Moved: Unsure which engine to use, asking for input/opinions

[30 ounce]

What is the displacement tax threshold?  You can get an aluminum 5.3 liter LS .  Or even a 4.8 liter LS but those would be iron blocks.  

[30 ounce]

I went with the LS swap mainly because of the weight.  A fully dressed LS1/T56 is only 30lbs (13.6kg) more than the stock 2.8 liter with the T5 trans and the weight is centered more because it’s the transmission that is actually heavier. And with the quality of Hoke Performance LS swap kits it looks and fits like a factory made V8.  The aluminum 5.3 can easily make 300hp at the wheels.  I don’t know how easy it is to get LS1 parts in Germany but here they are everywhere here and they are cheap!  I couldn’t get the power I have with a 1 or 2 JZ or RB without spending at least twice as much as I did.  

[seattlejester]

The S30 engine bay is quite a bit larger than an E30. I used to be able to stand inside the engine bay in front of my engine with my 7mgte. In my friend's E30 I think part of his accessory drive sits offset of the fan because they are so close.

 

If you are precluding an engine choice based on a removable-nonfunctinoal cover than I think aesthetics are a higher priority than performance. It seems maybe ease of install would be a close second over performance as well. Might be worth sitting down and thinking about what is the highest priority and making a list in order. An L28ET seems to be the easiest, aesthetically it is pretty much stock, it is dirt easy to install, and it can definitely make over 300hp. If that is not on the top of your list than you have another priority like wanting a swapped car, or street cred, etc. Hard for us to play the game without you giving us your list of priorities. You mention sound, aesthetics, hp, ease of swap, torque, turbo lag, insurance, tax, etc. Make a list in order of priority. If an engine is suggested that meets the criteria and you still don't like it than you definitely have a different priority order, adjust until it accurately reflects what you want.

 

To start for me my priority was:

Ease of install

 

So I went with an L28E that I converted to carbs. That was the easiest to do. 

 

Then it switched:

Turbo (preferably factory)

Cross flow head (preferably with intake on driver side)

Similar displacement or larger (I had a 2.8L in my 240z)

Ease of service (parts available in the parts store)

Low modification (keep factory mounts to make it reversible)

 

That precluded the RB's, SR's, german engines, etc, even the turbo JZ's. Basically left me with the 7mgte. That is what I did.

 

When the 7mgte let go, my priority shifted:

Ease of install

Turbo

R154 compatible

 

That meant either staying with a 7mgte or swapping to a 2jz, or going to a 4g63 with an adapter. Since I still wanted turbo, but I didn't want to have to rely on importing parts or dealing with a new platform, my priority switched with ease of finding parts taking over factory turbo charged so I went with 2jz-ge na-t.

 

Then I decided to swap in a stronger and smoother transmission, priorities were:

cheap

strong

not visible under from the side

 

So low modification fell off the list and cheap while not visible meant I had to do the work and spend a lot of time with getting the fitment right. 

 

At each point the priority changes, but looking back I know exactly why I picked each one. There really are no regrets as at the time it made justifiable sense, granted in hindsight I would have done some things different as options weren't available or affordable at the time.

 

Some things to consider:

 

Transmission:

Any engine with a decent horsepower output is going to use a bigger transmission. LS, JZ, RB, VQ. They all have fairly big transmissions especially for their strong transmission option. The VQ transmission is I believe the biggest next to the the T56, but the benefit is that all of those mentioned above actually can run the CD009 transmission as it is strong, cheap, and plentiful. You can cut down quite a bit on bulk using the newer adapter plates the require bell housing cutting but it still is large. Even at that large a size with an early Z 70-72, you can probably fit it without any drastic changes other then removing the mounts. The later years you have to remove the whole trans tunnel brace type situation. With that said the R154 from the JZ can fit with custom mounts on the factory points in the early years, I still have my "kit" if you want measurements.

