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Reconsidering my L28ET build


Shanks

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This is my 2nd 240Z project. First one was kept original, this project is a restomod. Car will mostly be driven on the road and taken to shows and a track occasionally. Really don't want to do a build project if it's going to end up being slower than today's stock sports car from the factory. 

 

I put together a L28ET build a while ago for my 71 240z. PDF attached with the rough details. My goals were to try my best at breaking 400hp at the dyno, but after reviewing similar set ups here on this forum I am wondering if I can really make those numbers with my build plan. What say you?

 

If not, I am considering doing a 3.0 stroker, which would add at least 3-4k to the cost based on my current estimates. At that point, the total performance expenses would be around 12k or more plus unexpected costs. The stroker would put me well over 400hp (which I would be very happy with), but I would also need to spend more money on strengthening the chassis at that point, and if I wanted more HP down the road it would be tough to squeeze any more out of it.

 

If I am willing to spend 12k on the engine alone, would I not be better off going with an RB25DET or 2JZ? It seems like either of those platforms would actually be cheaper than a stroked L28ET and for the same money I could get a lot more power.

 

(I have separate sheets for my brake and suspension needs, but ignore that for the sake of this topic.)

 

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With your target of around 400hp, i would do a V8 LS/T56 swap without hesitation.

 

I have one in my BMW E36 track car currently.

 

Easy to get those numbers, reliable, easy to get parts, easy to work on, fit nicely in your chassis without affecting balance too much.

 

Cost wise, i presume it would be around the same as a RB swap if not less....

 

But yeah, its a GM engine.... ;)

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Damn when you spell it out like that cost add up quick. (note: I am no expert but...) at 400hp that trans is going to break. I think 300 is really doable and damn fast for 2300lb car. That is where I guesstimate mine at 15lbs. At 400lb you are pushing cast pistons and may need some port work and a good tune/meth injection. 

12000k to spend you might as well go 2j or rb30. TimO knows high HP L28

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With your target of around 400hp, i would do a V8 LS/T56 swap without hesitation.

 

Yes, you're exactly right. I also think that this is the obvious choice, it's just that I cant bring myself to do an LS swap on my Japanese dream car. At first I didn't even like the idea of the 2jz but after comparing them to the Rb25 I am willing to make the compromise.

 

However, if finances continue the way they are right now I do plan to scratch my LS itch with a BMW e30! We will see.

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One thing I think you should consider is weight. the 2JZ is a HEAVY motor. The RB I believe is heavier than the L, but lighter than the 2JZ. RB will be hardest to find, and find parts for, while the 2JZ is easy to find, and make impressive numbers very easily. The L series will be the lightest, and least powerful, but, if this matters to you, will also be period correct, and most fitting for the car. I personally don't see the point in more than about 500 crank HP in a Z unless you're drag racing, and the L series is capable of that with some work.
 

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The period of the engine used to be more important to me before I had a second Z that was completely stock and restored. Now I just want to have fun. The Z this is going in is rough around the edges and not very valuable being it's not a series 1, but I'm still keeping it Japanese and straight 6. Looks like weight is similar between the RB25 and 2JZ, but I do share your concern about the weight and also the shift of weight forward. I remember reading that with either of these engines it pushes a lot more weight towards the front of the car, which can throw off its center of balance fairly well.

 

The more I research this the more I feel confident in my decision though. I see a lot of people pulling out there L28et for an engine that can make more power. I really like what this guy has to say: https://youtu.be/TJYUOGZzbWo

 

As far as driving for fun in the mountains and back roads, is a build around 600 hp and appropriate mods for the suspension just too much to enjoy? I'm seeing a lot of Datsuns with this kind of power.

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As far as driving for fun in the mountains and back roads, is a build around 600 hp and appropriate mods for the suspension just too much to enjoy? I'm seeing a lot of Datsuns with this kind of power.

Well, I haven't driven a Z with that much power or even close to it, but my gut feeling is yes, that is entirely too much power. It's a light car, and 600hp is a lot of power, period. As I said earlier, I don't see the point in having much more than 400hp in a Z. It doesn't have any kind of driving aids, or modern suspension designed to make use of that power, and it has a short wheel base.

