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Stokked240z

So many questions (L28, California Datsun, Build options)

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Hello all....My name is Austin and I have so many questions!

 

So, I'm sorry if some or most of this has been covered but there are 500+ pages of threads just talking about L28's and have not found what I'm looking for, so... I'm gonna had another!

 

I recently acquired a 1973 Datsun 240z with the original L24 & 4speed. I had a stock long block rebuild of the L24 quoted by a shop near me, which came out to be roughly $5000 ($1700 in parts). Which is more than I want to pay for a stock rebuild (150hp maybe). So I have decided to entertain the possibility of an L28 build instead. But because I am so new to the Datsun universe / engine builds in general, it is becoming difficult to see the start point, let alone the end point of this project.

 

I would very much like to see some (all inclusive) comments. Meaning, builds that people have done before and are happy with that include as much detail as possible. Sort of a one stop shop for people looking to build an L28. Keep in mind, I might not understand all of it. So in writing your comments, please keep them simple. I'd greatly appreciate it! 😊

 

The goal:

* 250-350 HP

* 11:1 CR

** A street performance car | Occasional track day car **

 

My Questions:

1: Has anyone bought from California Datsun  ??    https://www.californiadatsun.com/long-block-short-block-engines/datsun-240z-280z-l28-n42-head-l28-flat-pistons-engine.html

* I found this and thought this could be a good starting point for an L28 build. What are your thoughts? Anything I should be concerned about?

 

2: Build options! I know a lot of L28 builds are out there but lets assume that I begin with the engine listed above. What are the options to push that to 250-300 HP with 11:1 compression? Is adding compression from 10:1 to 11:1 something even worth worrying about?

* Please include all details!

 

Thank you all! I greatly appreciate it!

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Stokked,

 

Welcome to Hybridz!

1 hour ago, Stokked240z said:

I had a stock long block rebuild of the L24 quoted by a shop near me, which came out to be roughly $5000 ($1700 in parts).

That seems high but I haven't priced an engine build since 2008.  For reference, my Rebello (Google it) built long block wasn't much more than $5K back in 2008 for a long block build with forged internals, custom cam and mildly ported head.  You can do the math.  I'd recommend shopping around, and be sure to read about HZ member experiences with California Datsun.  I believe they used to be called Datsun Parts.  

 

2 hours ago, Stokked240z said:

I would very much like to see some (all inclusive) comments

Good luck with that!

 

2 hours ago, Stokked240z said:

Has anyone bought from California Datsun  ?

Not personally, but search around there are quite a few people who have paid for their services.

 

2 hours ago, Stokked240z said:

https://www.californiadatsun.com/long-block-short-block-engines/datsun-240z-280z-l28-n42-head-l28-flat-pistons-engine.html

* I found this and thought this could be a good starting point for an L28 build. What are your thoughts? Anything I should be concerned about?

Search and form your own opinion about California Datsun, a.k.a Datsun Parts.

 

2 hours ago, Stokked240z said:

What are the options to push that to 250-300 HP with 11:1 compression? Is adding compression from 10:1 to 11:1 something even worth worrying about?

Talk to Rebello Racing (or read more HZ) and get ready to open your wallet. You won't be able to run pump gas with that kind of compression.

 

2 hours ago, Stokked240z said:

* Please include all details!

It's all here, right at your fingertips.  I certainly don't have the time or will to spoon feed information maybe some other nice soul will.  FWIW, the best way I've found to search Hybridz is to open a new tab, go to Google type in your search term followed by "site:hybridz.org".  For example "250hp l24 site:hybridz.org" results in this post:

Lots of good information in there.  Good Luck!!!!

 

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250 hp out of 2.8 liter L series is a pretty lofty goal that will require a lot of head work and assembly detail that only a few shops have demonstrated.  Rebello, Datsun Spirit both come to mind.  I had a Rebello 3.0 bottom end and a local shop ported and heavily modified (welded chambers, bigger valves etc.) my head and I just broke 200 hp at the wheels.  I ran 11.5:1 compression with an Isky 490/290 cam  and had to constantly mix race fuel and pump gas which is a royal PITA!  Sadly a valve seat failed 2 years ago in that engine so I decided to go with an LS1/T56 swap and holy crap is that fun!  397 hp at the rear wheels, pump gas, instant torque, no fussy cold start procedures ....

