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what size exhaust is best for an r32 RB25DE?

i currently have 2.25 inch from the headers which was installed by pit stop , after 5 attempts they believe this is the best exhaust yet, it has great top end.

what size do you all recomend?

2.25 " or 2.5 " both with no cat an an x force 2v03 4" canon tip

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Another one of these exhaust size threads again?? Dewd try search before your next thread.

I will nominate 2.5" as it gives a nice mid range and a good top end. I have also had experience with 3" catback that is why I say 2.5". Never tried 2.25" by the way.

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When i got my exhaust done about 3 years ago i had no idea about sizes, i just told the shop to give me the best performance and they installed a 2 1/4 inch exhaust.

feels nice down low and up to about 5000 RPM but after that the engine starts screaming and the power starts to level out. Very nice pull down low tho like i said, makes town driving fun and you don't need to use much throttle.

I'v got a rb25de neo tho, not an r32 25de

Edited by R34 -_-
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  • 2 weeks later...
what size exhaust is best for an r32 RB25DE?

i currently have 2.25 inch from the headers which was installed by pit stop , after 5 attempts they believe this is the best exhaust yet, it has great top end.

what size do you all recomend?

2.25 " or 2.5 " both with no cat an an x force 2v03 4" canon tip

I had a R33 half a year ago with a 2.5 inch catback which i got from a local exhaust shop. straight away after installation i realised the car doesnt pull as hard as the stock and its loud as. But after a month of driving the car seems to adapted to the exhaust and actually went quiet well. 2.5 inch seems to be ok for the Rb25. but make sure you get a good muffler tho as those cheap ones sound crap and drony, and can also get EPA'd which i did. LOL

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i have no idea about the 32's but my car that i sold a few months ago (r34 NA) had a stock exhaust and just yesterday i met up with the new owner and took it for a drive with a new 3'' catback. I must say i was impressed!! a bit slower of the mark but as it climbed the revs i could notice the difference :P

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Really? I would think you would notice a difference straight away with a new exhaust? That puts me off getting one installed on mine

he probably didnt reset his ecu after he put it on so it would have takin a lil while for the ecu to change its settings

in my opinion a 2.5 is about as big as you really wanna go. you can go bigger but theres not much point!

it will give a nice top end over the 2.25 which is still nice in its own way and will still peform just make sure its done with mandrel bends which arnt much more expensive (that includes on a 2.5" exhaust).

and dont be a dick and try and make it as loud as possible, have some respect for others and families (plus less attention from cops)

Edited by Mad-Max
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the amount of 'learning' that the stock ecu does is very little. the HP difference will be very minimal. however the seat of the pants dyno does do a bit more learning. you may do a mod, then have it feel much better or worse, but if you keep driving it you start to get used to the difference and then not notice it as much. having said that, going to a 2.5" system over a stock system if you are going to notice a difference you will notice it straight away. it won't slowly improve. every car i've ever changed the exhaust on, when it has made a difference i've noticed it in the first 100m of driving.

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Yeh i've heard a few times that you can go 3' catback(with a cat) or 2.5' with a cat. Of course with the 3' you are going to loose that low down power but in the higher revs you will notice the engine open up more. I even noticed the difference in power when i chopped off the stock tips with the butterfly valve, now its much deeper but seems a bit slower low down but faster higher up.

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Yeh i've heard a few times that you can go 3' catback(with a cat) or 2.5' with a cat. Of course with the 3' you are going to loose that low down power but in the higher revs you will notice the engine open up more. I even noticed the difference in power when i chopped off the stock tips with the butterfly valve, now its much deeper but seems a bit slower low down but faster higher up.

and unless you spend all your time above 5000rpm then the 3" is just a waste of time and will attract unwanted attention from cars with disco lights on the roof.

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i have no idea about the 32's but my car that i sold a few months ago (r34 NA) had a stock exhaust and just yesterday i met up with the new owner and took it for a drive with a new 3'' catback. I must say i was impressed!! a bit slower of the mark but as it climbed the revs i could notice the difference ;)

3" FTW :(

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lulz. in an N/A 2.5 you'd be going backwards anyway. I didn't even run an exhaust that big on the 5 litre V8 I used to have!

BTW catbacks don't really make any difference for power.

but if you want it to sound like a Lancer dumping out of the headers, then go right ahead :down:

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lulz. in an N/A 2.5 you'd be going backwards anyway. I didn't even run an exhaust that big on the 5 litre V8 I used to have!

BTW catbacks don't really make any difference for power.

but if you want it to sound like a Lancer dumping out of the headers, then go right ahead :down:

yes but you have to remember that half of the older V8's came with the same exhaust size as the 6 cylinders in the range.

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I was referring to aftermarket. 3" on a stock 5 litre has much the same effect as sticking it on a stock 2.5 N/A.

So given that 2.5" is adequate for a stock engine twice the size, why would you go bigger than that? (especially when N/A Skylines don't sound very good to start with lol)

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oh i'm not saying that anyone should go a 3" on a NA skyline because i agree that it is stupid, and the gains made at high rpm are more than outweighed by the losses at low rpm. i misinterpreted your post a bit. when you said "in a NA 2.5 you'd be going backwards anyway" i thought you were meaning a 2.5" exhaust

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