High horsepower L28 turbo questions

[Micah]

Hey guys, I have a few questions for the high horsepower drag guys. I have been researching how to build an L28 (what pistons, rods, head, etc.). It may seem like a topic that comes up a lot, but when I say "high horsepower" I don't mean 300-400whp. 700whp is more my taste.

If one were to build an L28 using
an F54 block
stock crank (unless there's a better aftermarket option that is redily availible)
forged rods
forged pistons (9.5:1-ish CR)
ARP stuff throughout
P90 head with port work
MLS headgasket
custom grind cam
homemade intake with a large plenum and 80mmthrottlebody or something like that (my Honda has a 70mm)
BW 366 turbo (or something like that)
Megasquirt

Obviously a build like this takes MANT more pieces than just the ones listed, but those are the big ones.

I have been in high horsepower stuff for a while. My father and I own a performance dyno shop and I have built many a 10 second and 9 second car. It just seems to me that, if the crankshaft holds up, there's nothing stopping one from making 700whp from a setup like this. It makes me wonder why no one seems to be doing it. Or perhaps they are and just don't go on the internet often. Advise me!

Edited April 23, 2014 by Micah

[dexter72]

 

 

Look up Jeffp, or look for his web page, His page may have the info your looking for, High horspower L engine, has a ton of info from engine to rear end about his car and build.

[Xnke]

What makes you think you need 700hp? Do you need to put an S130 in full street trim into the 9's?

 

Are we building an L for a Cedric? If so, that's somewhat more reasonable...

 

To hit your marks, consider bore strength, heat transfer, and airflow management before you start into the money. The stock rods and crank will hold that with minimal prep, the stock pistons will show their true colors about 450hp.

 

You need some stronger, lighter pistons, and you need to prep the cylinder head and intake manifold to your airflow needs. To make 700 boosted wheel horsepower, you are looking at building a 350hp N/A engine...which is fine and can be done. You will probably be in 10kusd or a little over, then you will need to consider the transmission and structure of the car body.

 

The stock intake can do it...but that doesn't make it the best way to go. You can do it under 7500rpm...which might be, depending on your transmission.

 

Get the head worked by the best in the business, get a cam fitted that fits the head flow, and match your intake to the flow needs. Prioritize equality over massive flow...if runners 2-5 flow 250cfm, but 1 and 6 only move 180...then an intake that flows 200cfm on all six will make more reliable power.

 

I'm interested to hear what chassis this is going in, as well as the transmission plan before I speculate on how I would approach this.

[Micah]

Look up Jeffp, or look for his web page, His page may have the info your looking for, High horspower L engine, has a ton of info from engine to rear end about his car and build.

 

Thank you! I'll research him and his builds.

 

What makes you think you need 700hp? Do you need to put an S130 in full street trim into the 9's?

 

Are we building an L for a Cedric? If so, that's somewhat more reasonable...

 

To hit your marks, consider bore strength, heat transfer, and airflow management before you start into the money. The stock rods and crank will hold that with minimal prep, the stock pistons will show their true colors about 450hp.

 

You need some stronger, lighter pistons, and you need to prep the cylinder head and intake manifold to your airflow needs. To make 700 boosted wheel horsepower, you are looking at building a 350hp N/A engine...which is fine and can be done. You will probably be in 10kusd or a little over, then you will need to consider the transmission and structure of the car body.

 

The stock intake can do it...but that doesn't make it the best way to go. You can do it under 7500rpm...which might be, depending on your transmission.

 

Get the head worked by the best in the business, get a cam fitted that fits the head flow, and match your intake to the flow needs. Prioritize equality over massive flow...if runners 2-5 flow 250cfm, but 1 and 6 only move 180...then an intake that flows 200cfm on all six will make more reliable power.

 

I'm interested to hear what chassis this is going in, as well as the transmission plan before I speculate on how I would approach this.

 

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.

 

As stated, I plan on making my own intake manifold. I would be using the Z32 turbo transmission.

 

 

I know what it takes to make high horsepower in other platforms. I'm asking if there is anything specific to the L28 engine that would inhibit me from doing so.

Edited April 23, 2014 by Micah

[FlawleZ]

I'm sorry but you do not need to build a "350 HP NA engine" to achieve 700HP in turbo applications. You do need to build/prep the engine accordingly. What you DO need to do, and this is by far the most important factor, is size your turbo properly.

 

Is this  going to be a drag car? Road course car? Street car?

[Xnke]

Suit yourself. Study up on the existing 700hp+ l28s in existance.

 

I have, I know what it took others, and I know that you'll ignore it and break many engines before you either give up and do it right, or say it can't be done and move on.

 

Best of luck with your build.

[Micah]

I'm not trying to start a "why do you need that much" or "I don't think it can be done" battle.

What I'm really asking is why have very few people done this? Are there limitations to the block that simply cannot be overcome? Does the head crack at this much cylinder pressure? Or maybe the reason very few people have done this is simply because the L6 croud is more into N/A setups.

I do know how to build engines and fabricate turbo systems. My 1.8L Civic is a daily driver that runs 11's on street tires. I have built many other 10 and 9 second cars besides.

 

Thank you all for your input. If you have a motor that makes this much power or know of someone who does, please inform me as to any limitations that had to be overcome. I cannot find any in my research so that is why I am posting.

