MXjunkie926

2004 350z, factory internals. Have CP 11:1 pistons, Walbro 155lph fuel pump (I think), AEM FPR, factory crank with HCL tri-metal main and rod bearings. All these parts I purchased a LONG time ago when I spun damn near every rod and main bearing in the motor due to a nasty lubrication problem. My only question is, since I don't want to spend unnecessary money on this car for a while, do I need to
A: upgrade more such as cams and injectors to run the CP pistons?
B: sell the pistons, put a stock motor back in it and just have fun with the suspension components on the car in the turns?

Just have no clue any more since its been 4 years since I've read up on the Z tech or done anything with the car. I don't know if the fuel upgrades are necessary with an 11:1 compression ratio based on the engines factory dynamics. Thanks for the help guys.

J.$

iTrader: (1)

Your post is kind of confusing, lol.

The motor in the car right now has spun bearings?
CP Pistons and ACL bearings are not installed?
Walbro doesn't make a 155LPH pump but they make a 255LPH, that's what you have?
How much money are you willing to throw at this?

MXjunkie926

Sorry for the confusion. Typed it up in a financial meeting at work to keep from falling asleep. I have all the parts listed NOT installed, motor is torn down completely and sitting on an engine stand wrapped up in plastic. Just needing to know if the injectors, fuel rails, cams and such need to be upgraded or can I use factory parts and just throw the pistons in there with a good tune. The car currently has exhaust, headers, JWT pop charger, kinetix ssv manifold and other small exterior mods. I was 18 yo last time I even touched the car and really had no business working on it due to my lack of knowledge and funding, things have changed since. If I can't use the pistons without having to throw money into the cams and other parts, then I just plan to sell them and get the motor running stock just to have a fun car to drive again with my wife on the weekends until I can afford to do the things to the motor I want. Hope that clears things up.

J.$

iTrader: (1)

You could just use those pistons with a factory motor IF everything in that motor was in good condition.

Since you spun multiple bearings I would have EVERYTHING in the motor checked by a machine shop. What size did you buy the bearings in? Your crank is most likely going to need to be machine so if you bought standard sized bearings, they won't work. If that's the case, your options would be to purchase a new crank or buy different size bearings.

MXjunkie926

I've already purchased a turned crank and bearings were sized by the machine shop that sent me the crank. I WILL be replacing the rods because the seat was screwed to hell on every single one and WILL have the entire rotating assembly balanced. I guess it would have been helpful to tell everyone that when the bearings were spun, it was on all factory internals. All the parts I have in my possession were purchased AFTER the motor had its issues. I've flushed out the valvetrain and all oil passages throughout. Every single part damaged or left over from the original motor is either being replaced with OEM parts or upgraded to aftermarket parts. Like I said originally, my only real question behind all my rambling (for which I apologize), was to find out from some people if it was safe to run these new higher compression pistons on factory injectors, fuel rails and cams? Just want to make sure I can get enough fuel to the motor via factory supply. I didn't know if the factory injectors and cams were enough air/fuel supply to ensure I wouldnt see a lean air/fuel ratio...not because it doesn't receive a proper tuning, but because the factory injectors were maxed out and just didn't supply enough fuel. Thanks for the continued help and advice. The few shops I've called, to include Jotech, have told me that I needed an inordinate amount of fuel upgrades to even think about running these new pistons.

terrasmak

iTrader: (8)

Stock injectors are good to about 280 to 290 whp , rods are fine , but I would swap to ARP rod bolts , cams are not needed. Really the pistons will not do much till you do the whole package

MXjunkie926

Thanks a ton guys for the info. Don't really care if they do too much for the gains in the car, really just wanted something with a little better response and make sure it's reliable enough to not blow up on me like my dirt bikes. Thanks again for the help and have a great day guys!

Moderators, feel free to close thread because I'm not computer savvy enough to figure out how to do that.

J.$

iTrader: (1)

You will not need new cams and I wouldn't worry about the rod bolts either. There are guys making 400 rwhp with factory rods and bolts. I would however get a larger set of injectors, that is all.

terrasmak

iTrader: (8)

Rod bolts are the weak link on an NA motor that is typically revved a bit higher to get power. Till the OP has long tube headers and a lot of other work , injectors are not needed.

Rod bolts will help set him up for future NA power gains if he decides to

redline06

while you have it all apart might as well do rods too, Cams would go hand in hand with good long tube headers.
edit* and if you do cams then do springs and a retainers to rev the **** out of it lol

MXjunkie926

I have EL headers on the car already and just ordered a set of Manley Hbeam rods with the ARP-2000 3/8" caps, or whatever they're technical name is, to throw in there. Trust me, the rods from the original issue are trashed. Thanks again guys for the help. I had another question regarding my rebuild and as soon as it comes to mind I'll post in this thread.

MXjunkie926

Finally came to me. I have a set of test pipes to run on the car for ***** and giggles and want to have the car tuned to run on these. Is there any way to flash the factory ECU to run on the test pipes with high heat racing O2 sensors? Or do I need a standalone/piggyback system to accomplish this task?

terrasmak

iTrader: (8)

Install test pipes , drive car.

Best results, get it tuned with Uprev when your mods are complete.

MXjunkie926

Good to know...thanks a bunch. The info I've received on here in such a short time has helped sooo much it's unreal. You guys rock like tube socks in a 70's porno!