 

Rear end:

You are planning on putting out more than double the power the axles are used to seeing if you want the earlier cars you are also going to have the weaker stub axles. That means you need to factor in stronger axles, rear end, etc etc. This can end up costing as much as the engine itself so keep that in mind.

 

[Zetsaz]

My priorities have almost been opposite direction lately. The more I drove my daily (a G37S), the more I realized that I didn't even take advantage of the top end of that car. I quickly realized that anything near 200whp in the S30 would match the power to weight ratio of the G37s.... sounds fun enough for me and easy enough to do with a very mild turbo L28, or some extensive work on the L28 with fuel injection. 

 

300hp is a common goal for a lot of people, and really you can hit it with almost any of the popular swaps. For your goals I really think the turbo L28 would be a solid option. It'll hit the numbers. fitment will be easy, will be lighter than a 2jz or an RB, turbo will let you adjust how much power you're making to meet regulations when you need to. 

[Max_S]

@30 ounce
There is no defined "threshold", as far as I know it's "fluid".
The bigger the displacement, the more expensive the taxes.
It's why a VR6-Golf is much more expensive than a 1.8T, because while they can put out the same power and can have the same equipment the VR has more displacement.
It's meant to discourage using big thirsty engines, unless it's for certified vintage cars (which my Z won't be).
Those who run LS-cars (or any American V8) usually just ship (parts for) them in from the US, either through the manufacturer or themselves (same goes for a lot of cars, by the way).

@seattlejester
Early on I read somewhere (don't remember where exactly) that a big downside of the 350Z's engine is "the big plastic intake, which can't really be skipped".
I've seen one swap throw an R35 GT-R's cover on there, but it was just a photo, I don't know if it even works.

Priorities:
Looks aren't the main priority, but they are still very "high up on the list" since I'll spend a lot more time looking at the car than looking out of it.
The original idea was to get a classic car, put in relatively modern technology, and throw around 260hp at the rear wheels (in Europe WHP is pretty much all that matters, almost nobody measures or mentions crank-hp).
My first car ever made 68hp, the MX5 makes 131, it just seemed "neat" to double that again with the next project.
And then that "little child in my head" went "why not make it 300, nice even number?"
So I guess that's where I went off-track a bit, partly my own fault, partly that of seeing all kinds of crazy engine swaps from the states.
And when I looked around the first thing that came up was the 2JZ, followed by LS-swaps.
I have to admit, a big part of the rotary-swap idea was the uniqueness of that combination, which is why I also went and put together a "plan b" with a piston-engine.
My main priority is to have "250+" horsepower at the wheels, and that in a useable way, meaning not just having power at the very end of the rev-band.
Great for the dyno and the 1/4-mile, but not very good for my kind of driving, where plenty of time is spent at as (relatively) low as 3-4k rpm.
The power is supposed to be actually usable for more than bragging.
Maybe I should tell, the first turbo-car I ever drove was the Opel Speedster Turbo, it had a whole lot of nothing coming from the engine, with the turbo kicking in rough and VERY late, I don't want that.
300hp is perfection/ideal, but I would probably be just fine if the car falls just short of it.
I guess number two is performance-feel (that was the problem-point with weight-distribution, in my mind a car wants to corner less happily the more weight I throw onto or past the front wheels), and also things like the engine being rev-happy and having a nice-shifting gearbox, no "pudding bag" or even automatic).
I've had quite a few people say "take any turbocharged engine, and just slap the biggest turbo on there you can find".
Yeah...no.
Might get my target-hp, or more, but as I said, I want a car with a usable power-range, so while a turbo is an option supercharging or NA-tuning is also.
Number three is looks, four is ease of install (I can get some custom mounts, I can't construct a pipe-frame to put the whole body on, I can expand the front of the tunnel a bit, I can't move the firewall entirely or create a new underside).
I'm not going to do a completely "tucked" engine bay (because that's impractical), and I might not get something super-mega-clean like the famous FuguZ, but it should still be nice to look at.
Summed up, with the hood closed it's supposed to look like a 240/260 that could be taken to the track, with a few updated details (seats, brakes, wheels, etc, but, for example, no rocket-bunny-stuff or huge wing), with the hood open I don't want carbs but also don't want a whole lot of plastic or a chaotic snake-pit of wires and hoses.
That look is also where my plan for a cage comes in, serving "tripple-duty".
1st, a cage improves safety, even a roadcar can go shiny side down.
Second, it improves stiffness, which is good for handling and for the approval-process.
Third, I think it would look good.
Parts-availability is low on the list, I don't care if a part takes two weeks from the states or Japan, as long as I can get the parts to keep the engine/drivetrain running.
A big bonus if the engine came with a five or six-speed manual, eases approval for road-use.
Fuel-consumption doesn't matter, as long as it is fuel (and not diesel, I've had someone recommend a cummins-swap), I plan on a fuel-cell (goes for the racecar-style) so I should be able to haul some fuel if necessary.
Cost isn't really on the "priority-list", I don't want to waste money but also not cut corners or safe a tiny bit of money but be unhappy with the result.

