So, I have been reading the forum for the past 3 weeks until my eyes have bled! 3 weeks ago I purchased a 2004 G35 sedan, rwd, 115k (73000 miles). Purchased from first owner with code issues. P0134 - pre cat O2 (bank one). Lets just say because of the code, got for about 3k less than anything listed locally. Replaced with NTK sensor, cleared code and all is good. ($139.00 for the sensor). I have since turned the front rotors, replaced rear rotors, changed out all pads to carbon ceramic (can't believe what a mess the OEM pads leave on the rims), replaced the broken plastic \oem engine splash shield with the Zspeed aluminum shield (50 bucks less than a replacement plastic OEM from Infiniti) and has door for oil filter replacement when changing oil - very practicable and I really believe that in our climate with the sturdy metal construction, will keep rocks and crap out of the engine bay. A lot of very good info was supplied by this forum during all of these steps and thanks to all for their contibutions!!!!!!!!
Now that I have the car back to standards, moving onto the next minor steps. I am at 4000 ft above sea level. As an old fart, getting use to fly by wire throttle reposnse (delay) is sorta frustrating. I have a restored '65 GTO (505 flywheel hp/592 lb feet torque) with a stroker 461 that is immediate response due to mechanical linkage from gas pedal to carb (2x4 bbl/1000cfm's) so, I would like to improve upon throttle response in the G. It would seem that without screwing around with electronics at this point, (remember "old fart" here) I could do the JWT cold air induction and Skunk2 5/16th spacer with relative ease. Looks like previous posts say that breathing would be better to the front cylinders and no reflashing needed. UPREV can also help, but could it not wait until later? Any concern at 4000 ft above sea level? Air is thin - can't tell you how many times I had to rejet/change hangers/tweak timing/ etc on the Goat before good to go and of course, does not have "any" computer controls. Maybe the Uprev (Osiris) should be first before anything else? That would be a downer for me as I am pretty out to lunch as far as computer stuff is concerned, but if that is the way to go, then so be it. Just like to get down and dirty with my own car. Thanks in advance all and sorry for being long winded.

 

Be patient, this might be a little long as well. As a fellow old fart, this used to drive me crazy. I had a 72 442 in the late 70s when I was in high school and I've gotta say for throttle response there's nothing like a cable driven system. For some godforsaken reason Nissan has programmed our throttle plates to only open ~ 75% at WOT and this is a factor in the lag. However, you have a few options to consider to help out.

1. A grounding kit from someone like Black Betty or SxExCx both members here. The merits and benefits of said GK have been debated on here ad nauseum so guys, please don't turn this thread into a back and forth on that subject. I can say it helped my shfting speed and throttle response a touch, enough to notice but not enough to make me happy.

2. Get a Sprint Booster ~ $300. It plugs into your pedal assembly and changes the signal sent to the TB so you get more instantaneous response. Once again, this is a controversial mod as some people love them and some people bash the hell out of them. I have never used one or been in a car with one in it so I have no personal experience to share here.

3. Get an Osiris tune from Uprev. The tune typically would be the last thing you do after any breather mods you are considering; aftermarket cats, intake spacer, exhaust and possibly an intake. Head over to UpRev.com to read up on the tune if you haven't. It's a pretty amazing piece of technology and is a mod I highly recommend, but get it done at a reputable shop on a dyno so it can be custom tuned to your specific car. Among the many benefits it offers is reprogramming the TB plate to open 100% and that takes care of the lag. It also offers customizable maps, raising of the rev limiter, removal of the speed limiter, AFR calibration, timing adjustment, etc.


Other mods you can do to enhance the driving experience which I recommend would be going to a set of aftermarket sway bars like the Hotchkis or Motordyne and swapping your rear diff to a 3.5 or a 3.7. the sways might be the most noticeable mod you can do, the way the car handles before and after is night and day. The diff makes daily driving more fun, but isn't a good mod if 1/4 mile times are important to you. Finally stay away from the Skunk2 spacer, Motordyne is the best brand you can buy if want proven, dyno-tested results. For the most power the stock airbox with a quality drop-in filter is your best bet. Trying to squeeze power out of the DE can get frustrating as the only way you'll see a significant increase is to go FI. I've had my car for 3 years and have installed most of the bolt-ons available short of headers and cams and I have gained 45/43 hp/tq total over bone stock. If you ever have any specific questions feel free to PM me and I'll do my best to help out.

 

Thanks very much Blue Dream. Just got a quote from local auth. Osiris shop. $750/supply/install and as many pulls as ness.