Any way, as stated above, all the info you need is here at your fingertips.  Keep in mind that a 250 hp L28 is a fairly high strung motor ...a 350 hp l28 is definitely high strung a possibly not very street friendly.

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Then there’s the theory of relativity !

How much HP do you have now at the rear wheels ? Have you ridden in a 250 HP Datsun? How did you come up with your desired numbers ? 

Have you ridden in a 150 RWHP 240z with some good gearing ?

Striving for goals that are just numbers with out relativity ?

My car is dyno’d 155 at the rear wheels. Is it fast -not really - compared to today’s numbers. Quick and fun - yes by any standard. 

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Welcome! Looks like you've got a nice Z to play with.

 

As the others, I'm going to question the goals first. I can understand the street/track car goal but the other two seem more like requirements rather than goals. The 250-350hp is a requirement in order for you to achieve something. That something might be a certain lap time around a track, or a quarter mile time, or bragging rights at car shows, etc.

 

The more bizarre goal is the highly-specific compression ratio. Why is that a goal?

 

To figure out your start and end points, it's going to take a lot of sifting through info online. Some of the info is good but most is iffy at best. What the sifting absolutely will do is improve your search-fu and show you other things you should be searching for. Once you've wrapped your head around what it is you're doing, it'll take some iteration to figure things out on your own. This requires a willingness to spend extra time and money that you didn't anticipate spending and forego some instant gratification. It's never perfect the first time.

 

I'll link you to my build thread at the bottom of this post. The work I've done to my current Z represents what I've learned by hanging around Z forums and Z folks the last 11 years, doing some learning on my own, and working with other talented people. Engine-wise, it's a somewhat basic L28 build that made 195whp which is worth approximately 234hp at the crank on that specific dyno. The thread is a complete build log and as good a starting point as any to figuring out what it is you want and need.

 

Ross's advice above is bang-on. I will contend with one point, my engine ended up at 11:1 (not a goal but a result based on my requirements) and I run it on California 91oct at 35 degrees of timing advance without issue. ;) 

 

http://forums.hybridz.org/topic/111062-leons-other-260z/

 

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1 hour ago, Leon said:

 I will contend with one point, my engine ended up at 11:1 (not a goal but a result based on my requirements) and I run it on California 91oct at 35 degrees of timing advance without issue. ;) 

 

That's good to know! 

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Welcome.

 

The answers to your questions will be found in the various forums.

 

Suggestions:

 

  • Buy books/manuals for the engine and transmission you want to use.
  • Download a Factory Service Manual (FSM).
  • Download electrical schematics for your car.  PDFs are easier to read than those found in books. Some are in color.
  • Buy the book How to Restore Your Datsun Z Car by Wick Humble. It will save you hours of searching for "how to" info.
  • Focus on searching Hybridz as 99% of questions have already been addressed.
  • Make a detailed plan with parts list including cost before starting a project. Plan and cost out every system of the car.
  • Start bookmarking Z car parts suppliers - there are many!
  • Remember these are 40 year old cars and will need restoration to be safe and drivable.
  • Join ClassicZCars.com website and search there as well.
  • Become well informed about modifications before asking questions. People will be more inclined to answer informed questions.
  • Search the forums.
  • Have some money. I stopped counting after $12k.
  • Read the new member FAQs.
  • If you are unfamiliar with SU carbs, go to Ztherapy and buy the video "Just SUs".
  • Recommend that you drive your car stock for  awhile.  Do basic maintenance:  brakes, suspension, electrical etc. so you have a ready to drive platform when you finish the engine upgardes. You will be amazed by the improvement in performance by installing new stiffer shocks/springs, poly urethane bushings all around etc.  You will learn a lot about auto mechanics and how the Z car functions as well.

