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Hi all, i seem to be a having a few issues in all aspects about my new exhaust system....

I have a 3" Split Dump/Front Pipe and 3" Hi Flow Cat with a 3" catback part and 5" cannon output...its annoying me in so many ways....but anyway,

issues aside.....will my stock cat back exhuast connect fine to the aftermarket xforce cat? and this should quieten my exhuast down shouldnt it...its gotta be a better combo than stock dump/front and cat.....?

or would i be better to put the whole stock exhaust system back on?

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if you put any portion of your stock system back on, you do realise you will loose power.

ot will be ok to put the stock cat back back on, but it will reduce power and be restrictive.

whats wrong with the system on it? too loud? too ugly??

if you put any portion of your stock system back on, you do realise you will loose power.

ot will be ok to put the stock cat back back on, but it will reduce power and be restrictive.

whats wrong with the system on it? too loud? too ugly??

i highly doubt im gonna lose much power...i have got less power now with the aftermarket system on than i did b4.....go figure! its got everyone stumped.....

but anyway, its too loud for my liking.....and is causing huge fuel consumption issues...and other stuff like that....

Edited by WOG BOY

if you lost power fitting a 3" turbo back exhaust system, then there is another issue there. no way should you loose power. you should gain power, and feel it too. it should be running a few extra pounds of boost too.

you might have a vaccum leak somewhere.

ahh im jus gonna take it off and put the stock cat back on it...leave the split dump and front pipe as well as hi flow cat on it.....

jus gonna make the car more showy.....it probably makes no sense...but i got enought power to beat all the commodore heros round my town...im happy with that!

:)

You definately have another issue. That exhuast should give you a noticable increase in power. Also, if its too loud, that seems strange, unless you like a really quiet car :( The turbo acts almost like a muffler in the exhaust system, so turbo cars with exhaust are fairly quiet compared to NA cars.

Increase in boost level from aftermarket exhaust should lean out the A/F (Air / Fuel) ratio,

which makes the engine produce more power.

I wonder if the stock ECU has switched to the low octane maps that has the retarded

igniton map and richer fuel map. I guess a richer A/F ratio would explain the power drop.

What octane fuel do you use????

It should be at least BP 98 octane.

Have you reset the stock ECU by disconnecting and then reconnecting

the battery????

Edited by SKYPER

i have been using either CALTEX VORTEX 98 or SHELL V-POWER....

no i hadnt done an ecu reset.....should i do that?

is it only jus disconnect the battery then join it back up...or do i have to leave it off for a while?

also the cat that i bought was a 'XFORCE HI FLOW CAT' and i was speaking to the exhaust shop just before and he said that it was a 400square per inch or something....where as his hi flow cats were only 200 square per inch.....so his would be less restrictive.....

what should the measurement be of the high flow cat......? (if any of that last bit made sense....)

Try it and see if there is a difference. It should temporarily clear fault codes, reset ECU to main ignition, fuel maps.

If there is a failed sensor or something else is wrong, it probably will revert back to what ECU was set to before

resetting ECU.

I think you remove the negative first and cover up the negative terminal with a cap. This is to make sure you dont

touch the positive terminal + negative terminal or positive terminal + chassis which is connected to negative terminal.

This could happen when you have a spanner in your hand and get a nasty surprise. Then remove the positive cable.

Reverse this order when reconnecting battery with positive first and negative last

Don't know much about cats, but I would think that a bigger volume cat would flow better.

Edited by SKYPER

alot of people have been telling you that you obviously have an issue that isnt related to your exhaust thats making you loose power and from what you have been saying you have had this issue long before you got the exhaust.

if i were you i'd just take it to a workshop to diagnose it. they will hopefully fix the problem and then you will be glad you had left the aftermarket exhaust on.

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