Valve cover differences

[HS30-H]

Alan/Carl others can anyone shed some light on the Mercedes comment - I know it has been discussed before but I have been told that Nissan paid Mercedes a license fee much like Mikuni did when it licensed its carb technology from Solex..........

As far as I understand it, the truth is that PMC ( Prince Motor Co. ) licensed some Mercedes-patented design details ( not a whole engine design ) for their 'G7' engine - which debuted in June 1963.

Hiroshi Iida and his team at Nissan designed the new 'L-gata' engine 'module' during 1964 as a direct response to arch-competitor Toyota's new 'M' series OHC sixes. Iida himself admits to having been influenced by the Mercedes engine design, and says that they used this as a "reference". However, they did not license any Mercedes patents......

I think it would be fair for us to expect Iida san and his team to have been influenced by the Prince 'G7' engine design details ( even if he is too proud to admit it ), but Prince was not merged with Nissan until well after the Nissan 'L-gata' engine module was designed and in production. There was no direct 'inheritance' of Mercedes-licensed patents transferring from Prince to Nissan in relation to the 'L-gata' module.

We quite often see the history of the Nissan engine reported as a smooth sequence along the lines of 'Mercedes patents to Prince, and Prince taken over by Nissan' - but this is well wide of the mark. The situation was far more complex than that.

Has anyone else heard that an RB torque plate can be bolted onto a L6 block? I have been told that if your engine builder does not have a torque plate for your L6 boring then ask them if they an RB unit as it will work also :surprised

When Dr Shinichiro Sakurai and his largely ex-Prince team at Nissan were designing the new 'RB' engine module during 1982 & 1983, they purposely used the bore spacing and head bolt pattern of the 'L' series engine as part of the design. Sakurai has been quoted as saying that they wanted the 'RB' to be a worthy successor to the long and diverse history of the 'L' series. Higher management were pushing Sakurai and his team to drop the straight six and concentrate solely on 'V' configurations, but Sakurai and many of his team wanted to preserve the Prince / Nissan straight six lineage and history, and keep the straight six layout for the Skyline and Laurel models in particular.

We can draw many parallels between the 'RB' module and the 'L' module. Both of them were designed specifically to accommodate both long and short strokes, and small and large bore sizings. Both were designed to accommodate the possibility of 'high' performance and more sedate uses.

So yes, an RB torque plate can be used on an 'L' series six - and it is not just a happy accident.

Alan T.

[daddz]

Alan,

Thanks for clearing the air with regard to the L-series engine design. I am curious to know more. Where would one find information regarding the design history of the L-series engines as well as the RB-series engines?

[HS30-H]

I am curious to know more. Where would one find information regarding the design history of the L-series engines as well as the RB-series engines?

Hi daddz,

I'm afraid the best sources of information about such subjects are almost always written in Japanese.......

There have been a number of good articles on the L-series engine published in 'Nostalgic Hero' since it was first launched. 'Old Timer' magazine has had some good articles too. There was a really good one in 'Car' magazine a few years back, and there have also been a couple of good books covering the subject too.

Period Japanese magazine and press articles from the Sixties and Seventies are also a good source ( I have quoted from them in this thread ) and give a nice glimpse of the zeitgeist of the times. Japanese car magazines of that period were ( I find ) quite intellectual, and covered subjects in great depth. Publications such as 'Car Graphic', 'Motor Fan', 'Play Drive', 'Auto Technic'. 'Autosport', 'Motor Magazine' etc etc are a mine of useful and interesting data.

As for the 'RB' engine - well, we are talking about the mid 1980s here and articles from contemporary books on the Skyline range in particular are a great source, but so are most of the mags mentioned above.

To be honest, you have to collect a lot of reference material and piece it together for yourself. That means getting accurate technical translations too I'm afraid.

If all that seems like too much bother, you could always take the option of believing that 'Year Zero' for Nissan's L-series engines was when Katayama 'designed' the L16 over the telephone, and that the L24 was just an L16 with two extra pots. It certainly saves a whole lot of hard work.........

Oh yeah, and then there's this kind of attitude to contend with:

I will say up front that I do not believe that just because a magazine article or book is written in Japanese, or written by a Japanese writer - it somehow is to be given more credence than anything written English.I think we both have enough experience in that regard to know how badly mangled an interview or writing can get before it gets to print. I know that you and I can read the same article and come away with completely different perspectives of what was written.

Secondly, since neither I not the vast majority of our fellow forum members can read the Japanese sources you site as references - to decide for themselves the true quality, content and meaning of the wittings in total.. I can't really respond to your interpretation or possible misinterpretation of them. if you read your source materials like you read my Posts... well....