 

 Useful Links:

http://zhome.com/

http://www.classiczc...com/index.html/

http://www.zcarparts.com/

http://www.arizonazcar.com/

http://www.jagsthatrun.com/index.html

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I'm surprised that no one has warned the OP about California Datsun. I've never personally used them, and never will. From all the negative feedback on various forums this is a company to avoid like the plague. Particularly with any rebuilt engines or cylinder heads.  The fact that they have often changed their names is a big Red Flag to me. 

 

I do some more research before buying anything there. Too many negative reports for my comfort...

 

Rebello, Datsun Spirit and some other companies consistently get excellent reviews. 

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On ‎8‎/‎5‎/‎2018 at 6:33 AM, rossman said:

That seems high but I haven't priced an engine build since 2008.  For reference, my Rebello (Google it) built long block wasn't much more than $5K back in 2008 for a long block build with forged internals, custom cam and mildly ported head.  You can do the math.  I'd recommend shopping around, and be sure to read about HZ member experiences with California Datsun.  I believe they used to be called Datsun Parts.

I have checked out Rebello before. I was attempting to keep this build local, hence why I had a shop near me quote a rebuild. I also thought the quote was high. Thank you, I didn't know California Datsun was originally Datsun Parts LLC. I don't think that I will be buying from them anytime soon, given their reputation on the forums.

 

On ‎8‎/‎5‎/‎2018 at 6:33 AM, rossman said:

Talk to Rebello Racing (or read more HZ) and get ready to open your wallet. You won't be able to run pump gas with that kind of compression.

Are you sure. I have read several posts on this forum and others that you could run 93 pump gas with 10:1 up to 12:1. Obviously not everything I read is reliable and my lack of knowledge is no help. Is there a reason why you don't believe that I could run pump gas on 11:1 Comp?

 

On ‎8‎/‎5‎/‎2018 at 6:33 AM, rossman said:

I certainly don't have the time or will to spoon feed information maybe some other nice soul will

I certainly don't expect you to "spoon feed me information" I felt my questions were relatively narrow. And any starting point advice you would be willing to give me would be very helpful. Regardless you certainly don't have to answer to my thread. But thanks anyways.

 

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On ‎8‎/‎5‎/‎2018 at 7:38 AM, 30 ounce said:

 Keep in mind that a 250 hp L28 is a fairly high strung motor ...a 350 hp l28 is definitely high strung

I guess I didn't think that 250 hp was a high strung goal. I set that as my goal based on what I have read from other forum members and what sites like Rebello and Datsun Spirit are suggesting you could get out of an L28. And I artificially set the 350 hp number as just a range limit.

On ‎8‎/‎5‎/‎2018 at 8:10 AM, madkaw said:

Then there’s the theory of relativity !

I fully understand that these numbers (250HP) were artificially set and based roughly on numbers that I have seen from other forum members / L series engine builders as I have no real experience in what a 250 hp Datsun is like. Nonetheless, it's a goal that I have set. If I happen to reach 200, 220 or 240 at the end of all of this, I'll be okay with that. It's merely goal to strive for.

 

23 hours ago, Leon said:

Welcome! Looks like you've got a nice Z to play with.

 

As the others, I'm going to question the goals first. I can understand the street/track car goal but the other two seem more like requirements rather than goals. The 250-350hp is a requirement in order for you to achieve something. That something might be a certain lap time around a track, or a quarter mile time, or bragging rights at car shows, etc.

First off thank you Leon! I fully understand questioning the goals, although to say that they are requirements is odd and I don't think I follow. Maybe my replies to the comments above clear up why I set that as a goal? Let me know if I'm missing something.  Also thank you for the link to your build. Ill definitely shift through all the information there.

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20 hours ago, Miles said:

Welcome.

 

The answers to your questions will be found in the various forums.