 

 

 

To answer FlawleZ' question, the car will be a drag car that I drive around on nice days along with an occasional road course event. It will certainly not be dedicated to the road course though.

Edited April 23, 2014 by Micah

[Xnke]

You don't see it done in the US much because more than 450hp starts costing cubid dollars. The first 450hp is very cheap.

 

The problem isn't blocks or rods or heads or cams, nor manifolds or turbos. those problems can all be solved with money. The problems show up in the details, in heat, and in tuning.

 

Nobody wants to spend the money doing the hard work...they all want to cram 35+lbs of boost on methanol/water injection with shiny intakes, big turbos, stock ports and mild cams, expecting big power because the 4-valve Hondas and Toyotas can do it till the rod bearings go.

 

I will state that you need less than 28lbs of boost to make 700hp.

 

And you can hold it at peak power for 5 to 10 minutes at a time at that level...north of 1100 was done here in the 80s, and more than that has been done in Japan and Australia.

[mattb3562]

I know a guy that that's boosted l28 made 748 at the flywheel. Not sure what turbo, but it hit 34 psi

[seattlejester]

...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).

Edited April 23, 2014 by seattlejester

[FlawleZ]

Not to sidetrack the thread as I hope this contributes to the OP, but Xnke why would you make an arbitrary claim such as:

 

"I will state that you need less than 28lbs of boost to make 700hp."

 

This is entirely depending on MANY factors. Most importantly the turbo size. A stock T3 from an L28ET @ 28 lbs most certainly will never make 700HP. If it even achieves 28lbs without disentegrating. 

However, an 78MM will make MUCH more than 700HP @ 28 lbs. This is just 1 of many factors.

[Micah]

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.

[NewZed]

Describe one of your typical 1000 HP engine so that people have a point of reference.  Brand (GM, Ford, Mopar...), model, type of work done, turbo, nitrous, etc.  "We run a dyno shop and pop out 1000 HP engines on a regular basis" doesn't tell anyone anything about what you know.  You could just be full of BS.

[dexter72]

FlawleZ,

 

What Xnke is stating is. If the combintion of parts and overall engine work is up to par, including the tune. You don't need over 30psi of boost to get 700hp. We know that a stock t3 and 28psi do not work. There are many posts about choosing the correct turbo, cam, and headwork to achieve certain HP goals, without even needing an intercooler.  

 

Look up JeffP or wait for Tony D to chime in. Jeffs engine is in the range that the OP was asking about.

Edited April 23, 2014 by dexter72

[AkRev]

If I was an evil man, I would enjoy starting threads like this all just to watch the reactions. 

 

But on a serious note, money is always the main limiting factor. Besides that, your posts are coming off a little stuck up. (I am not trying to be a jerk, just calling it how I see it.) You list off some good things your first post, but it looks like you are missing the experience that comes from doing this type of work.

Ringing the block, Head work, upgrading the head bolts and so on.

 

If you want to do it, go for it, I will support you as much as I can. If you want to get others to support you, Do your homework, study, and do not compare apples to oranges. Comments like "Honestly, compared to what I'm used to, 700whp is rather low." will probably get people annoyed at you.

 

If you are just after a numbers game just so you can say you have 700hp, I would bet that you will not enjoy your car as much (be so hard to drive the thing.) Also, I will say that most of these 1000hp cars are (more than likely) much heaver than the Z's unibody. 

 

One last point I will toss out there, if your dad is in this business, talk with him! I love when my kids come to me asking questions that I can answer until they get bored of me. 

Edited April 23, 2014 by AkRev

[Micah]

Sorry for comming off stuck up. I definitely didn't want to. Thanks for a good reply, AkRev, and for calling me out.

The stuff we usually deal with is the new Hemi engines and big block Chevy's. The Mopars are all drag cars while the BBC (and LSX motors) are salt flat cars. We do the occasional import but it's mostly v8 stuff. These cars all have either 70mm or larger turbochargers or F1 superchargers.

I am just using 700whp as a placeholder. My real goal is to run high 9's in a period correct, stock body S30. Propper machine work would of course be done to the block and head. This would include decking, boring with a torque plate, balancing, etc. I left out the details from my original post because I feel that those things go without saying in a build of this caliber.
You mention o-ringing the block. Does that mean you think it will be nessicary? I only ask because that is not something done on Hondas, SR's, or Toyota's at this power level.

Again, sorry for coming off stuck up. I just didn't want people thinking I was 16 years old and had an overwhelming desire to play Fast & Furious.

My dad is indeed a wealth of knowledge. However, I'm looking for information on this engine specifically. When it comes to tuning I still have much to learn from him.

 

Thanks again for your help, AkRev.

[AkRev]

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?

Edited April 23, 2014 by AkRev

[madkaw]

Please build this 700hp monster and document everything here please. We need a thread like this since we haven't had any in a while. Wish I had some info to contribute, but I'm not as knowledgable as these other guys with the turbo stuff .

From what I have read , Jeff P stopped wasting a lot of money and time on the blocks because these lower ends could handle that hp levels, but the rest of the motor needed help.

Good luck

[mrcheeze36]

JeffP's site

http://www.angelfire.com/extreme/280zxt/

[310z]

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.