Turbo back exhaust waste of $$ or good upgrade

[ISC]

Sorry to start another thread but I've searched/googled the topic for quite a while and keep on hearing different things ranging from 10-15kw gains, to less kw but more torque and also that because of the ecu the larger exhaust is a waste of time/$$.....

Before I hand over the $$ for a turbo back system can people that have done the upgrade comment about power increase and if you have any before/after dyno's that would be even better!

My Rcolt currently has a Greddy intercooler kit, Colt speed air box, Trust PE 2 diff back exhaust, GFB blow off valve and is running 1 bar (14.7psi) boost.

[Ayu452]

i lost about .1~.2bar of boost fittin the exhaust...got a YR tip + rpw front pipe and cat replacement system...
but it does pull to 180 alot faster...very nice topend...can't wait to fine tune the boost and bring it up...its gonna be nice...gettin the dump pipe and dyno on tues let u no
and lots of angry sound ^_^

[daedalusjc]

dump pipe, smashed out middle cat and $90 custom bent piece of pipe from rear muffler back. Dump pipe's the key. Goes hard and less spike with low end spool deluxe

[ISC]

Iam guessing ecu flash is the same as a remap? I thought this wasn't available yet going by the forums I've read etc, or do you mean just set the car up and wait untill it is available? Just worried as a friend with a VR4 also did an exhaust upgrade and lost around 20rwkw, as far as I no there ecu is very similar to the Rcolt? (hard to crack).

[koshy]

tmr_colt means you tune the car once with all the upgrades you have (eg. exhaust, dump, manifold) so you dont have to do it again after you put another mod on. If that makes any more sense?

[ISC]

yea yeah completely understand that, but I'am asking if the tuning/flashing was avialbale for Rcolt ecu as yet?

[ISC]

ok, I might even have a word to a couple of local ecu guru's about remapping etc. But back on topic, please let me no about your performance gains/loss's with a turbo back exhaust.

[Frogman]

I noticed a gain with only a cat back exhaust... With full turbo back I'd imagine there is even more to gain

[Macca]

someone made a serious mistake if your mates car lost 20kw

i have never seen a turbo car loose from exhaust upgrade

unless they made is like reducsley too big

[daedalusjc]

yeah 20kw alot of power. Perhaps they didn't compensate in other areas. I.e boost dropped, wrong cats, oxy in wrong place, didn't reset ecu, badly designed exhaust and/or down pipe housing. Many things but you certainly wont lose power on colt

[underdog]

Gday, just go to the RPW website and take a look at their R&D on the rcolt[specifically on the exhaust and you will see all you need to know] and even call mitsiman, im sure he will help you out as he did for me [ i bought his exhaust and cant wait for the manifold and dump housing to be done], cheers:)

[filofaith]

someone made a serious mistake if your mates car lost 20kw

i have never seen a turbo car loose from exhaust upgrade

unless they made is like reducsley too big

i was the only one from memory to loose power from my exhaust,

now what i asked for was a straight pipe 2.5" exhaust that goes into a 2.5" twin tip... now they only did from the 1st cat all the way back (one cat removed) and no resonators or mufflers... driving it was a pain as it was VERY VERY SLOW and sounded like a tractor...

well now your second thinking the exhaust... well i added a muffler and resonator... and you can definately feel it working now... something about too much flow?? beats me i duno get it, i thought turbo cars need to breathe i was wrong...

so yeh if your going to get an exhaust get the FULL exhaust meaning dump pipe and all remove one cat but make sure it has a muffler and maybe even a resonator thats my advice and stick to a 2.5", you'll have nice power after that is done :)

[ommeh]

I believe the reason why some cars lost power to the Exhuast is becuase of our ECU. Normal turbo cars will want as much free flow as possible. Dont go over 2.5" in your exhaust and to answer your questions YES it is a must get for any turbo car. Even tho you may loose a little bit in kw but you will def increas your nm in torque. I've only got the Catback and even so it was so much more responsive and the car came alive. Great sound and it was well worth it.

Seeing you have Hiso's car and hes already got a Diff back, what i would suggest is you get yourself the RPW down pipe and back back system. All you need to do is weld flanges onto the end of the GReddy exhaust and connect it to the RPW exhaust. I garantee you will not be disappointed. When a remap comes and you can tune your car to its best you def want to have the exhaust up there during the tune :)

my 2c's anyways lol~

[filofaith]

I believe the reason why some cars lost power to the Exhuast is becuase of our ECU. Normal turbo cars will want as much free flow as possible. Dont go over 2.5" in your exhaust and to answer your questions YES it is a must get for any turbo car. Even tho you may loose a little bit in kw but you will def increas your nm in torque. I've only got the Catback and even so it was so much more responsive and the car came alive. Great sound and it was well worth it.

Seeing you have Hiso's car and hes already got a Diff back, what i would suggest is you get yourself the RPW down pipe and back back system. All you need to do is weld flanges onto the end of the GReddy exhaust and connect it to the RPW exhaust. I garantee you will not be disappointed. When a remap comes and you can tune your car to its best you def want to have the exhaust up there during the tune :)

my 2c's anyways lol~

get RPW dump pipe down pipe and catbak system (just tell them you already have a Diff back) and youll be good :) when the ECU comes out youll be making decent numbers

[pAuL]

now what i asked for was a straight pipe 2.5" exhaust that goes into a 2.5" twin tip... now they only did from the 1st cat all the way back (one cat removed) and no resonators or mufflers... driving it was a pain as it was VERY VERY SLOW and sounded like a tractor...



that's exactly what i have now (bar the twintip) and i done have the same problem

[lovecolt]

Filo: Turbo needs big flow of exhaust, which is correct. But it will still need a certain amount of back pressure, therefore your straight through system might be too much. This is why exhaust manfacturer will have to do their R&D to reach the balance.

ISC: If you done it with the commonly agreed size of 2.5 inch, i have yet to see anyone make a loss on the dyno. Macca and Adam both (similar mods) registered mid 110s fwkw with their exhaust on the same dyno.

[ISC]

Going by this thread I will be getting the turbo back done soon. Will be getting a custom job from E.T here in SA (very good quality). Once it's done I will post up some results.