Gino's 300zx build

[DCaff300ZX]

I hear ya, been fighting mine some as well...just took it in to my Z guy today for (hopefully) final dyno tuning and a new fuel pump installed. Not sure you knew, but I've had some engine work done while fixing some stuff- new turbos and smics and a few (OK, lots) other goodies while getting her sealed all back up, and new clutch and shifter work. I MAY still have to buck up some extra dinero for a new standalone, as I found out today mine (Apexi PowerFC) actually is not a piggyback but is not much more, just a lower-cost standalone variety with no barometric sensors and other controls which limits my tuning range- possibly too much for my tastes hence perhaps needing more adjustability. I'm just hoping he can tune her out right this time after adding a new IACV last month.
These damn things just take awhile to sort out when you mod them too much, especially if there are any gremlins in the system.
Good Luck and keep us posted!

[Gino]

Well made its first official "post build" trip...my brothers shop hosted a car show for Fall Fest and obviously I was invited. I was the only import, but some other nice cars were there. It was a 30 mile (round trip) drive and she took it like a champ! She is in desperate need of an alignment (I did a basic string alignment but obviously it needs to get on a rack) but she drives nice, albeit pretty damn loud lol. It will get an alignment as soon as the rack at my brothers shop frees up. Anywho, here are a couple pics from the show.





I am holding off getting it on a dyno until next year..we are buying a new baby hauler (either a CX5 or Rogue), I have some cabin wiring gremlins I need to sort out (possible mouse damage? Interior lights not working and stereo not getting power and its not a blown fuse), and mostly I just want to put some more miles on the motor before going crazy on it. As soon as we get the alignment done, look for a fall photoshoot!

[Gino]

I hear ya, been fighting mine some as well...just took it in to my Z guy today for (hopefully) final dyno tuning and a new fuel pump installed. Not sure you knew, but I've had some engine work done while fixing some stuff- new turbos and smics and a few (OK, lots) other goodies while getting her sealed all back up, and new clutch and shifter work. I MAY still have to buck up some extra dinero for a new standalone, as I found out today mine (Apexi PowerFC) actually is not a piggyback but is not much more, just a lower-cost standalone variety with no barometric sensors and other controls which limits my tuning range- possibly too much for my tastes hence perhaps needing more adjustability. I'm just hoping he can tune her out right this time after adding a new IACV last month.
These damn things just take awhile to sort out when you mod them too much, especially if there are any gremlins in the system.
Good Luck and keep us posted!

Yea they can definitely be finicky lol. I actually ended up deleting my air regulator (still have iacv for now) since it was leaking and causing the idle to search/be unstable. One of the wonderful things about standalones lol.

Sounds like you got some good upgrades while you were in yours! The PowerFC is nice, but as you said it definitely limits tuning. If you want to stay at a "low" price point, go with nistune. Unless you are on crazy big turbos with all kinds of different inputs like me, you don't necessarily need a $2,000 standalone ems.

[DCaff300ZX]

I hear ya, been fighting mine some as well...just took it in to my Z guy today for (hopefully) final dyno tuning and a new fuel pump installed. Not sure you knew, but I've had some engine work done while fixing some stuff- new turbos and smics and a few (OK, lots) other goodies while getting her sealed all back up, and new clutch and shifter work. I MAY still have to buck up some extra dinero for a new standalone, as I found out today mine (Apexi PowerFC) actually is not a piggyback but is not much more, just a lower-cost standalone variety with no barometric sensors and other controls which limits my tuning range- possibly too much for my tastes hence perhaps needing more adjustability. I'm just hoping he can tune her out right this time after adding a new IACV last month.
These damn things just take awhile to sort out when you mod them too much, especially if there are any gremlins in the system.
Good Luck and keep us posted!

Yea they can definitely be finicky lol. I actually ended up deleting my air regulator (still have iacv for now) since it was leaking and causing the idle to search/be unstable. One of the wonderful things about standalones lol.

Sounds like you got some good upgrades while you were in yours! The PowerFC is nice, but as you said it definitely limits tuning. If you want to stay at a "low" price point, go with nistune. Unless you are on crazy big turbos with all kinds of different inputs like me, you don't necessarily need a $2,000 standalone ems.

Yeah, she's VERY happy now for performance even without a mega-build, the 530bb turbos are super-nice and the exhaust porting really also made a difference in acceleration. I have been going back and forth on what to do with the few PowerFC issues and actually things have stabilized just a bit more, but it still on occasion such as today start holding a 1500 idle too long, and then also start hunting bad until I shut it off for a second or two and restart...which today still did not immediately make it stop. Then on the way home, perfect and purring (or roaring) like expected.
Another small gremlin at this point is a small misfire that will go away when the engine temp hits or goes above 83 degrees celsius (PowerFC readout) and everything stabilizes completely. Before then it will be choppy at idle and off-throttle and even backfire a little under heavy decelleration.
What do you think?
I'm looking at a cooler heat range sparkplug change if a PTU harness clean yields no results, any other thoughts or advise?

[MrFeesLaw]

Sick build man! Getting mine torn down next week. Don't think my engine bay will turn out that clean though! A clean engine bay only exists indoors where I live. Great thread. Love your rims!

[JayNoel]

Love the car!!! Carry on

[Gino]

Thanks guys. Once this s*** weather clears up over here on the east coast ill drag her out for a nice little photoshoot

[Gino]

Yeah, she's VERY happy now for performance even without a mega-build, the 530bb turbos are super-nice and the exhaust porting really also made a difference in acceleration. I have been going back and forth on what to do with the few PowerFC issues and actually things have stabilized just a bit more, but it still on occasion such as today start holding a 1500 idle too long, and then also start hunting bad until I shut it off for a second or two and restart...which today still did not immediately make it stop. Then on the way home, perfect and purring (or roaring) like expected.
Another small gremlin at this point is a small misfire that will go away when the engine temp hits or goes above 83 degrees celsius (PowerFC readout) and everything stabilizes completely. Before then it will be choppy at idle and off-throttle and even backfire a little under heavy decelleration.
What do you think?
I'm looking at a cooler heat range sparkplug change if a PTU harness clean yields no results, any other thoughts or advise?

First issue with the high idle i can't help you..Im not too familiar with how the power fc works in that respect...but there is the possibly it could be related to the second issue. Second issue with the choppy cold idle/driving is in the tune...until you reach operating temperature cars usually have a cold start enrichment map which essentially dumps more fuel in until it's fully warmed up. The extra fuel helps vaporization (when everything is cold and fuel is introduced it tends to condense and puddle in intake runners, etc, not making it into the combustion chamber, which is no good for igniting..this is the idle surge and afr instability). Adding more fuel on cold start ensures that enough fuel gets to the combustion chamber for proper ignition. Im not sure if the powerfc can control cold start enrichment, but if it can then you need to add more fuel...

[zunich]

Nice read from start to finish. I will stay tuned for the "Dyno Tune" pun intended. I want to sincerely thank you for taking the time and effort to post pictures and write about your experiences. This kind of first hand info has enriched the knowledge of everyone and am sure it will help me after I purchase a 300zx (hopefully in the next couple of weeks just waiting for the guy to drop the motor in). Till then living vicariously though your great posts. All the best to you and yours. John Zunich Long Beach, CA

[Gino]

Thank you John. Goodluck with your future Z purchase, and definitely keep us updated on what you find! I hope this thread has given you some inspiration for your future Z!

[madxman21]

Bad a**. I love it Gino!