Limitations:
Fuel injection, 6 cylinders (decided I don't really want a 4-banger after all), 3 (3.5 at most) liters of displacement in stock form (the TÜV doesn't see if the displacement was enlarged as part of tuning), ideally an engine I can run on a custom ECU (haltech, motech, that sort of thing, so I have more freedom in programming (with safety-measures, for example, or a low-power-lean-run "TÜV"-setting, that sort of thing).
Also, some space left in the engine-bay to run power brakes, sufficient (or over-build) cooling, an A/C-system (on the engine or electrical), because I need heating by law so I already got to have the vents and such, and maybe a power steering kit.
Oh, and the whole package has to fit a stock hood, if I get an intake sticking out the hood, or even just a scoop, chances at road-legal approval go down DRASTICALLY (pedestrian safety is seen as compromised with anything bulging/sticking out of the hood).

Gearboxes:
Manual, five or six-speed, no straight-cut gears (it's still a roadcar, and the straight-cut-gear-whine gets on my nerve even if I only watch videos).
Nice if it fits with just a "massaged"/widened tunnel, even better if it fits (towards the interior) with the stock center console.
Big bonus if I can use the donor car's gearbox (stock or if necessary with stronger gears), makes the approval-process A LOT cheaper.
Fabricating new mounts/having someone fabricate them is perfectly okay.

Drivetrain:
I'm already factoring in a new driveshaft, so if I find a place that'll make those I should be able to find a source for stronger axles if needed.
New/stronger differential is already on the list too, definitive decision there depends on the engine/gearbox I end up choosing.

Max

Edited September 21, 2018 by Max_S

[seattlejester]

Not anything really plastic there? The stock intake pipe is plastic as is for almost all cars. Manifold or collector plenum is big cast aluminum unit I believe, which has short comings in distribution so it usually gets replaced.

 

I've seen people mention this a few times. It really doesn't need mentioning. Who wants a peaky 300hp build? Like who takes an 2jzgte, 1jzgte, rb25det, or even an L28et which all have pretty flat-ish power bands and curves and almost make 300hp, and finds a turbo that doesn't spool until super late and then chokes the crap out of it up top so it limits itself to only 300hp? That is running a massive hotside and then basically an equivalent massive wastegate to open the moment it starts to spool. It really does not merit mentioning. That was a thing when turbo manufacturers didn't make anything for gas cars, now they do. Borg warner, precision, garrett, they all have a performance gas engine division now, so no more borrowing diesel turbos and dealing with their characteristics.

 

I am pedantic so a correction. Unique means singular. If it has been done and done more than once, then by definition no longer unique. I mean if you want a unique car, find the excrement of two singularly unique animals and smear it all over your car, it will be by definition unique, with an minute chance of replication. I went to a junkyard last week, and the guy there said he put together a 4 rotor 280z like a decade ago. 2x12A motors with a custom e-shaft. I thought there was only 1 4-rotor S30, even that is not the case.

