High horsepower L28 turbo questions

[thezguy]

...He's saying the engine in NA form with all the port matching, head work, etc would be capable of 350hp. Not necessarily to build an NA engine and then boost it.

 

I think rebekahz made it almost into the 10's with a stock ls2 which is 400hp 400tq rating from the factory. The Z chassis is light I think it's the same weight as a miata with a passenger. You don't need 700hp to break into the 10's.

 

You have to remember that it is older technology. 2 valves per cylinder, single overhead cam etc. It isn't impossible, quite a few examples of fairly high hp cars using the L-block if you look around, electromotive had something around that much hp back in the 80's, but it would be easier with other engines on the market and the Z chassis accepts them pretty readily.

 

That's probably the reason people don't do it very often, not that the engine isn't capable, but it requires quite a bit of work, more so then buying a 2jz and adding a big turbo would (which would get you roughly in the same range).

 

I laughed a little when i read this.. Have you seen the LS platform?

Edited April 24, 2014 by thezguy

[30 ounce]

Thank you all.

 

Xnke, you mentioned heat problems. What do you mean? Do certain cylinders get hotter than others leading to detonation? Please be more clear.

 

As for tuning, my father and I run a dyno shop and have pumped out many 1000whp+ cars. That won't be an issue. Honestly, compared to what I'm used to, 700whp is rather low.

 

I know I can easily make this power with a 1JZ or 2JZ, but I really want something period correct. Just because.

 

 

So it seems what you all are saying is that with a built bottom end, head work, and a properly sized cam and turbo, this goal is pretty attainable. Very cool.

 

 

#5 gets hot and causes detonation.  I think Tony D had a head cooling thread showing how to deal with it.  Datsun had 700 hp L's in the 70's and 80's for road courses.  Basically all stock bottom ends with shot peened rods.

[Xnke]

I've sent along a PM with some relavent information; along with some links to photo-filled threads to show you some about the cooling aspects that need to be addressed. Also, Honsowetz's book. Get it, just for the photos...alot of the actual information in the book is wrong/erroneous.

[roger280zx]

^^^^The stock pistons won't get anywhere near 700 hp.

Edited April 24, 2014 by roger280zx

[TimZ]

#5 gets hot and causes detonation.  I think Tony D had a head cooling thread showing how to deal with it.  Datsun had 700 hp L's in the 70's and 80's for road courses.  Basically all stock bottom ends with shot peened rods.

http://forums.hybridz.org/topic/59029-head-cooling-on-cylinder-5-solutions/

 

Actually there are several posts in this section of the FAQ that should be helpful regarding various aspects of the prep work that needs to be done.

http://forums.hybridz.org/forum/90-l-series/

 

Head cooling is one important aspect, but since you are working with a non-crossflow head, keeping heat out of the intake air charge is critical as well.

 

Xnke already touched on it, but I think one of the biggest reasons that you don't see that many 700hp L-series is simply that at this power level details that you could ignore at 350hp can no longer be ignored, and for most this just becomes overwhelming.  The information is out there (mostly), but there is really no cookie-cutter "buy this bag of parts" solution that will get you even close.  Yes it's been done, but you are still really pretty much on your own to make sure you've covered everything, and that it all plays nice together, and it probably wont for the first several tries.

[roger280zx]

And don't forget that if you want to run high 9's in a s30 700 is overkill.  Zgad ran VERY deep into the 9's on a 700whp 2j-and that is a big HEAVY engine.

[Six_Shooter]

One of the reasons the L series is not pushed that far often is an RB is available and it is considered a better platform to start with. 700 hp with an RB is easy and reliable. If you are going to spend a lot of money sometimes it is wiser to start with a platform that has greater potential.

 

In this same vein, it's much cheaper to get those kind of HP numbers from other engines than the L-series, which is why few people try to push the L-series. It's a dollars and cents, and even time based decisions.

 

I can throw any number of late model engines in an S30, for less money than it would take to make an L-series put out these kind of numbers, and probably spend less time doing so, because of the advances in technology.

 

Don't get me wrong, the L-series is a tough reliable engine, and 5 years after buying my S30, it still has the L-series in it that it came to me with, although I did add a turbo and EFI system to it. I bought the car with the intention of swapping out the L-series within the first two years of owning the car. I've actually had the engine to go into the car longer than I've had the car! The L-series has impressed me so much, I just can't bring myself to swap it out yet, although I'm getting REAL close to that point now, where I want more power, and just don't want to spend the time on the L28. For me one of the things I really don't like about the L-series and is a large reason why I won't bother trying to push it anymore is the fact that it's a non-crossflow design. The intake gets really heated up from the exhaust (yeah there are coatings and heat shields that can be used...) I'm also terrified of a fuel leak happening from an injector that dribbles down on the the hot exhaust. It hasn't happening in this car (knock on wood), but I have have had an O-ring fail on me in another vehicle, and filled the intake recesses with fuel. This isn't really a concern for a carb equipped L-series, but I like my EFI.