 

I think a lot of people building high HP Zs are either looking for straight line performance, or they're doing it for bragging rights. I don't believe that any of these people are capable of taking a Z with that much power around a track and actually using the power and potential it has.

 

IMO, for a car that is built for twisty roads, 300-400hp at the crank, and make it light with a great suspension and brake setup. Less impressive acceleration, but will likely be overall more fun and manageable to drive in the mountains.

 

Also depends on if you're willing to flare the car. If you want to keep the stock body and limit tire width, you may want to consider restricting power to what you can put down to the road.

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Well, I haven't driven a Z with that much power or even close to it, but my gut feeling is yes, that is entirely too much power. It's a light car, and 600hp is a lot of power, period. As I said earlier, I don't see the point in having much more than 400hp in a Z. It doesn't have any kind of driving aids, or modern suspension designed to make use of that power, and it has a short wheel base.

 

I think a lot of people building high HP Zs are either looking for straight line performance, or they're doing it for bragging rights. I don't believe that any of these people are capable of taking a Z with that much power around a track and actually using the power and potential it has.

 

IMO, for a car that is built for twisty roads, 300-400hp at the crank, and make it light with a great suspension and brake setup. Less impressive acceleration, but will likely be overall more fun and manageable to drive in the mountains.

 

Also depends on if you're willing to flare the car. If you want to keep the stock body and limit tire width, you may want to consider restricting power to what you can put down to the road.

 

All of this is exactly why I reconsidered any sort of high horsepower goals or outrageous engine plans. If you really want 400hp LS would be the easiest and, at least long term due to parts availability, the cheapest. I didn't want to cut into my wheel arches since they were in pretty good shape, Some have fit 275 tires on stock arches, but even stuff like that starts getting expensive. If you want stock body like me, and you don't want to mess with flares or widebody, you're a bit limited by what you can realistically put to the ground. Excessive torque is just gonna make you burn through tires or clutches

 

For the money, especially on this sort of car if you just want to have fun, you can't beat well tuned suspension and brakes. Horsepower looks good in magazines but isn't actually what gets you around a track or a fun twisty road. 

 

As an aside a more direct comparison to the RB25 would be the 1jz. Especially the VVT-i. Single turbo, variable valve timing, 2.5L, closer in cost, but arguably more reliable. Only reason not to choose it over the RB25 would probably be slightly less swap documentation and wanting to keep it Nissan. 

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Honestly do what you want.

 

Will you be happy with the, easier, cheaper, faster, different option? Unless your end game is just a number, sit down and think what you want to do.

 

A couple points:

 

Complaining about transmission options is moot. Once you step out of the 200-300hp range chances are regardless of the engine you are going to have to step up to a beefier transmission option whether that is the CD009, R154, T56, etc.

 

The 0.2 Liters of displacement really isn't going to push you over the edge there. That money would be much better invested in a better flowing turbo/performing turbo. Spend $200 more on the turbo and save 3-4k...

 

Obviously I'm biased, for bang for buck, probably the 2jz is going to be an easier route once all is said and done. More parts readily available, machine shops can order bearings and such straight out of a catalog, etc. 

 

My list approximated

 

1jz bell housing - 300

1jz flywheel - 300

stage 1.5 clutch kit - 400

rear sump oil pan - 300

engine mounts - 300

oil feed and drain kit - 150

FFIM - 100-700

Turbo manifold - 400

Turbo - 900

Gaskets - 450

 

That is 4k or so right there not including the motor

 

That doesn't even include the parts I already had

Coil packs - 150

ECU - 500-2000

Injectors - 100-400

Throttle body - 50

Intercooler piping - 150

Blow off valve - 50-150

Intercooler - 50

Starter -100

R154 transmission - 800

Custom drive shaft -300

Exhaust - 150

AN fuel lines -150

Fuel cell -200

Diff - 200

Axles - 600

~5k or so?

 

So possible, but you are going to get hit with a lot of unexpected expenses. I really wouldn't try and do a big swap like that, you definitely are going to loose motivation. At the end of the day it depends on what makes you the happiest when you open the hood. 