 

A caged car really shouldn't be on the road anymore. A minor accident can go from a fender bender to a skull fracture. Sheet metal is a lot more forgiving than DOM tube in a collision. Roll bar with anti-intrusion bars may be sufficient for protection. You can get a cage and have it fit really tight to the body and run impact absorption material, but that would be pretty expensive and still it would take quite a bit of visibility away. I can't really speak on this with authority so I'll let others chime in. 

 

Make a list. We'll throw out options and test it:

 

Priority:

"Uniqueness" (super vague, maybe something like not-domestic or german, might be more apt a description)

"Aesthetics" (in regards to an engine is kind of tough, you have to narrow this down more, you mention not having hoses/wires everywhere, well turbo cars are going to generally have more hoses than NA cars etc)

300hp

no 4 cylinder

"Useable" power band

No transmission tunnel modification

 

Regarding your build, how much do you have budgeted for this? 

 

If this in any way feels harsh, here is where I come from. I had a roll bar which I removed it for a couple more inches of leg room. I had a fuel cell which I am replacing with a OEM tank from a camaro because I get fuel starvation on corners. I built my fuel system twice as I went from simple carb only to fuel injected turbo. Plan things out, if your plan can with stand scrutiny then it will be easier to justify going down the road. If someone told me 8 years ago that I would have over $30k in my $500 car, I probably would have reconsidered or done things differently. 

[Miles]

 

[Miles]

And then there is Darious

 

 

[Miles]

More Darious

 

 

[Gollum]

It's amazing what a powerband can look like when you max out a turbo with more than half your rev range left to go...

 

 

[Gollum]

If I'm honest, I think you should go with the VQ. A VQ35DE out of a 350z would be just fine and fit most of your priorities well. There's also the VQ25DET but they can be a bit hard to find.

 

With how far back you can get the VQ to sit (especially with a forward facing intake) clearing the steering isn't an issue. There's also prefabbed cradles on the market ready to weld in. It's a well established swap at this point, so little custom fabrication if that's your jam.

[Max_S]

@seattlejester First off, to you and all others who have replied here, thanks for the patience with the newbie 🙇‍♂️
The intake on the picture you posted is metal, and looks just fine.
However, when I googled VQ engines/swaps, I mostly found pictures like this.
And that was a bit too much plastic for my taste.
I've seen a few of the metal ones you posted, and two swaps running intake-manifolds from the GT-R, but when I went down that path I pretty soon found an adaptor-kit for that manifold for over 1000 Dollars.
So that didn't seem sensible, spending 1000 Dollars to swap one piece of plastic for a slightly prettier one.

Unique...yeah, bad choice of words.
"Rare" would have been better.
It would just be nice to have something that gets more of a yawned "seen it before" out of other people.
Doesn't have to be literally unique, but also not 1000000x done-to-death (like BBS on a Golf).

As for the cage, I assume you think I mean something like this:


I don't.
That's far too extreme for a roadcar (and probably a pain to climb through).
I was thinking of a half-cage behind the seats (like those Porsche sticks in their GT3/GT2 road cars), and maybe a bar to the front for some side-protection.
I had a halo-bar in mind for the added safety, but actually backed off that plan since I'm not really planning to run a butt-naked interior (and don't know if I want to cut the dash to bits).
So it's probably going to be closer to this than to this.

The List:

"Uniqueness"/Rarity=It's not going to be a showcar as the main purpose, but if it sticks out a bit/draws attention, that would be great.

So I don't want something that's been done a million times and turned usual business/boring.
As for aesthetics:
A clean engine bay, in my eyes, would be something in this direction:

A "messy" one something like this:


As I said before, it doesn't have to be completely "tucked", but decently organised.
That fuel-injection means a bit more electrics than carbs is clear, that a turbo means more piping too, I was just looking for good examples here.

