Hey guys, will be grateful for any useful comments. The VG30E engine in my 1993 maxima may have recently suffered a slight case of overheating. There appears to be no major damage to cylinder head gasket and there's no steam at startup. However, am getting an intermittent rough idle (don't know if that vacuum leak issue but engine does not cut off) and performance seems to have fallen off. And there's that annoying ticking noice associated with engines of that vintage. If I decide to replace this engine rather than repair it, can I swap it a for a later engine without too much modifications (engine mount points, harness etc.)

Unfortunately, there aren't any engines that will swap "right in." Even the VE30DE, which came in the SE variant of your car, isn't a straightforward swap. There are a lot of electronics involved, among other things.

Thanks dude, guess I'll have to go the repair route as I really love the car's performance and am not quite ready to give up on the old dog

As for replacement you can use any VG30E from 88+ as a replacement. If you get one from anything other than a Maxima you just simply have to swap all of the external parts from the Maxima VG to the new VG. One VG to avoid is from the Nissan/Ford vans equipped with the VG as the internal setup is slightly different. They were setup to be non-interference, which changed power ratings a little bit (a little less if I remember correctly).

If you have to replace anything that costs more than a few hundred dollars I would just search for another VG in a salvage yard as they are very, very inexpensive.

noted and once again thanks. You guys are very helpful and I really appreciate the effort.

is it possible to swap a vg30et in there? like with little trouble? or is there tons of stuff to do. i'm planning to get a motor from the 300zx z31 and just drop it into my maxima.

The block and heads are the same between the two (1987+ Z31's, previous years aren't) so it can bolt in there but the turbo setup is a little more difficult to pull off. You'll either need a custom motor mount, slim fan shroud, or completely relocate the turbo to get it to fit. Because of this.... I would actually stay away from the VG30ET swap and just use what turbo components you can on the stock VG30E in your car. The compression ratio is only 9:1, which isn't too high for boost. It will get your more power all throughout the rev range, definitely has better low end, and can likely even get better fuel economy as higher compression ratio engines tend to get better economy.

From there its custom exhaust, intake, depending on how much power you're aiming for you'll have to upgrade the fuel system to at least the stock Z31 stuff to handle maybe around 250 hp or so safely. Anymore and you'll need to go with even larger injectors.

Computer tuning would also be required. You can go piggy back, stand alone, romulator (modified stock ecu that basically works like a stand alone), or an after market modified ecu (Jim Wolf Technology).

Its definitely not a drop in procedure and takes some work... but is oh so worth it in the end if you're willing to put the work into it.

One thing to be careful of is the transmission. Both the auto and manual are quite weak stock... they barely last with stock power. Once you start making more boosted power they would really need to be upgraded to keep them from breaking. The 5-speeds are a little more difficult to upgrade but one good option that helps a little bit is to swap to the 92-94 5-speed transmission. They're a tiny bit stronger than the earlier VG transmission but still aren't extremely strong.