 

Suggestions:

 

  • Buy books/manuals for the engine and transmission you want to use.
  • Download a Factory Service Manual (FSM).
  • Download electrical schematics for your car.  PDFs are easier to read than those found in books. Some are in color.
  • Buy the book How to Restore Your Datsun Z Car by Wick Humble. It will save you hours of searching for "how to" info.
  • Focus on searching Hybridz as 99% of questions have already been addressed.
  • Make a detailed plan with parts list including cost before starting a project. Plan and cost out every system of the car.
  • Start bookmarking Z car parts suppliers - there are many!
  • Remember these are 40 year old cars and will need restoration to be safe and drivable.
  • Join ClassicZCars.com website and search there as well.
  • Become well informed about modifications before asking questions. People will be more inclined to answer informed questions.
  • Search the forums.
  • Have some money. I stopped counting after $12k.
  • Read the new member FAQs.
  • If you are unfamiliar with SU carbs, go to Ztherapy and buy the video "Just SUs".
  • Recommend that you drive your car stock for  awhile.  Do basic maintenance:  brakes, suspension, electrical etc. so you have a ready to drive platform when you finish the engine upgardes. You will be amazed by the improvement in performance by installing new stiffer shocks/springs, poly urethane bushings all around etc.  You will learn a lot about auto mechanics and how the Z car functions as well.

 

 Useful Links:

http://zhome.com/

http://www.classiczc...com/index.html/

http://www.zcarparts.com/

http://www.arizonazcar.com/

http://www.jagsthatrun.com/index.html

Thank you Miles for the suggestions. I actually have the FSM in really good condition and have been reading through it. I have been bookmarking forums snipping certain section that will hopefully be useful. Obviously the forums have a lot of information and it makes things daunting, thus the original post. But I appreciate the input.

 

5 hours ago, Chickenman said:

I'm surprised that no one has warned the OP about California Datsun. I've never personally used them, and never will. From all the negative feedback on various forums this is a company to avoid like the plague. Particularly with any rebuilt engines or cylinder heads.  The fact that they have often changed their names is a big Red Flag to me. 

 

I do some more research before buying anything there. Too many negative reports for my comfort...

 

Rebello, Datsun Spirit and some other companies consistently get excellent reviews. 

Thank you for the heads up! I have since done some research into reviews of the company and don't think I will be buying from them anytime soon.

I have certainly heard and checked out Rebello's and Datsun Spirits websites before and will most likely be purchasing through them.

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My 3.0 liter was right about 240 at the crank.  It can definitely be done.  The combustion chamber design of the L series heads are 1968-1978 designs and most were made to meet exhaust emissions of that era.  Today heads can incorporate high quench design which will reduce the pre ignition problems of those old open chamber designs.  I had my head's combustion chambers welded and reshaped to match more modern designs.  The cam also plays a huge role in how much compression you can run.  The later the intake valve closes after BDC the less effective compression you will have.  I have read several places that running 9.0-9.5:1 and running a full 35 degrees advance is just as good and more pump friendly than higher compression. Again, cam specs and compression ratios go hand and hand.  The only reason i did 11.5:1 is because that's what Ron Isky recommended and it worked.  It would run ok on 93 octane at my 5000 foot elevation but the gas station that sold it in my area quit selling it...so I had to mix race gas and pump gas...PITA.  If your going to have Rebello or Datsun Spirit build it then I'd listen to their recommendations.  My dad just had Datsun Spirit do his L28 and it's pretty awesome. It is fairly high strung but there is not a better sound than a hot L28 at full song.

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40 minutes ago, 30 ounce said:

My 3.0 liter was right about 240 at the crank.  It can definitely be done.  The combustion chamber design of the L series heads are 1968-1978 designs and most were made to meet exhaust emissions of that era.  Today heads can incorporate high quench design which will reduce the pre ignition problems of those old open chamber designs.  I had my head's combustion chambers welded and reshaped to match more modern designs.  The cam also plays a huge role in how much compression you can run.  The later the intake valve closes after BDC the less effective compression you will have.  I have read several places that running 9.0-9.5:1 and running a full 35 degrees advance is just as good and more pump friendly than higher compression. Again, cam specs and compression ratios go hand and hand.  The only reason i did 11.5:1 is because that's what Ron Isky recommended and it worked.  It would run ok on 93 octane at my 5000 foot elevation but the gas station that sold it in my area quit selling it...so I had to mix race gas and pump gas...PITA.  If your going to have Rebello or Datsun Spirit build it then I'd listen to their recommendations.  My dad just had Datsun Spirit do his L28 and it's pretty awesome. It is fairly high strung but there is not a better sound than a hot L28 at full song.

