Hey all,
I have been a stalker member for a few months on this site. I told myself I wasn't going to mod my 2003 350z Touring, but I gave in and installed headers, test pipes, mini cats (They go in the O2 bung), and a dual 3" cat back (HKS ripoff). Like a few of you already know, after the install of said items the car runs like crap and I need a tune or to restrict the exhaust.

Which brings me to why I am posting. Anyone know someone in the Northern Virginia area with an AccessPORT or some other unrestricted ecu tool? They are not selling them any more and I do not want to shell out 700 for the Osiris just yet. It would be great if I could get some feedback (Positive if you please) on any alternatives you all can think of.

Thanks all!

 

How does the car run like crap?

Do you have any check engine lights?

Also what brand of parts are they and do you have any other mods?

 

The parts are off brand but well made. The car actually runs great, as in it starts and idles and revs like it is ready to rock. Driving normal is no problem. In the higher revs (In or near WOT) it falls on its face. This is a result of the fuel tables being far enough away from what is needed that I assume the ecu starts to pull timing. I did not get a cel the first day, but did get one the second. I reset the ECU and when it comes back I will pull it.

My pathetic mods so far:
K&N filter
Denzo plugs
16lbs flywheel with stage 3 clutch
Headers
Test pipes / Soon to be high flow bullet cats
Mini O2 bung cats
true dual 3" with H pipe cat back

Thanks for the reply

 

Those are good mods man take it easy on yourself!!! You coulda bought a big wing or something.... Then you would be pathetic... Lol (on a stock z)

 

Damn I knew I forgot to buy something! That and flame stickers or peel and stick air scoops.

 

Ptuning in manassas

 

Moved

 

Yea I called them and they do not have a tuner on site for the Z. So if I can find someone around here with the AccessPort that I can rent, buy cheaply, or borrow since it doesn't lock the ecu...I can get a place like ptuning to make the needed changes. Otherwise I am looking at 700 for the tuner and around 700 for the tune. I didn't realize how sensitive these cars are and have never had an issue just upgrading exhaust. Lesson learned...I will save the rest of the mods for when I have a supercharger so I am not in and out of dyno shops.

Thanks for the option though.

 

I have the same problem...i have a 08 350z had it for 3years stock i loved the power it had...i wanted somthing dif for the car and i found a great deal for Greddy true dual Ti-c (3' as well)...love the sound just hate the power loss or torque loss due to no back pressure and not enough air going in and alot of air going out...soon to get my gen3 dual intake hopefully that makes a change...dont really need headers stock are one of the best for the hr...after that and a couple more mods ill do a tune up...mayb go to the one ull find best for the Z

 

Did you keep your cats on? I have read the opposite about HR models. Seems they come with a pretty good set of exhaust manifolds from the factory.

Good to meet ya!

 

Yes i keepd the stock cats on but was thinking of geting resignated ts....n really well i could c it seing how it feels like i lost power...im just hoping on the intakes to some what put me back to where i was

Nice to meet u too how come u never go to meets? Need more Zs out der

 

That is an interesting theory about airflow, but I think you will find that the only way to get the power back and then some is to get tuned. Less back-pressure means more flow and more flow requires more fuel or wider pulses or more fuel fuel pressure (Different ways of compensating). I could be off base, but that is why under normal driving the car seems fine as it is able to compensate via the O2s for the most part. Under WOT the ecu switches to a more static table of fuel enrichment, which is way less than needed. This causes a leaner condition that the ecu makes up for by pulling timing that in turn kills power. I haven't been in the 350z ecu to know if that is how it works, but that is how my obd2 was set up in my Camaro when I used to tune it. You are right though, if you plan to upgrade the intake you should wait to tune until after that is done.

I am too old to do the hangout thing at BK or Hooters (37). If they put together a skyline run or hit the dragon I might come out.

Good luck!

 

For NA tunes at hills garage it's less then 700 for uprev and tune out the door

That's honestly the best way to go

 

I will have to check them out...Thanks

What do you all think of installing a fuel pressure gauge and adjustable fuel pressure regulator and just bump the pressure a few PSI? That would cover the entire rpm range and WOT tables in one go.

 

For NA I would just get the tune and. CAll it a day

 

Dyno the car. If the numbers are unusually low then there's a problem. I made 12hp from test pipes alone before a tune. You probably feel the lowend loss from the exhaust.

 

I don't think I've ever seen a mini o2 cat. Are they more common on domestics?

 

That would be best I agree, but that joint you mentioned is 5 hours each way...yikes!

 

Yea they are pretty awesome...http://bigdaddiesgarage.com/mini-cat-cel-fix.html

 

Little more than loss, more like falls on face. If I can find a dyno near by with a tuning device that will work for my car, I would already be there.

Thanks though!