i've searched for hours but haven't really found an answer. i know i'm gonna buy the z tube/jwt popcharger combo as that seems to be the favorite around here. but i'm wondering whats the next thing i should do, i've read that headers do nothing, and i don't want to change out my exhaust because i don't want it any louder. how much hp will i get out of just installing testpipes with stock headers and exhaust. also, how much louder would it be? and how are the hp gains compared to plenum spacers? i just got the car so i'm still trying to learn.

 

Motordyne plenum spacer = 10+ Wheel HP.

 

Go to http://www.motordyneengineering.com/G35.htm and look at their info, dyno charts, etc. I would definately do one if I were you.

 

thanks for the replys, so how much hp am i looking with just ztube/popcharger and 5/16 spacer? i don't want exhaust or anything because it'll make my car louder. would it achieve 240+ whp?

 

Intake won't do anything but change the sound, spacer is an average gain of around 4-6hp across the powerband, peak of around 14hp at like 5500+rpm if I remember correctly. Try searching.

 

If you don't want the car louder don't get test pipes! They will make it louder and raspier.

 

get the greddy evo2 exhaust very low and nice and quiet..i love it

 

Or get the borla its not to loud at all. And you will get some HP out of it.

 

Is there some unseen downfall with the 1/2" spacer? Seems like almost everyone says to get the 5/16"

 

I believe the reason most Gs go with the 5/16 is due to 2 factors: 1) the 1/2" gives more gains at the top end of the RPM range (or so I've read on this forum), but more people who are daily drivers would prefer midrange RPM increases which the 5/16 is suited for, and 2) the 350Z/G coupes can't fit the 1/2" under the strut bar, so most of the used ones for sale are the 5/16. Likely, many sedan owners just get the 5/16 because they see others with it. For these reasons, I think most people go with the popular 5/16. Personally, I have a 1/2" on my FX35 which I love, and I'm looking to install either a 3/8" or a 1/2" on my wifes G35 sedan.

 

thanks for all the replies, it seems like 5/16 spacer is what everyone usually gets, i'm not trying to mod the sedan out extremely, maybe just intake, spacer, and exhaust if i can find a good deal. would i be able to hit 235 whp with those mods? and what would the quartermile look like? i've seen most stock sedans run around 14.5, i want to run a 14.0 or 14.2

 

I did 14.2 with crawford plenum and UR Pulley. Easy to get there.

 

ya spacer is you best option also look at fast intensions exhaust

 

They never made one for the sedan...

 

There are going to be a variety of answers... there is no "one thing is right" mod or set of mods... some have had better results than others but you really need to research the forums and feel comfortable yourself with what you feel will work for you... I have been very pleased with everything I have done but it was all after boatloads of research and talking with very knowledgeable people... Making friends with people that you trust and have done things that work helps in the "give me your thoughts" approach - but just asking for a specific answer out on these boards probably is not the best method...

The things I suggest are planning what you intend to do with the car and what your long term goals are... some people spend a bunch of money of performance mods... then spend a bunch more on 20" wheels If you want looks, and bling, it's futile to go after performance... If you're like me where performance is priority but looks matter, then make sure you have a plan for what aesthetics you will do that won’t hinder your performance.

The other best advise you can get is to read, read and read this site and my350Z - there is a bunch of quality info... granted, you will have to sort out the BS (and there is a bunch out there) but it is the single best way to learn what mods fit your goals and budget.

FWIW - here is what I have done and I have been happy with the results. Not saying you should do the same... but me car has responded very well to the list below - I did things incrementally in the order listed... in some cases a few mods were done at the same time... I've always been happy with various dyno numbers and track times... those results are posted out here and so are research and stats about some of the mods - so no, I wont post all that here.

1) Stillen CAI, Z- Tube, Stillen Exhaust, Stillen ground wires (all at same time)
2) Motordyne 1/2" spacer with Iso-Thermal coolant valve and aramid gasket
3) TS ECU F-Flash
4) Stillen Sway Bars
5) Eibach Springs
6) Crawford HFC
7) TS ECU re-flash
8) Throttle Body Spacer
9) 3.7 FD and Quaife ATB differential

there have also been little things like 350Z lower temp thermostat, Iridium sparkplugs, syth motor and gear oil, thermal coated Z-tube, water wetter for coolant, slightly wider tires, and probably several other things I am forgetting... as you can tell I'm a big proponent of thermal management - I also run a 1/2 cover (recommended or no cover at all).

And a bunch of aesthetic stuff that have no bearing on performance positive or negative.

Hope this helps - happy modding!