One thing you need to keep in mind that at a mile in elevation, your 240hp is going to be closer to 300 at sea level. My understanding is that 250hp isn't really a high strung motor (by my standard of high strung), or particularly difficult to achieve, especially today.

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14 minutes ago, rturbo 930 said:

One thing you need to keep in mind that at a mile in elevation, your 240hp is going to be closer to 300 at sea level. My understanding is that 250hp isn't really a high strung motor (by my standard of high strung), or particularly difficult to achieve, especially today.

It was SAE corrected for elevation so it should be 240 at sea level.  I’ve heard that this dyno is a bit stingy with the numbers but my LS1 swap with forged internals ported heads and FAST 92 intake dynoed on the same dyno at 397hp.  I expected about 25 more but at the end of the day it’s just a number and really only comparable to other runs on the same dyno.

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Just do an RB25DET swap, it will cost as much or more to build a L-series stroker and put high performance parts on it.  With the RB, you will get reliable performance and you can always turn up the boost.  Plus,  you keep the Nissan family straight six

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9 minutes ago, Samurai7one said:

Just do an RB25DET swap, it will cost as much or more to build a L-series stroker and put high performance parts on it.  With the RB, you will get reliable performance and you can always turn up the boost.  Plus,  you keep the Nissan family straight six

 

NO, RB would be my last choice. It's a 73, it's going to stay an NA L series like it was meant to be.

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 Don’t over look that L24 for a fun ride. Glad to hear others are staying true to Nissan NA ! 

Though Hybridz is an excellent site, don’t overlook CZCC. 

come up with a proposal of your specific build and guys here will help tweak it.

As far a relativity , my L24 stays keeps my car just ahead of my sons BRZ, so 50 more HP should be real fun. 

 

 

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Absolutely, anything else just feels wrong. What is CZCC short for? My search results came back with some odd sites lol.

I'll probably be making another post and laying out an actual build idea. And seeing what people say about that rather than what I started with here. I've noticed the wealth of information is incredible.

So I tried to keep my L24, but I live in Minneapolis and it doesn't seem any shops know a whole lot about rebuilding an L series other than a quote of $5000 for a stock rebuild. So, if I could find someone who would that was also close to me. I'd definitely try to keep the L24.

 

Also nice car. Sounds great.

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CZCC = classiczcars.com

 

Good on ya for sticking with an L series. Too many people ditch them for something else because they assume it's a bad motor because it's old. Or that they have to have 600hp to have fun with the car. Foolish.

 

What about doing a stock rebuild yourself on the L24, and getting an L28 to send out for a performance build? That way you can stow away the stock, matching numbers L24 in case you, or another owner, ever decide to put the car back to bone stock original.

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I'll check out that other forums!

 

Thanks. I've noticed, especially with the L24. People just throw it out the door. And I can't count how many threads I read where someone was building one. And every comment was to abandon the L24 and their build ideas. Seems everyone is stuck on needing to go turbo.

 

Yeah, so that was kind of the idea. I think I'll probably go with an L28 built by Datsun Spirit and after I get that all sorted out. I'll probably do a stock rebuild on the L24 in my garage as a learning tool. And then keep it stored away.

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So are you planning on doing any of your engine work or just contracting that out?

Displacement and rpms are king with NA, so most move on from the L24 unless restricted by rules of racing or something . Or your like me and you what to learn and practice on your 24 before you spend bigger money on a 28! 

I am currently building a L28 and have a stroker by Rebello in the works. Hopefully I make most of my mistakes on the 24 before I get to the 3.2

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Yes, there is nothing like the sound of an N/A L28, I just love it.  But I went turbo because it was bolt in and no internal work needed.  Still sounds nice, and the torque of the turbo helps me get over my lack of cash and engine building skills. 

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