How much power can the Z31 motor hold safely?
 

I'm about to take over my dad's 86 NA, since he doesn't drive it. Someone on Zcar.com told me the blocks and heads are the same between turno and NA, just the actual pistons are different. So if I were to go with an OE rebuild...no fancy pistons, no aftermarket rods...maybe just aftermarket cams....how much hp will the bottom end take? I know the 280ZX turbo motor can safely hold 300hp, even more, if you take precautions as to detonation. Also where is a good place to buy a set of nice pistons and rings for the Z31?

The VG30E is a solid motor. The stock internals can handle in the ballpark of 400hp at the crank. The hard part is getting there and being able to put it to the ground. What do you plan on doing?

91zxtt is right.

I would post this on www.z31.com many gurus there could answer this most acuratly. Not that your not right 91zxtt just makin a suggestion :)

I agree with everyone else here -- the VG30 is a solid motor, but getting into the high (250+) hp range is at best difficult. You can start with the following mods first which are described in detail at Z31.com:

better cat back exhaust
240sx throttle body (SOHC, w/ cruise)
headers
cams (see z31.com for types)
:hpydance:

To answer your question 91ZXTT...it's not really going to be a daily driver. Just a sort of weekend car I take out at night for a nice cruise, or take out in the summer because of the ttops. It will also be a secondary weekend car as I am also building a bad ass 1977 280Z turbo with forged JE pistons and the works. I just want a Z31 turbo also, well because I'm a guy and I can have two fast sports cars if I want :)

If the stock crank (being the weak link I assume) can hold 400hp, that's more than what I want to hit. I just wanna hit like 325 or so max. Maybe 15 psi being all I'd run, but usually less. Now one question was answered, as far as the motor being super tough and how much power it'd handle...now, where can I find a good set of pistons for it? Vicky Brit has a set of them, std, and 2 overbore sizes. I'd probably want to go with the .5mm overbore, because bigger is better lol Anyone have anything to say about the piston sets Vicky Brit sells? MSA has some, only in std bore though for $60.07. Is that going to be for a set of 6 ya think, or just one piston with rings and clips?

I think thats $60 for 1 piston, maybe wrong though.

$60 seems like an awful lot for a dang piston. At that price, I might as well add a little extra on and just get a BRC forged one and not have to worry about it.

Think anyone could hook me up with the right specs, so it'll fit the Z31 heads (not 4 valve relief like on twin turbo pistons) correctly, but still work with the forged Z32 stock rods?

Yep, knowing VC, that would be one piston. Nissanparts.cc sells OEM turbo pistons for 48. each. Good call on the upgrade. If you're going to the trouble of rebuilding might as well use better parts. The people at BRC should be able to tell you what's good. Other z31 owners have bought pistons there. Ask them if they still have the specs from one of those orders, Spencer England's order for example. He bought BRC pistons for an 86 turbo. I think the price was around 450.

You'll find that performance parts are often less expensive than the OEM parts.

once you get your motor rebuilt to handle boost, get the usual Intake, exhaust, 240tb, pathy intake manifold, boost controller, z32 fuel pump, injectors, IC, turn the boost to 12 psi and rock out. oh yeah also get a reflashed ecu JWT:) i believe that should get you to your hp lvl desired. :doh:
Also an electric fan and larger nicer radiator would be good supporting mods too