The horsepower, as said before, would be nice, but I could be just fine with falling just short of it.
260 is the "must have", 300 would be the perfection.
The power-band, seems like I'm just not "up to date" on turbochargers there.
I know a turbo always has a bit of lag, I'm basically looking for a "compromise" so I got some midrange power, not just when I'm starting to scrape on the limiter.
Trans-tunnel modification/replacement...well, I'd like to keep the stock console, and it of course cuts down on fabrication if I don't have to engineer and construct a new floorpan.
Some widening/raising shouldn't be a big problem though.

Budget at the start (about a year from now) will be around 8-10 thousand Euros (9-11 thousand US-Dollars), if that money is spent I'll go "bit by bit".
As I said before, I got tons of patience, but not endless funds.
I haven't calculated out every Euro yet, but lets say I want to keep it "grounded", I'm not planning a 50k or 80k or even more money build.
Just like you can resto-mod a Mustang and stick 30.000 into it or 130.000.
At some point you got to decide where to put your money.
That's what I meant earlier with looking for a reasonable package, and it's why, for example, I kicked the RB26DETT early on since it would've been much more expensive for me than a 2JZ, which is relatively similar.
My MX5-restoration started out at 3000 Euros, by now it's at 8 grand.
Wasn't expected, but I spent money where it was worth spending, and if I had to wait for a month or two in between, I did that.


 

10 hours ago, Gollum said:

If I'm honest, I think you should go with the VQ. A VQ35DE out of a 350z would be just fine and fit most of your priorities well

It looks more and more like that (I'm still running two plans parallel, so this is talking piston-engines).
They're available, spares can be had at any German Nissan-dealership (even if it says "Infinity" on the engine, as far as I know), they're quite compact, and the heavy bit (the transmission) is relatively centered in the car (while the shifter doesn't seem to move too much).
And they put out enough power.
A problem I've run into is where to find engines in general, the (tiny) German market seems a bit expensive to me.
Or is it perfeclty fine, for example, for a VQ35DE (221kw version) to run at 5.500 Dollars (and more) used (from a company) with around 60.000 miles on the clock?
(Just the engine, no accessories).
Looking at engines I've found ones with shipping to Germany for as little as 200 Dollars, so if they're cheaper there that would be an option.
Or is there a good source in Japan (other than Nissan/Mazda/etc itself)?


Max

[Miles]

You seem to have several conflicting design approaches in mind. 

 

Asking for opinions will net you as many opinions as there are HybridZ members.

 

Suggest you research HybridZ and Google for German Z car builds (many).  This will help you scope the project according to German market, regulations, part availability and etc. 

 

 

In the end your project will be defined by:

 

• Local regulations
• Budget
• Skill level
• Project plan  (suggest a "Build spread sheet"  listing all costs and part numbers broken down by system such as engine, drive train, suspension,  brakes etc)

 

 

 

Edited September 23, 2018 by Miles

[Miles]

Roll bar/cage etc

That's far too extreme for a roadcar (and probably a pain to climb through).
I was thinking of a half-cage behind the seats (like those Porsche sticks in their GT3/GT2 road cars), and maybe a bar to the front for some side-protection.
I had a halo-bar in mind for the added safety, but actually backed off that plan since I'm not really planning to run a butt-naked interior (and don't know if I want to cut the dash to bits).
So it's probably going to be closer to this than to this.

 

Just something to hit your head on in a street car.  Or you can wear a helmet on the street.

[Miles]

Street rods in Germany.

 

 

 

 

 

 

 

 

[Gollum]

Both of the first two pics you posted are the same all aluminum intake as what the 350z had. They just also have the plastic vanity cover that makes an engine not look like a "mess" to non-car folk.

 

If you keep an L engine then EFI doesn't mean the engine bay can't be clean. To the contrary I'd say it's easier to maintain a clean look with EFI, but you certainly need to ditch a lot of the OEM design to it. I have ZERO focus on aesthetics with my car and it looks world's cleaner than that 280zx engine bay you posted.

 

 

[TUME]

Seems like you have same sort of plans with Z that i have. Fast and reliable weekend/holiday car. 

