Z31 engine swaps

miata1.6 · 01-06-2006, 12:21 AM

OK, so i was sitting here thinking about the car of my dreams and the Z31 is it. IMO it is one of the best looking cars out. But the performance is well, not that great. I want to get a 240SX and turbo it, but later on in life when i have a place of my own, out of colledge, and a steady job, i want a car to seriously make spectacular, a Z31. So heres the question, what are some engine swaps that are not like an extreme thing to do. How about a turbo KA swap. I want your opinions, and i would never go bigger than a V6.

DeleriousZ · 01-06-2006, 12:36 AM

swapping in any 4 cylinder engine into the z31 would be shooting yourself in the foot with a rocket launcher.

for high performance there is nothing more than a vg30et needed... rebuild the internals with z32 rods and forged pistons, and do some headwork and the engine is good to 600+hp, now that's with supporting mods of course...

and as for the 'performance is not that great' you've obviously never ridden in one that's got <$1000 worth of mods in it (exhaust intake and boost controller)... on a cool day with good high octane gas it can rival the acceleration of a 350z...

if you absolutely must swap an engine, look into the rb series... the rb20det would be the easiest seeing as they came stock in the 200zr in japan, would only require a front clip or some custom mounting and so on.... next up is the rb25det or 26dett, both will require quite and extensive amount of fabrication and custom work and isn't really worth it unless you're going for the show car or unique(and extremely expensive) look

if you're that much into 4 bangers, i'd stay with the lighter 240sx/sylvia chassis.

xXxRocker5150 · 01-06-2006, 12:54 AM

don't forget a vg33et swap (I think that's the engine)... 10% more displacement right
???

DeleriousZ · 01-06-2006, 12:56 AM

yeah that's true, from a pathfinder... need to replace a bunch of stuff if you want it to run well turbocharged (cams mostly) and there would need to be something done about the intake manifold (or lower the engine down with some poly mounts) but yes, fully built it would be the better engine

stephenp · 01-06-2006, 11:45 AM

so how much work is it to swap the z323 internals in????
just swap or custom ground????
also what about connecting rod and piston seat hight is there a maching required to top of pistons tom not extrude from the top of the block???
if not its of to ebay i go (lol)

xXxRocker5150 · 01-06-2006, 05:06 PM

well the engine I'm thinking of was offered in the fairlady z31's ... I thought it was the vg33e but I could be wrong...

DeleriousZ · 01-06-2006, 07:16 PM

i believe the z32 rods are a direct bolt on if you use the z32 pistons... i think they work with the 87-89 pistons as well, but running the 84-86 engines you'd have to change a few things... can't remember what it is, but the ring lands on the stock pistons start to shatter at around 450hp, and the z32's pistons are good to around 500rwhp before they start breaking, so going with some nice forged pistons on top of the z32 rods will net you a 700+ rwhp setup..

i don't believe there was any vg bigger than 3 litre offered in japan... i know there was a vg20e/t offered there, and the rb series rb20det, but i don't think there was ever a vg33 that came stock in a 300zx

xXxRocker5150 · 01-06-2006, 10:10 PM

well in the turbo FAQ at z31.com they say that if you can, get a vg33et engine from Japan becuase it has like 10% more displacement...

DeleriousZ · 01-07-2006, 01:31 AM

" If you're going to build an engine, do it right. Start with a vg33 to get the extra 10% displacement over a vg30 and you'll have 10% more power for free! Good pistons to lower the 9:1 vg33 compression ratio and good cams to replace the low-speed cam grind used in trucks and you've got a pretty good engine. Rebello, Sunbelt, and Malvern racing all build wonderfull Nissan engines, expect to pay around $5k for a basic high-quality reliable streetable engine."

from the 'new' turbo faq

xXxRocker5150 · 01-08-2006, 12:00 PM

^that's the one I was thinking of... I thought it was offered in Japan... meh I guess not, thanks for the clear up

MikeMan · 01-10-2006, 02:42 AM

Drop a VG30DE in, and start working on that. A more efficient engine will respond much better to mods later on than the SOHC VG.
The VG30DE already makes 20+hp more than the stock VG30ET. The twin turbo makes 100hp more. Its clear to see which engine is going to respond much better to modifications.

Grab the VG30DE, get some forged pistons and some big turbos (or a supercharger) and you've now got a car that will beat 99% of cars on the road, and not look like a lame family car.

Jaymes · 01-10-2006, 03:50 AM

^ so you're saying that turboing the vg30de would be cheaper than swapping in a vg30dett?

MikeMan · 01-10-2006, 05:07 AM

Quote:

Originally Posted by Jaymes

^ so you're saying that turboing the vg30de would be cheaper than swapping in a vg30dett?

Depends on if you're going to be replacing the pistons and turbos anyway.
Swapping in the vg30dett and replacing the components that make it the vg30dett is rather pointless, time consuming and expensive.

xXxRocker5150 · 01-10-2006, 05:59 PM

^ IDK man, with a stock turbo engine and about 1,000 worth of parts, your practically in TT range... if you spend about 2-3000 bucks with turbo, fuel management, and other misc upgrades you'll be whooping plenty of cars. If you swap in a VG30DE and than turbo that could cost just as much if not more, and be alot more time consuming... just my 2 cents

DeleriousZ · 01-10-2006, 07:07 PM

hush mikey, it would be a bitch to fit and much more expensive overall... would only be worth it imo if you were going for a unique look or major hp.... even then you could always go for the rb26, mind you that'd be a bit more expensive and labour intensive...

bottom line is the vg30(or 33)et is about the best engine you can have in there power to money wise, aside from maybe one of those lame ass v8's...

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