twin turbo motor in 85

[ericgb35]

can you put a newer twin turbo engine in a 1985 300zx if so what mods need to be done to do this

[k3smostwanted]

Originally Posted by ericgb35

can you put a newer twin turbo engine in a 1985 300zx if so what mods need to be done to do this

there is a guy on here now named "MikeMan" that is currently swapping a VG30DE into his Z31 chassis. according to him, the N/A motor barely fits and he had to have custom headers built to weave in and out of miscellaneous items. for details ask him about what kinds of parts, brackets, etc need to be made up.

i can tell you right now that if the N/A has problems fitting in, the turbos and piping will make the TT motor that much more snug against the engine bay walls. my advice would be to choose a different motor if you do not have alot of experience and the tools at your disposal.

the RB20DET can makes gobs of power with minor modification, not to mention it will be much cheaper to get a hold of a RB20DET front clip in comparison to a VG30DETT front clip. also, the RB20DET came stock in the Z31 chassis in Japan carrying the name 200ZR. so the motor should fit in with rather no to little modification.

[MikeMan]

G'day Eric, welcome to the forum.
As k3 has mentioned, I am currently doing a VG30DE swap into my z31 '85.
I've run into a few roadblocks that I wouldn't have had if i could ask someone about it, so please don't hesitate to ask me anything.
The main reason I chose the VG30DE over the DETT is mainly due to the TTs being far more expensive here, and because I planned to supercharge it later after a full teardown/rebuild anyway.

If you're serious about it, the VG30DETT will fit but its gonna be tight. The main issue that you're going to come across is that the VG30DE is wider at the heads (due to the 4 sets of camshafts) and its kinda hard to get your arms down the side of the engine. Turbos should fit no worries, but make sure you know a good exhaust fabricator, with their own mandrel bender. The exhaust manifolds have cost me the most out of the whole swap, simply because one side has to go around the steering linkage.

A few things to consider.
First and foremost, you'll have to get some custom engine and gearbox mounts made up. Get the transmission that suits the engine so you don't have to screw around with custom bellhousings etc. Its easiest to grab a front cut for this. Take the front cut around to a decent engine mechanic and get him to fab up some custom mounts and drop the engine in. This way you'll save yourself alot of headaches and trips to the engineer. Also, you don't need an engine hoist then.

Secondly, make sure you sort out the oil filter before you get the headers made up. You'll need a remote oil filter kit, as the stock bracket that comes out of the engine lies right where the headers (and possibly turbos) need to go. Chances are you'll have to get the engineer to make up an aluminium block that will bolt onto the side of the engine and run two hoses to somewhere else in the engine bay where you're going to put the filter. GET THIS 100% COMPLETE BEFORE YOU GET THE HEADERS MADE UP. It seems and looks so fucking simple but it's real fucking hard when you've got headers less than 10mm away from the block and you've got to fab up some rediculously shaped block of aluminium to get the oil out. I've been trying to get this sorted for the last 6 months now.

Another thing thats going to cost you alot (money or sanity) is the electrics. You'll need to wire up the new ECU to the engine and to the rest of the car. Not as simple as it sounds.

Other custom things you'll need made up is the tailshaft and the intake piping. The z31 gearbox uses a cable speedometer whereas the z32 gearbox uses electronic, so you'll probably have to try and swap the speedo units of your z31 dash and the z32 dash and calibrate it. I'm going to try and shoehorn the whole z32 instrument cluster in, but I'm probably going to have to get a custom dash made up though, because they're different shapes.

Other than that, you shouldn't run into anything major. Let me know if you have any questions, you can PM me or throw me an email at MikeMan[at]Nismo.org. My ICQ is 12065451. MSN is my email. Skype is blaqeagle

Good luck!

-Mike