get off

Motion-Mx

iTrader: (2)

Hey,

ok I'v just been for a run in it,and every now and then when just coming on boost the car judders slightly and the turbo makes a chatter type noise,the car is standard apart from this decat and a green group N panel filter. is this because the fueling is now way out? is the car safe to drive?

Thanks,Ben

Motion-Mx

iTrader: (2)

anotehr thing i'v noticed with my car,before I even had the de cat fitted,is sometimes the car pulls really strong,and other times it seems really under powerd? I'm hoping this is common in standard impreza's,I'm pretty sure it's not all in my head as eve the misses has made the same comment.

Ben

bluenose172

iTrader: (2)

Ideally you need to get the car remapped after fitting a decat.

r1c

iTrader: (9)

What model is it? Be progressive on the throttle it should 'pull' all the time then

Glowplug

iTrader: (8)

Could be down to a bit heat-soak mate. What MY is the car Ben??

Motion-Mx

iTrader: (2)

it's a 03 STi, is it a common sort of thing then?

thanks

Roger.m.

reset the ecu ! instructions on jolly green monster website.

Glowplug

iTrader: (8)

Yeah heat-soak is a common prob, ie, if you have been giving it some beans say on a motorway then come into town/traffic and try and go again it will feel a little under power

Motion-Mx

iTrader: (2)

will resetting the ECU really help? thanks i guess i'll have to live with this heat soak then.

Roger.m.

usually only get heat soak if an induction kit has been fitted. mines decatted and whistles hasnt been remapped but i connected my induction kit to the exsisting pipe that comes out of inner wing with some aluminium ducting. goes like a rocket.

Turbotits

iTrader: (2)

Sorry to be rude thats rubbish. the top mount intercooler will suffer heat soak regardless of induction kit or not

to get the best from the de-cat a remap is required. It may be boost spiking which is what the judder could be

It at the least should be checked properly for afr's,det etc

And more whistle is normal

Roger.m.

the top mount is directly under the bonnet scoop. hot air from around the engine is drawn in through the induction kit.

Turbotits

iTrader: (2)

you obviously dont understand heat soak. Yes an under bonnet induction kit will take in warmer air if its not sheilded or doesnt have a cold air feed. but regardless of induction kit all this air is drawn through the turbo which heats it. its then past though the inter cooler which cools it prior to throttle body. If there is no air passing the inter cooler via the scoob because maybe your sitting in traffic the cooler doesnt cool the air. This is heat soak and has nothing to do with induction kit. The ecu will pull timing if this happens to reduce det this in turn reduces power.

Glowplug

iTrader: (8)

Well explained Tt

maydew

iTrader: (9)

does this happen when ie in 3rd foot too the floor just about hit 1bar lift off then foot straight to the floor and hit max boost..... if so pretty 99% sure its a emissions feature within the ecu that even ecutek cannot switch off.

ideally newage sti NEEDS to be mapped

seddomyster

iTrader: (9)

does the maf analyse the air passing through the air filter to whether its cold or not an tell ecu to adjust timing to compensate to run right. i sound stupid asking this as dont know much about this part but is it worth putting a cold air feed to air filter to keep air colder plus push away any hot air when driving. its only on a stop the air will afect running or even on a cruise?

Turbotits

iTrader: (2)

>

The maf does measure intake temp yep, But im not sure what action the ecu takes with regard to it.

Yep its worth having a cold air feed too as any reduction in temp will have an effect> but will only be minimal at the maf as the intercooler does the main cooling after the air has been heated by the turbo

seddomyster

iTrader: (9)

i understand mate. i would like to know more about the maf because the colder the air the maf measures its bound to change something with the system i suppose. intercooler cools the air but if that air is colder going through induction by time it cycles through intercooler its going to be that bit colder so more power how i see it. all benefits. cheers for advice. i think ive just basically repeated u readin this lol

seddomyster

iTrader: (9)

also i keep seeing these charge coolers for sale now an then cooled by water system. are these any good

Motion-Mx

iTrader: (2)

Hi,

Yeah I plan on an EcuTek re map soon,untill then I will drive the car steady,the car stinks of fuel now if you stand at the rear,I presume it's now over fueling with the free flowing exhaust?

is it worth re-setting the ecu? what should this do in theory?

Thanks for your help,Ben

Motion-Mx

iTrader: (2)

will disconnecting the battery for 10 mins re-set the ECU?

seddomyster

iTrader: (9)

meant to be 24 hrs i think mate. u can plug the conections under the dash an reset that way

Glowplug

iTrader: (8)

Couple of hours mate

Disconnect now, watch GP and it be reset

Motion-Mx

iTrader: (2)

haha ok i'll go disconnect it now,Come on Button!