 

The limiting factor in any engine build is getting enough air (and fuel) in AND out of an engine. Getting this to happen with an L-series head seems to be some secret, Voodoo, or black magic. So if you can figure that out, go for it.

 

I just question the "period correct" thing, EFI, and arguably the addition of a turbocharger* is already taking away from being "period correct", so it seems like an odd term to use.

 

*Yes, I know there were S30 turbo systems in the '70s, but they were never equipped stock, and the '70's turbo systems that were available are usually much different in layout and design than what is being used today, so I'm not sure how "period correct" you can be and still meet your goals, when it comes to the turbo system.

[Xnke]

Not to mention that if you DO get 700HP in an S30, you won't drive it on the street...

 

It's not an old american muscle car, there is NO room to bolt in the safety cage you'll need/want and be able to get away without wearing a helmet and gloves everywhere you drive it. To not wear the helmet and gloves is to invite instant death the first time you screw up.

[Micah]

No worries, Sorry also if I came off bad too, I was trying to be funny and its hard to come off through text.

All I can do to help is make a few points,

Block, F54 is hard to bore out big(but possible), I have seen more have luck with the N block, Also I would o-ring it.

Crank, I have no idea the limit for the crank. Hopefully someone else can chime in on this.

Seems like you have a plan for the rods and pistons.

Head, Lots of debates about this part, do you have one already to start with? these are non crossflow heads, and they do take some experience to flow right and efficiently. Look into upgrading the bolts, shaving, and cam spacing/shimming to meet your needs. 

Intake, noted about the custom build, you looking into short or long runners? <- that makes a big difference. 

 

How are you planing to back up this power, Clutch, halfshafts, transmission, Body stiffing and so on.

There is lots of good information on Hybridz, Sometimes it is hard to find using the search feature on the website. However, Google site search is always your friend.

 

Good Luck

PS, I know this list is very incomplete... but I am hungry, and my caring to hunger ratio is low. 

 

Also, got some pics of the base car? Also, are you planing to use this car for promotion of your shop?

 

Haha! No, you definitely didn't come off bad. I'm new to this forum...just look at my single digit post count.

 

Good info. I do remember reading the F54 block was stronger because of paired cylinders and that's why I chose it in that list.

 

As for the intake manifold, I plan on using a large plenum with short fat runners. I will experiment with that more in a very accurate engine building software we have but that it the setup that made my Honda come alive. I will try to replicate the Edelbrock Victor X intake.

 

Other stuff....Some sort fo twin disk clutch (haven't researched which type yet), Z32 TT transmission, R200 out of a Q45 with 300ZX Turbo axles with an aftermarket stub axle. I'm sure I'll blow diffs a lot so I'll just stock up on them.

 

This will definitely be a promotional car showing both what our shop is capable of (to the import crowd) and to showcase our fabrication work (I plan on making the intake manifold, exhaust manifold, intercooler piping, exhaust, cage, and all the other little stuff). It will also be my personal "fun on the weekends" car.

 

Sorry, no pictures of the base car... I don't even have the car yet! I'm just researching the best engine options for when I get out of college.

 

If I do go this route then yes, I will most definitely document it! Thanks again for all the information.

 

 

 

 

edit: I posted that before the page was refreshed. Thanks for the info and links to the cooling stuff. That's exactly what I'm looking for.

 

As for the period-correctness, yes, that certainly different from person to person. I personally think an L is much more period correct than an RB or JZ. 

 

The non-crossflow head is definitely going to be a bottleneck in the whole project. I'll continue to research how to make them flow better and stay cooler; hot air coming in is just asking for knock. Thanks agian, guys! Right now I've narrowed my options to this L28 or a 1JZ making the same power or more (there goes ALL period correctness).

Edited April 24, 2014 by Micah

[FlawleZ]

The L28 is most certainly capable. If your still considering swapping engines, you would be far more "period correct" as well as staying in the family if you used a VG30 which is more than capable of meeting your goals.

 

I apologize if I missed it somewhere, but what fuel are you expecting to run? I'm assuming E85?

