Hey all,
I've got myself an '88 Z31 NA. It's nearing 260K miles on the clock. The transmission will need some rebuilding, and rather than overhaul the car, I was thinking of breathing some life into it. I like the car a lot, and want to make some changes while keeping it fairly stock looking. I've been pondering motors and which one would work best for me. A VG33 would be the easiest, as from what I heard it's almost a direct replacement. A VG30DETT looks like a lot of work, but I've wanted to see what it would be like if I went a different route, perhaps with a few more cubes, like putting an 8 in there. I know the VH45 will fit, as I've measured one up, but that would also mean changing to an auto transmission, if I were to use the transmission that goes with that motor. Then there's the back end to consider. Is it necessary to use the Q45 differential as well, or can I use a Z32 diff with a Z32 sub frame (if I can fit a Z32 subframe in there)? There's also custom mounts to think about. I might have to visit a junk yard with a tape measure.

I've always got lots of questions but that's just me

If there's any Z members out there who've done work like this, or know of some who have, would you let me know.

Thanks,
Dave

[Edited on 10/22/2005 by Ford_Falcon]

Hello... regardless of what swap you do it's gonna take alot of work and parts! Consider that you will need not only the appropiate MyISAM and tranny... but harness and ECU also.

I think the VG33 is a direct drop in, right?

I know a guy who is dropping a VG30DE (from an NA Z32) in his Z31 and he is having a hell of a time but it's coming along nicely. A VG30DETT would be pure hell me-thinks since you would need to have custom faricated intercooler piping and what not!

Have you thought of the RB series of motors? An RB20DET, RB25DET, or the infamous RB26DETT would be killer and it has been done.

Pretty much it's like this: IF YOU GOT THE MONEY... SWAP CHOICES ARE INFINITE!

As far as the rear Q45 and Z32 diff... I think they are the same. But don't hold me to that....

Hello, I was wondering how much power you were thinking of making.

If you want to do a simple swap the vg33 is a easy swap. Another easy way to get power is turboing your car. That will be the least expensive way to get power.

Its all on how much money you have and how much power you want to make.

As for the rear it depends on how much power your making cause the 3:70 LSD rear end from the turbo Z31 can handle about 350-400 HP.

VG33 comes out of the older Frontier?

Thanks for the replies.
Yes, the VG33 from what I've learnt is almost a direct replacement. The motor was used in the Frontier, Quest, and Pathfinder into the late 90s.

I have thought about just swapping my NA for a turbo, but I like a challenge, and I've always wondered how it would perform with an 8 in there instead. I don't have the funds yet as I'm waiting for a re-fi before I put a little towards my toy, but I'm making sure I know what parts and where to get them before then.

An RB25 or 26 in there would be quite an adrenalin rush, and there are pictures online of people who've done it, but they're expensive to buy, and most places I've seen that sell them don't supply the ecu or harness.

A '93-'95 VH45 from an Infiniti Q45 is a choice motor from the VH range because it had the variable valve timing, and they're less expensive than the RBs, but they all had auto transmissions...hence one of the issues to overcome. However there is a company out there that have mated a VH45 to a Z32 and fabricated some sort of adapter plate to connect them. Not sure what exactly was done, but I'm trying to find out where they're located.

I've not worked out a figure on how much HP I want it to produce. My main concern is getting it all to work together smoothly. But I do want a strong transmission and differential for it, regardess.

The weight issue is another thing. I want the car to still be somewhat well balanced, and since the VH is an aluminum block, that might be what I'm after.

Unless you have a hair up your ass for a z32 MyISAM, or v8 don't bother. You can get plenty of power out of a bored vg30 or vg33. You can use a z31 88-89 Turbo tranny if you want a solid tranny, its basically the same internals as the z32 tranny. Like I said, if you want to swap in a z32 or v8 MyISAM, go ahead, just saying you can get a quick car with a built vg30 MyISAM if you want. Quite a few are running low to high 11s.

Lastly, I disagree with 1wildzer, the rear end can handle well over 400hp, there are stock LSD diffs doing 600hp at the wheels and MANY doing 420 - 520 at the wheels. Sure there are always exceptions to the rule, but most rears hold, but if you are concerned grab a diff out of 88ss.

Anyways, good luck with whatever you decied.