I went to SR20DET mainly because of weight and weight distribution.

If i would think now, i would also consider VQ30DET(T). With two small and easy spooling turbos it might be great engine. 

Of course it has to be JDM rwd engine and needs some custom fabrication. Intake is as silly as VQ35, but these engines are quite cheap.

Edited September 23, 2018 by TUME

[Max_S]

4 hours ago, TUME said:

Seems like you have same sort of plans with Z that i have. Fast and reliable weekend/holiday car. 

I went to SR20DET mainly because of weight and weight distribution.

If i would think now, i would also consider VQ30DET(T). With two small and easy spooling turbos it might be great engine. 

Of course it has to be JDM rwd engine and needs some custom fabrication. Intake is as silly as VQ35, but these engines are quite cheap.

VQ seems to be a decent option, Rotary is still my favorite (I have to finish calculating that one, though).
V6 with two "snails" on there sounds pretty perfect, but also pretty illegal ☹️
I have to see what the TÜV says to my plans.
There are the "power steps" in approval of 20 and 40 percent, above that and I have to see which requirements my TÜV comes up with.
SR20 still sounds nice, but I'm pretty sure I'll go with a six-banger (I already got a fun four-cylinder from Japan), so don't make me reconsider for the ten-thousandth time^^.
Or maybe I'll have two Zs one day.... 🤔
As I mentioned above, a big question mark is still a source for engines, the German market for Japanese engines is tiny and expensive, and searching craigslist state-by-state is pretty time-consuming.

Max

[seattlejester]

The metal manifolds came stock on the earlier years. They make other options too, but it seems like the engines with the dual intakes seem like the later years that have a plastic intake like most newer cars have like the ford ST's the LS engine, WRX cars, etc. They still feature the vanity cover which is removable. If that removable vanity cover keeps you from wanting a viable engine option then it is pretty much at the top of your list there on priorities. Nothing wrong with that, it is just an exclusion requirement for you that we have to factor in.

 

So priority for you:

No vanity cover, even removable ones

No plastic intake manifolds

 

No LS engines

No RB's

No 2jz's

 

Kind of reduces your options a bit.

 

Breaking the "mold" is fine, you just have to be aware that the more you break the mold, the better your skills will have to be as there will be less people who have gone down that route. Your reasons for breaking the mold though have to be really on point at least for you, just because you want some stranger to say "oh I have not seen that before" is not really going to outweigh being broken down on the side of the road because you need a custom serpentine belt that takes 3 days to ship. If it does outweigh it for you then more power to you, that "wow factor" is higher on your list of priorities than serviceability. Keep in mind with the internet, there aren't that many surprises left for those who know how to use google. 

 

Not having a halo bar would make this more of a roll bar than a roll cage. You will find terminology is pretty important here. I did remove my door bar after about a month as slipping in the car became an exercise in foot placement and weight management. 

 

Think things through. You are as miles pointed out on a swap haven, almost every type of swap has been conceived or witnessed on here and elsewhere, V10, V12, flat 4, rear mount V6, rotary (2, 3, and now even 4 apparently), 4-cylinder (even a 4g63, among SR20, FA22C etc), even electric. The reasons people have done it or started it range from because they had access or they were bored to pointing out the benefits in engineering, serviceability, familiarity, or whatever. Narrow it down, to a couple candidates that have good pros that outweigh any cons and ask specifics. One thing that might help in reality check terms is asking how much people have spent getting the swap into their cars, because in the JZ side of things the average cost is a suggested 7-10k just in getting the engine in and running with minor supporting systems like coolant and fuel, not including chassis, rear end, suspension, brakes.

 

[TUME]

I think you should look at british market for JDM engine. 

I can feel your pain, we have here in finland maybe even more tight regulations with cars. I can go +20% with power, +25% displacement and so on. Not funny at all. That is main reason i went to SR. It just fit with regulations, but i can always tune it. Lets say double the horses for a start...😁