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600hp for backroads and mountains is pretty silly unless you have huge long sweepers. The brakes and suspension to handle sudden changes with that much power would be pretty outlandish as well.

 

Also not sure if there are loads of datsuns out there pushing 600+hp. They are out there for sure, but I imagine the word terrifying to describe how they are to drive.

 

Have you been in cars this light with this much hp? We are talking like a v8 swapped miata in terms of power to weight. 

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I'll throw my Hat into the ring. 

 

1: Buy 2 F54 Turbo  blocks. Freshen one with just rings, a quick ball hone and bearings if needed. This is going to be your  " Mule " testing block while you sort out your Fuel injection and Tune. Don't spend a lot of money on this block as it will be a scarificail Lamb for mistakes.

 

2: Slowly build your " Good " engine block with all the good components. If you want a reliable 350 to 400+ HP, this is the engine that your put the Forged pistons in. With a Turbo, you don't need a stroker and you don't need to turn big revs  . Revs = $$$$$  Stock polished rods with ARP bolts are very strong and can easily with stand 500 HP. 

 

3: MS 3 is OK... but there are better systems out there. Try and pick up a used Haltech, Link or Adaptronics. 

 

4: ACT clutch would be my last choice. Seem to be a lot of quality control issues with ACT. Same with Spec. Go with South bend or Clutchmasters. BT VW/Audi guys find that South Bend and Clutchmasters seem to be the most reliable, short of Multi-Plate Tiltons. 

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Here's a video from one of out local Road racers using an L28 with a fairly simple Turbo setup ( T3/T4 ) . 400 HP reliably at 15 lbs boost  and basically a stock block with forged Pistons. No trick internals ( other than good Forged Pistons ), stock stroke  and bore .040" over. Stock rods ( Polished and shot peened ) with ARP studs. Stock crank. Everything has been balanced of course.  

 

 

Note: Trans-AM that passes him is a local Hillclimb car with over 500 HP. Keeping revs down ( 6,500 max ) is one key too longevity. Turbo cars do not need big revs to make power.

 

Watch at 1.14. That's what 400 HP does on a Race Car with soft Goodyear race slicks. Should be enough for any street car.

 

https://www.youtube.com/watch?v=1BiF8-kIZCk&feature=share

 

17807621_10203373967747496_1370905431511

 

 

 

 

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I really dived into creating a parts list for the 2JZ build tonight and would love to do it, but the more I look into it the more I am realizing, while I could do it and would love it, I am not sure I want to spend that kind of time and money on the 240z, no matter how much I love it. For the 2JZ it would involve a significant amount of additional fabrication as well as higher costs all around in other departments, especially labor as I just don't have the time to learn and do this myself. I would rather make sure I take care of my retirement goals every year and have a kick ass L28et I can put right in myself and have the project finished in a few months if I want to. The diminishing returns I would get for the amount of work for an extra 100 or 200 HP doesn't make sense on the 2JZ, but I did enjoy the feedback from you guys so thanks for your input! There's nowhere like here to have a good convo about these cars. I tried to give out some likes but I don't have the rep I'm afraid.

Edited by Shanks
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400hp is fairly straight forward with an L28 I don't know why people make it such an impossible task. 

Really its just a airflow bottle neck problem, which with a stock L28 is the ports themselves which a lot of people take care of, then the stock tiny cam and then the intake manifold runners need ported themselves. 

There is TONS of info on making a powerful L series here on this very forum. I've done months and months and months of research and Im building a 500+hp L28ET. No stroker yet, but a rebuilt stock bottom end (arp rod bolts is the only real upgrade) and I'll be playing around with porting the head, intake manifold, exhaust manifold will easily get me over 400whp, with a nice balanced power band. Ie similar HP and TQ and not an over abundance of torque down low and fading in the top end. 

I also have will have two L28ets and the second one will be forged. First one is to get in the car and back on the road again after a few years of sitting. 

~Alex

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Building not built.  Airflow bottle neck problem.  "playing around with porting the head, intake manifold, exhaust manifold will easily get me over 400whp, with a nice balanced power band." .. I know this and and I haven't even started yet.

 

C'mon.  This is the internet.  Anything is possible.  In our heads.

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