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okai we all know a turbo back might be better but is it value for money? just looking at the prices of some turbo back systems or even getting a cat back and then buying seperate items to form a full system is just so pricey ($1300+)

could someone tell me exxactly how much u benifiet from a turbo back compared to a cat back.

oh and also what are the best kind of exhausts out there these days....ive seen some of the ones where u can mute the sound of the exhaust with a flick of a switch or something?

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Getting a cat back and a pod let my car breath so much better, you really notice the response. That was good but the ECU wasnt up to the task and so I now have modded more and more and I still havent stopped, I plan on getting more soon, should I stop? Do I need proffessional help? I cant stop, when will it end, do i regret it ? NEVER!!

Answer this question -

"What is the restriction to the exhaust flow from the valves back."

Obviously the Turbo Turbine wheel is first but that makes the boost we all crave so if we allow the turbine wheel to get rid of the gasses as easily as possible it will operate a lot more efficently.

The next restriction in a standard system is the actual dump pipe it self in the restricted diameter and shape.

After that problem the major restriction is the CAT itself (Which we cant remove if we have any sense at all)

So after all this, you want to put some larger pipe on the least restrictive part of the system??

Sorry, but it just seems so obvious to me....

I've just fitted a Trust cat-back to my R34 and I've noticed slightly better topend, not much more except for the greater exhaust note. When I changed the dump/front pipe (turbo to cat) on the GTIR which already had a cat-back was massive, alot more then when I changed just the catback on the R34.

Think of it this way using the simple straw/hose theory, you've got a straw at the beginning of the source of water and at half way the straw suddenly becomes the size of a hose. Even though the pipe has now become bigger the flow of water is still restricted at the beginning.

If however its the other way around - hose from the start then suddenly is restricted to a straw, this doesn't sound too good does it? :D

In other words - do the whole turbo-back if you can afford it. If not do the cat-back first then save up for the rest of the exhaust (bigger cat, dump and front pipe) but I personally wouldn't do the dump/front first and have the stock restrictive cat-back.

Looks like TurboX said most of what I planned to right before me. :D

Regarding what exhaust to get: try look for a Jap catback mainly for bolt on issues. Or try going second hand R33 cat-back and then get an exhaust shop to mod it to fit. This is what I did, the R33 cat-back was abit too long but everything else was perfect fit after the longer part was cut. (This is for R34 by the way)

For the dump and front, can't go past BATMBL's dump and front pipe combinations. Look to be of great quality and has most things covered: at least 30cm before the split is rejoined up, pre heat coated, and fixed up the O2 sensor fittings I believe.

Turbo X, I half agree with you.

The dump is a total pos. It is the most restrictive piece of junk in the world - mainly in the shape - how the wastegate gasses are 'jammed' back into the exhaust stream at 90 degree angle.

The front pipe is 'OK' that is, probably not too much of a restriciton for the stock turbo. It's got fairly nice bends and designed quiet well.

The cat is a pos. Very restrictive.

The catback is also quite a pos too. It has poor bends, too many mufflers and furthermore, the mufflers are a poor design. If you cut one open, inside it is really nasty.

1300 isn't that expensive. If you even want to consider doing any other performance mods, i'd finish the exhaust.

Dont worry about buying a brand spanking new system, pick up a used one if its in good condition and you'll save yourself a heap! My car had cat back, so i bought a second hand 3inch dump/front pipe that just jap are selling. Picked it up for $90 and it was pretty much brand new.

Edited by Mr Italy!

I did my own review back in 2003 when I had my R33 GTS-t. I can't find the dyno graph right now (to many pics to browse through) but you can read my old review here:

http://www.skylinesaustralia.com/forums/in...topic=10567&hl=

okai we all know a turbo back might be better but is it value for money? just looking at the prices of some turbo back systems or even getting a cat back and then buying seperate items to form a full system is just so pricey ($1300+)

could someone tell me exxactly how much u benifiet from a turbo back compared to a cat back.

oh and also what are the best kind of exhausts out there these days....ive seen some of the ones where u can mute the sound of the exhaust with a flick of a switch or something?

When I first got my car it had a cat back system installing a highflow cat and 3" dump made a big difference

When I first got my car it had a cat back system installing a highflow cat and 3" dump made a big difference

Hey mate. i got a turbo back zorst with mild steel, and stainless steel cannon and stainless high flow cat from just jap for about 700 bux. gets delivered to melb in a day.

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