View Full Version : 300zx z31 engine swap easiest way to turbo?

09-01-2009, 04:57 PM
hi there i have just recently brought a 300zx z31 shape 3.0 normally aspriated, however i'd like it to have a turbo engine as i love the look of the car its black with black rota wheels and targa top i just want more power now so i can upset these newer cars on the road and it'd sound awesome with some wastgate chatter coming from such a cool looking car.

i thought of rb25 however i've been told the supra twin turbo engine is an option i'd like to know if there is anywhere i can get the mount kits easily and then i'll search for a engine to suit which ever mounting kit i can obtain easily then i should have the swap done and the car on the road by the summer ready for some car shows.

any help even pointing in the right direction would be appreciated if there is such a thing as a turbo or supercharger conversion for the normal engine that would also be considered.


09-01-2009, 05:18 PM
I seem to remember a Vortech belt driven supercharger designed specifically for the Z31 3 litre :) That was a few years back but worth a look. Warning,,it was NOT cheap but did include everything needed for a turnkey changeover. The Vortech units are kinda unique in the fact that they are actually half a turbo, with the exhaust drive replaced by a belt drive and planetary gears, as opposed to the roots type SC found on drag cars etc . As Im originally from Canada ive used them on large displacement V8's with startling results :eek: I would think they would work well on the 3 litre but no experience there :D

09-01-2009, 08:59 PM
You could always just go with the turbo version of the engine you have got. There are little differences. The only thing you would have to do is change the passenger side engine mount to allow room for the turbo. I did this on an old car a few years back and it worked fine. As for the actual engine itself you would obviously need the corresponding ECU, and passenger side exhaust manifold. I don't know what internal parts of the engine (i.e. cylinders, valves etc) that differ but I may be correct in saying they are the same. Earlier engines ran with Garret T3 turbos, and some later ones moved to the T28, but you can imagine the possibilities with a T3/T4 hybrid could do, but you would have to do some work to cope with the extra boost, though they can handle about 10 P.S.I. with little problems giving about 300 BHP. Any more than this power you would have to get the ECU changed/re-programmed. There are a few people on here that have gone to town and are pushing stupid power from the original lump, its all a matter of how far you want to go.

10-01-2009, 12:55 PM
what he said & add large intercooler allows 14-15 psi which is all the t3 will give lightweight flywheel etc has given me best 13.7 quarter mile

10-01-2009, 05:50 PM
oh yeah .. add an intercooler. Even the turbo models didn't come with them. Its what I will be doing to mine. The Sierra Cosworth intercooler is very compact and very efficient, though some people install the Honda Accord version.

10-01-2009, 05:55 PM
Keep it Jap!

10-01-2009, 06:12 PM
I have for sale a 1985 300ZX turbo engine complete with turbo, exhausts manifolds and ECU, also Nissan front section exhaust pipe and stainless steel middle and rear sections.

10-01-2009, 08:18 PM
What they said + you could turbo the NA motor as it's not really that high compression 9.0:1, just fit an intercooler.

I'm currently building a 9.0:1 motor to turbo as they have better off boost torque.

10-01-2009, 10:06 PM
i have had a few z31's turbo and n/a,i would like one again one day because i like the shape of the z31,but nextime,i will save myself loads of time and trouble by fitting a 383ci small block,last time i played around with a 400ci i had a touch over 300 bhp,i put it in a nissan patrol,the 383 is a little newer and has as standard more power than the standard 400,

so keep your'e eyes peeled for when i get a z31 again,i did think about doing it to my z32,but stupid that i was i whent and bought a replacement engine when the old one died in the drive,i should have listned to my wife and stuffed the chevy in it,but at the time i thought i would keep it standard.
ive done the turbo,s thing on many turbo things iv'e owned,i like hastle free no subs for cc's tho it,s not always the fastest,but the sound is the best.
converting a z31 to turbo is more hasstle than it's worth,not just enegine bits to swap,and it,s not just a complete vg30 out and vg30t in either,crossmember,turbo gearbox,,,,,,,,,get a z31 turbo car to start with.

this wont help you much,but it will get you thinking,unless you like the pppsssshhhh! sound.

10-01-2009, 10:41 PM
Converting a Z31 NA to Turbo isn't more hassle than it's worth, I did it. besides Turbo Z31s are few and far between in the UK (so are NA's for that matter).

11-01-2009, 10:36 AM
i assume the gearbox is a manual already, If so it should just go straight on any VG30ET engine. The crossmember doesn't have to be changed at all. All you need to do is drill out the spot welds on the passenger side engine mount and replace it with one off a turbo, 30 mins at the most. Replace the passenger side exhaust manifold with one from a turbo and bolt your turbo onto that. Then you will have to put on the Turbo to throttle pipe to that of a turbo model. In fact if you have all the parts at hand you could probably do it in a weekend. After that its just peripherals like intercooler. I think I am right in saying that the gearbox was common between the N/A and turbo models.

11-01-2009, 12:56 PM
I think I am right in saying that the gearbox was common between the N/A and turbo models.

Unfortunately not:

All NA use FS5W71C
Turbo to 02/87 use FS5R90A T5
Turbo from 02/87 (facelift models) use FS5R30A

(N.B. this is for the U.K. market models - JDM VG30T as for UK, but VG20T and RB20T used the FS5W71C. Facelift occurs a few months earlier in 10/86. USA pretty much the same as UK - T5 to 09/86, 30A after on turbo).

11-01-2009, 02:33 PM
oops ... I stand corrected

Cheers Mr. F :D

11-01-2009, 03:12 PM
I also have the T5 gearbox for sale.