Low HP on 240, help!

[Mixmastamunkh]

So I just bought a 91' 240sx, with 114 k on the chassi, with an s14 engine and transmission swap in it. the engine/transmission only has 40,000 miles on it. it has an injen cold air intake and a catback exhaust with a 2.5 muffler. my friend said that i would be LUCKY to get 140 hp out of my car if i took it on a wheel dyno. what is the real deal with these cars on dynos? is the wheel dyno significantly different? please give me some first hand accounts or some advice. I'd REALLY like to make it significantly faster. any idea how i can make it faster? for somewhat cheap.

[240marcuSX]

you wont make 140 at the wheels with those mods. my bet is that you have about 165 at the crank translating to about 130 at the wheels, i think.

get lightweight pulleys, header, cams, headwork, the list goes on and on.

[:: orion ::]

140 sounds about right...

155 CRANK HP form the factory is about 125-130rwhp when dyno'd. I have seen many stock dyno's in that range.

Now, intake and exhaust will add 10-15rwhp or so...so I could see you laying down 140rwhp.

What did you think it would do?

- Brian

[Red coupe]

intake an exhaust will real add a full 10-15hp at the wheels? thats actualy better then I would have though...would that still be aplicable if I got exhaust with huge resinator (i woulnt want much louder then stock exhaust)?

didnt I just read about this in technical?double posting= only 7 minuts apart too...

[Mixmastamunkh]

sorry about the double post. i realized i posted it in the wrong section after i posted it so i copy/pasted it where i origionally wanted it.

[Pank]

intake an exhaust will real add a full 10-15hp at the wheels?

I honestly dont think it will make that much HP. Maybe with head work/cams/headers it would make a difference, but not on a stock NA KA

[Dattebayo]

Header, damn it is F%&*ing singlar on a I4.

I go crazy when people say that! But you should make 10 or more by having a HEADER Exhaust and Intake.

[toptechracing]

Header, damn it is F%&*ing singlar on a I4.

I go crazy when people say that! But you should make 10 or more by having a HEADER Exhaust and Intake.

It would be singular if it were a 1 piston engine. You are dealing with multiple header tubes ending up in a collecter. That's how you get the term headers even on an L4.

[2s4x0]

go to any site and look at buying a header, they ALL say HEADER, singular, not plural. every site whether they are talking about it or whatever it says HEADER. It might be multiple header tubes, but the entire thing is called a header. Might not be perfectly techinically right, but bottom line is the thing is called a HEADER, singular.

[Dattebayo]

Header on I4

Headers on V6, V8. You get it?

Not very informed for a racing guy. And youre the olny one in have seen who has EVER said that before...

[SloMoe]

Header on I4

Headers on V6, V8. You get it?

Not very informed for a racing guy. And youre the olny one in have seen who has EVER said that before...

Umm who cares what he wants to call it, your point doesnt even pertain to the subject at hand. Damn why does that make you so mad?

With that aside when I did a baseline dyno on a DynoJet with a bone stock S14 motor, it put down 136HP/145LB.FT. of torque.

[B-TownSX]

if you don't care for emissions or law, you can get a replacement CAT (straight pipe) for about $30. There's some cheap easy hp gain right there. Just remember that installing an intake system with ram will only help on mid to high range, it took away from my low range signifigantly. I kinda wished i never did it. It does look sexier.

[coolcloo1019]

all i have is 2.5" catback exhaust and testpipe and i put down 141hp and 141 lbs/tq

[Ni2s4s0aSnX]

somewhat cheap mods to boost horsepower on the 240sx are, well, first you'll probably want to put a bigger exhaust onit. I would go with either the Apexi GT spec exhaust, which is a 3.74 inch exhaust, the Apexi N1 dual catback exhaust system, or the Invidia N-1 high performance cat-back exhaust. The GT spec, you can get for around $400 on http://i-m-racing.com/. The Invidia exhaust, you can get on Performancecenter.com for about $600. And the Apexi N1 dual exhaust you can get for around $500 on I-M-Racing.com. Other somewhat inexpensive mods are intakes. You will probably want to get an Injen intake, which you can get for around $200 on I-M-Racing.com, and you can get an Injen cold air intake extension on Performancecenter.com for around $120. You will probably want to get a custom made intake though, and relocate the battery, if you are looking for performance, because the intake tube will be shorter, which will increase throttle response, and your intake wont be running on top of the hot radiator. Also, high performance, spark plugs and spark plug wires can add a few horsepower, and it is a very cheap mod. Of course replacing the header is a good mod. I would recomend the DC Sports 4-2-1 header, even though most people would disagree, Dc Sports has a good name, and their product is street legal, and its not like you dont get as much horsepower with the DC Sports header, 12-14 horsepower gains, and you can get it on http://Modacar.com, for around $400-$600. Also, fuel injectors, and a new ECU, can get you some good horsepower. Venom, makes good injectors for the 240sx, and Jet is a good ECU. You can probably get up to 35 horsepower out of that combination, but for around $600. Also, another cheap mod for the 240sx, is a new cat converter. Carsound makes a good cat converter, you can get up to 10 ponys out of it, and for only around $100. http://Performancecenter.com has it. And im pretty sure HKS makes a cat. converter for the s13. I hope these mod suggestions are helpful to you.

Modified by Ni2s4s0aSnX at 11:58 AM 5/10/2005
Modified by Ni2s4s0aSnX at 11:59 AM 5/10/2005

[240DRFT]

i highly doubt u can get 10 hp from a new cat

[KAcoupe]

lol 3.75 on an na HAHAHA tak abou tno back pressure i doubt that he would even be able to get out of his drive way....get a hot shot header best in the biz... no more than a 2.25 exhaust keep your stock intake but add a k&n filter to it...already state why in pervious post just look it up..as far as ecu's id got with jwt..they dont specialize in nissan's for no reason that should bump you up a bit then get a ur pully and a nice diff and you will be fine might not have the big numbers but you will pull of the line and say halla try to catch me for not to much money...wont be the fastest but you will be quick