benl1981

siks..was this on the dyno - o just seat of the pants? Thanks'

Far out - so a cat back will give you 10-15 rwkw - maybe ill keep mine then. where is most of the gain coming from? The rear muffler? or the pipe? Maybe I get the stock rear pipe and then fit a higher flowing rear muffler.

I was under the impression that in a turbo car where it comes out of the turbo all hot and expanded is the most important part to have less restrictive, allowing turbo to spool up more easily.

Are these the same as an R33Gtst one? I was hoping they might be a bit less restrictive... Anyone got one going cheap? Thanks Ben

mister minit had one for my r33 - just went down there and said I need this cut - nissan! $6 oh sorry just read above...

anybody got a pic of a standard Gtr muffler? thanks

I'm chasing one in good condiiton - standard. Hopefully one in sydney for $20-30. Thanks Ben

what sort of a rear muffler does a standard gtr have - would this be a good compromise? thanks

do you have the gear knob? What condition is it? Thanks Ben

anyone?

That's pretty dangerous for you and more importantly other people! If you don't respect your own life atleast respect others. In the right environment it's ok - Take it to the track/drags.....please.

About how long does it take to set up this part 2 and approx cost of all the components?

thanks Siks. Do you know which part is restrctive? the fact that it is 2.5" or the resonator/middle muffler or the rear muffler. I tought the dump was the most important though? Not true? Mines prety quiet in the cabin, just people notice it when your in the carpark or something. Not real loud but people do turn around sometimes...

anyone? Anybody just upgraded cat back and felt much difference? kws? 1/4 mile times? Anybody just upgraded the dump/front and felt much difference?kws? 1./4 mile? Thanks

Thanks for the feedback. I have a kakimoto cat back on a the moment (3/12 inch) with standard dump/front. I have a 3" dump/front ready to go on but I'm thinking of picking up a stock cat back. The kakimoto is fairly quiet but I have recently driven a few stock skylines and like the quieter exhaust. So how much would I lose running fairly stock boost on RB25DET (7psi) by putting the stock cat back on rather than the kakimoto? Would it be a fairly even power trade if I put the 3" front pipr/dump on rather than having a good cat back section? Thanks Also how restrictive ar the standard nissan rear mufflers? Are tey universal between all the turbo nissans? if you chopped out the first rear muffler/resonator would the system still be quiet yet flow better?

Hi there. I was wondering if anyone knew how many kw a good cat back exhaust will gain in rear wheel kw. Will the dump alone with standard cat back give more gain than say a 3 1/2 free flow cat back with standard dump and front pipe? Thanks

True about the officers DG..but how easy would it be if thieves/speeding drvers knew all they had to do was speed a bit and they will get away from the cops. Maybe the cops need more stable cars...awd and /or a better system in place to coordinate other patrol cars and set up road blocks etc, Not something that will be solved here but I can respect what the cops do for a living, even if there are some bad ones. Like with everything

I don't believe that. a 5psi actuator is a 5psi actuator. They are tapped into the inlet pressure to control the wastegate flap to maintain this level of boost. The difference that an exhaust would make would be similar to the differnece between eg. High load and low revs in 4th…this allows boost to grow quicker, compared with say flooring it in 1st from low revs…there is less load so boost doesn't reach its maximum till a little later in the rev range. The actuator still maanages to maintain boost at the predetermined level no matter what the scenario.

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A lot of magazines and on forums people say - fit bigger exhaust and you will gain a psi or 2 but I still can't understand based on what I wrote above. Most factory actuators will open slightly before the 5psi or whatever boost they are designed to hold boost at. This is so that there will be no boost spikes etc. ....Ok listen to this: The wastegate will always dump enough boost before it gets to the desired level so that it vever exceeds this figure. With the new exhaust it may make the boost easier and with greater flow. however the peak boost should be the sameI think if the actuator is left unchanged.

I still find this hard to understand as the pressure the actuator sees is tapped into compressor outlet (Or on most turbos anyway). If it's configured to hold boost at 7psi...then it should do this no matter what - that's what it is there for. Obviously the turbo will be more efficeint with less back pressure but really if you have a 5psi actuator thats what it should be fully open at - and open before to maintain that as a maximum. This is the first turbo car I've had and I haven't played with boost so I don't know the practical side of what happens when you free up the exhaust. I would have thought that the wastegate should just open earlier with a better exhaust to maintain the same psi. It just may get to peak boost earlier.

Hey Arkon - did you notice much power gain?? I've got a 4 door like yours I'm thinking if I fit in and find it too noisy I might put on a standard cat back and sell my cat back...although I would have to source the standard cat back. The dump/front alone would be more of a gain than the catback right? Is the standard cat back that restrictive? turbo to cat - batmbl does them on these forums for 250...

I'm thinking of going a 3" combined front/dump bellmouth style one..will this increase noise you think? Maybe I should just go the front pipe upgrade (without the dump), but then will that be worth doing? Hmm - hard to know...thanks!

Anybody know about this - I'm trying to decide... would be perfect if somebody had a cat back that was fairly quiet (about 3.5") with stock front exhaust - then swapped to 3" front dump and could tell me how much noiser it was!!! Thanks

Really - thanks for the tip. Might forget it then! I was possibly going to up the boost to 10psi and I thought this might be a safer way. I dont want a front mount though. Anybody know what the pressure drop across the 2 coolers is or intake temps...to compare