Does anyone know what the rear end on the 350z is good for? I've heard that the axles need to be upgraded when exceeding hp levels of 5-600, does anyone have any follow up on this? Also, is the stock pumpkin good for same levels with installing a diff? Any info is appreciated, thx

 

the rear diff is strong for 1000+ hp. Not many, if any, cases of a diff failure have happened due to power. I'm sure due to the nature of a wear item some people have worn them out but i would guess mostly the road racing guys. Adding an aftermarket diff is usually traction reasons in road race and not due to the strength.

stock axles are weak but at the same time quite a few people break the dss pro axles as well. I'm at 652 hp on stock axles but i don't do any high rpm clutch drops which would damage the axles. Just have to be smart about it and run a soft sidewall tire to absorb the impact. Personally i couldn't justify 2400$ axles when they break also. Turn around time to get them fixed is a little slow as well so i'd rather break a 100$ axle and replace it with a cheap backup i have in the garage than tear my car down and wait 2 weeks to get the fixed ones back from DSS.

 

i wouldnt bother with the axles as well...

 

So when going past 500+ what else needs to be replaced/upgraded besides the usuall bottom end and clutch? What are the oem heads good for? Looking at building mine soon or just buying a stage 1 or 2 short block and seeing what i can push out of my setup.

 

im on stock heads and cams with bc springs and retainers(was supposed to do cams but then needed to get the car back togeather before they even got in the states) and made 600 ft lbs of torque and 587hp through a slipping clutch. so the heads and cams will flow plenty if it held that(which the turbo should easily in my case especially since i never hit peak boost it makes 600 ft lbs at 26 psi and slips so never hit my 32 psi i have the boost control set at.) it would have been over 650 hp. i wouldnt look into headwork personally unless shooting for over 700, and same for cams if you run a billet compressor wheel.

the billets work better at higher pressure, lower pressures they flow the same as cast so while you make more power at less boost those turbos need more boost to max what they can make.

 

you can make 500-600 on bone stock heads but at least upgrade the springs if you've got it apart.

 

Looking at building mine soon or just buying a stage 1 or 2 short block and seeing what i can push out of my setup

 

Is there a F'ing echo in here?

 

How necessary are upgraded head studs? I was told i should run ARP extreme duty for around $420. Are these needed for 550whp?

 

Are you taking your head off for any reason? Since you can't re-use the stock bolts, ARP's are pretty much a given if you are doing head work.

 

I am not an engine builder by any means, but I think you have to take the heads off of any block if im getting or building a short block. I was unaware you cant reuse the oem ones.

 

Not to be a douche or anything, but all of the answers to these questions have been discussed multiple times. There is even a thread dedicated to it all.

 

Lol. I was waiting for that. Sorry guys, I tried searching but when searching for "head studs" or "power limits", there are hundreds of threads that pop up. Maybe I just wasnt sure what to type in.

Do you have the link to that main thread?

 

Rear diff is unbreakable so far. However I have broken a few axles and ripped the diff off the car twice.

 

Start here. Will answer some of these questions. Read the threads that come up. Just browse the Forced Induction section for pages. A lot of good info in there.

 

dude is looking to snap axles!


ahahahahahahahahahahahaha

 

652hp, stock axles.

even dss pro axles break. they are free replacement but it takes 2 weeks turn around so total time probably 3 weeks from removing them and shipping. I'll go with the 150$ a set of stock axles. Just don't be a jackass and drop the clutch at 5k and you will be fine. I launch around 3500 and slip the clutch. If you are going to a track use bias ply tires and they will absorb the impact way better than radials.

 

What failed for the diff come loose?


I just saw that this was an old thread, disregard.

Thanks,
Bart