Edited April 24, 2014 by FlawleZ

[TimZ]

Here's another pretty valuable thread regarding engine prep that probably ought to be a sticky:

http://forums.hybridz.org/topic/106082-power-drain-from-timing-chain/page-2

 

Search on PMC raceengines' posts and take a look at the attention to details in his engine builds.

[seattlejester]

I laughed a little when i read this.. Have you seen the LS platform?

I knew someone would bring it up...doesn't change the fact that L motors are still old.

 

The LS motors are modernized, refined, etc, but yes the 2 valves per cylinder is still old. Simple, cheap, etc, still old.

[Micah]

The L28 is most certainly capable. If your still considering swapping engines, you would be far more "period correct" as well as staying in the family if you used a VG30 which is more than capable of meeting your goals.

 

I apologize if I missed it somewhere, but what fuel are you expecting to run? I'm assuming E85?

 

I'd like to keep the engine an inline 6 for purist reasons; nothing more.

 

Nope, you didn't miss anything. I will most likely be using C85 which is a new fuel from VP Racing. It's 85% ethanol and 25% race fuel. We've had much better results with it as opposed to E85. It's consistant (it will ALWAYS be 85% ethanol) and is much higher octane.

 

Here's another pretty valuable thread regarding engine prep that probably ought to be a sticky:

http://forums.hybridz.org/topic/106082-power-drain-from-timing-chain/page-2

 

Search on PMC raceengines' posts and take a look at the attention to details in his engine builds.

 

Thank you!

 

Edited April 24, 2014 by Micah

[roger280zx]

Horse before the carriage much?

[Tony D]

"Why? Because I want to go 9's in an S30 and be period correct.

 

Why would I build an N/A engine to turbocharge it? That's rather silly. And it would certainly not cost $10K."

 

Define "Period Correct"---what 'Period'? 70's, 80's, 90's? Each ranges from impossible to possible.

 

"It won't cost"---HAHAHAHAHA I love that. Keep your receipts.

 

There are plenty of 9-second S30's in Japan, you are just looking in the wrong places to get the impression that it is not common.

In fact, quite to opposite is true for at least the past 20, if not 30 years!

[thezguy]

I knew someone would bring it up...doesn't change the fact that L motors are still old.

 

The LS motors are modernized, refined, etc, but yes the 2 valves per cylinder is still old. Simple, cheap, etc, still old.

 

 

If it's not broken don't fix it. The point of which im trying to make is that your argument of the engine being of an old design has no bearing on if it can make 700rwhp.

Edited April 26, 2014 by thezguy

[skirkland1980]

Look up Dookies in Japan and Kameari.

[AZGhost623]

I believe TimZ  has a 600HP Z... 

 

 

build info

http://forums.hybridz.org/topic/55924-went-to-the-dyno-with-the-gt42r-today/

[seattlejester]

If it's not broken don't fix it. The point of which im trying to make is that your argument of the engine being of an old design has no bearing on if it can make 700rwhp.

 

I'm not really sure what you are thinking.

 

My statement was that the L-series is an older design, and that it is easier to extract power from newer engines, which is to answer the OP's question of why not many people aim for higher hp with the L-series motors.

 

Your rebuttal was to laugh and say that 2 valves/cylinder and a single OHC is not an old design because it is still used specifically in the LS motor.

 

My statement was to reiterate that even though it is still used, the L-series motor is still an old design. 

 

Your rebuttal was to state that if it isn't broken don't fix it. Also stating that an engine based off of an old design is still capable of getting 700hp.

 

You have completely missed my point. My point was to answer the OP's question why people don't pursue high hp L-series builds. The short answer is because it is of an older design. It takes skilled professionals and quite a bit of work to extract that much power from an older engine like the L-series motor. Where as many more individuals can install a V8 of any sort or an RB or a JZ with comparatively minimal effort using pre-existing mounting kits, bolt on a big turbo and supply extra fuel and get into a high hp range easily. 

 

To reiterate. The reason that many people don't do high hp L builds is because it is easier to extract power from a newer motor for those without the knowledge or the shop capabilities to do so.

 

Take it however you want I suppose.

 

 

 

700hp for a fun weekend car with a full cage doesn't sound like a very good idea. Interior is pretty small, if you are of decent height your chance of hitting one of the bars will be pretty high. Please document the build process, would love to see the work involved. Granted I have seen a chart out there that shows the flow rating between heads. Even a well flowed P90 was below the flow rating for the head off of a KA24de motor. It's going to be an uphill battle if you decide to go L-series, still hoping you do though.

[TimZ]

I believe TimZ  has a 600HP Z...

I heard something about that somewhere...