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it's always much more challenging (and expensive) to mod an N/A car sucessfully. As NA_R33 said, exhaust, extractors etc will give you a much better breathing engine, but I'd be very careful about choosing which products to use - a lot of the big bore aftermarket exausts will cause you to lose a lot of low end power/torque, which is exactly what you dont want...:)

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As an example of what I said above, fujitsubo provide quite detailed info on all of their exhausts - here's what a typical power/torque graph looks like:

LegalisR_torque.jpg

Notice power and torque are way down under 3K rpm, but pick up and improve at higher revs. I'm not saying this is typical of all exhausts, but you do have to choose with care, especially with N/A...:)

Dave

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with all due respect, i have driven a R32 rb20de before with catback exhaust mod before... the car actually felt weaker. The torque is almost completely gone becos there's not enough back pressure for that push. dun forget that you are driving a heavy car that needs plenty of torque for that push. even for my car, rb25de, i felt a decrease in torque but gain abit of it back when i fitted in a silencer... its better balance now at both low and high end power.

my advise is just the air pod and thats it. any other mods like ecu or engine internals are waste of money, esp for an NA car.. trust me, i was in your shoes a while ago and decided to concentrate on the handling of the car instead... such as struts and sways, etc...

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I have to agree. At my local circuit most of the N/A racers (civics mainly) always use a small bore exhaust to keep back pressure up. On my current car there is a definite difference in the bottom end power/torque when I add or remove the tail pipe baffle. Generally speaking, if you go for an aftermarket exhaust avoid anything too big and make sure it's designed/tuned for an N/A engine...

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I had a exhaust made up at my local place for my old GTS, was 2¼" and only had a (large) resonator near the front and a smallish muffler at the back and picked up about 8Kw at the wheels and lost no low down torque, picked up quite a bit in fact. However seeing some GTS's fit 2½" exhausts they did loose low end when redyno'd.. and that includes GTS25's.. but your only going to get fairly small gains no matter what you do in an N/A car... including PVA's suguestion of NOS as I don't think a RB20DE will handle much more than a 50hp shot???

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Try and get your hands on the last issue of HPI (high Performance Imports mag. It has a white GTR on the front with 900hp.

The is a great story on a N/A 180sx which the guy is trying to get 100rwkw on a tight budget. At the very least it will give you some good ideas for your skyline

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internal work is not required for a 70hp nos kit on a gts25 so i dont think 50hp on the 2 ltr would require ne. People have presumptions that nos destroys engines, when used properly, yes it puts more stress on the engine as with ne modifaction but actually allows the engine to run alot cooler due to the chemical reaction that goes on in the combustion chanber which is very benificial to engine.

Has nebody ever considered a computer capable of a dual fuel curve with extra injectors for methanol on the second curve, thereby allowing the engine to be leaned right out with out pinging due to the much cooler methanol running through the engine and giving a considerable power increase kinda of like not so illegal nos?? just a thought....

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Just do a search on it and see how it works. Basically the nos is broken down by the heat of the engine and when it is broken down it produces oxygen, as the reaction requires heat the process thereby draws heat out of the engine and therefor cools it down.

PVA_GLUE: Thats exactly what im saying, Obviously there will be more stress on the internals but the lower combustion temperatures kinda cancel it out, of course this is only when running relitivly small doses, say 50 to 75 hp.

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Extractors for a RB25 will set back around the $2500 mark. Thats a rough price so call up, but it's not cheap as far as I know. I agree with the bigbore 3" zorst, unless your car can push out that much it can potentially drop the power levels.

Much like a front mount intercooler on a GTST vs the stock one. Because the air has travel much further it takes longer and looses pressure (aka pressure drop). Thus you may be required to run say 8psi instead of 6psi to get the same power than before you had front mount.

However yes the front mount will handle much more boost anything above 10psi whereas the stock may not

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