So remember, be careful not to misinterpret the "quality, content and meaning" of those Japanese "wittings"...... :classic:

Alan T.

[NZeder]

Alan,

Thanks for info on the Mercedes-patented design/License. I thought it was interesting how the RB torque plate was the same - that info helps explain why. It was a shame Nissan dropped the IL6 (In-Line 6) as no doubt a lot of Skyline enthusiast will agree that the current Skyline R35, with the V6 is just not the same as the R34 and those before it.

Just a personal thing I guess but I do love the sound of a IL6 on song. I guess this is why I like S30 family of cars, even Dad's L20aE powered Fairlady (now that it has my old headers and exhaust on) sound great.

Shame Dr Shinichiro Sakurai and his team did not make it so we could put an RB head on the our L6 bottom ends water and oil paths the same also

[daddz]

Alan,

Thanks for the response. My next mountain to climb is learning to read and write Japanese although this promises to be a long road as there are three(?) alphabets. My Japanese history course is winding down and it has proven to be a real charmer (about 400pp of reading per week as of late) and it has sparked yet more interest so now it makes sense to learn the language.

While reading this thread it came to mind the design of the LY28 engine (cylinder head)? Have you any information on the history of this unique variation on the L-series. A Japanese friend of mine recently allowed me to see some pictures that he took of a rare Silvia (S11) Rally car that maybe only four or so were produced and if I recall they too used the LY type cylinder head?

Thanks as always.

[HS30-H]

Thanks for the response. My next mountain to climb is learning to read and write Japanese although this promises to be a long road as there are three(?) alphabets.

Learning Japanese is a lifetime's work - even for the Japanese. One of the doubtful joys being that - even if you become fairly proficient at spoken Japanese - you will always come across Japanese people who tell you that you don't really understand what you are saying, "because you are not Japanese......".

I've never tried saying that about the English language - but one day I might. :hurt:

While reading this thread it came to mind the design of the LY28 engine (cylinder head)? Have you any information on the history of this unique variation on the L-series. A Japanese friend of mine recently allowed me to see some pictures that he took of a rare Silvia (S11) Rally car that maybe only four or so were produced and if I recall they too used the LY type cylinder head?

No, the 'LY' was never fitted to a Works car other than the S30-series Z. I wonder if you are getting it confused with the FJ24 engine that was used in the BS110 '240RS' model?

I have a fair bit of 'LY'-specific information and data, and it would probably be easier to send this direct to you rather than add it to this thread - which started out talking about rocker covers, and grew like topsy.

Alan T.

[sakijo]

Learning Japanese is a lifetime's work - even for the Japanese. One of the doubtful joys being that - even if you become fairly proficient at spoken Japanese - you will always come across Japanese people who tell you that you don't really understand what you are saying, "because you are not Japanese......".

Alan T.

Oh Alan, how true! Even I have been told that . . . . and I'm Japanese . . . Japanese-American, that is . . . . Ha Ha Ha. . . . .

[daddz]

Learning Japanese is a lifetime's work - even for the Japanese. One of the doubtful joys being that - even if you become fairly proficient at spoken Japanese - you will always come across Japanese people who tell you that you don't really understand what you are saying, "because you are not Japanese......".

I've never tried saying that about the English language - but one day I might. :hurt:

No, the 'LY' was never fitted to a Works car other than the S30-series Z. I wonder if you are getting it confused with the FJ24 engine that was used in the BS110 '240RS' model?

I have a fair bit of 'LY'-specific information and data, and it would probably be easier to send this direct to you rather than add it to this thread - which started out talking about rocker covers, and grew like topsy.

Alan T.

Too funny regarding the language comment. I wouldn't dare try that statement here in the United States. :surprised

In fact I was getting the 'LY' confused with the FJ24 engine as used in the BS110 '240RS' model. I think I meant to say that there is a four cylinder engine (possibly the LZ series) which has a valve cover similar in design to the LY's and as it was told to me was designed by the same person?

I am not sure if you can confirm that or not but nonetheless it would be interesting to know.

[Mr Camouflage]

According to a heated discussion going on in a thread about someones 240K, one of the members there states that there was a L6 DATSUN OHC valve cover:

Part number 13264-E3100 is a DATSUN cam cover for an L24. Part number 13264-P0100 is a NISSAN cam cover for an L24 or L26. At least that was what they were when I had to replace a cover back in '72 after a cam gear bolt came loose (and initially got the wrong, E3100, cover).

Can anybody verify this via the parts cd, or microfiche etc?

[Go240Zags]

I saw a JDM (aftermarket I think) cover with the Large block lettered NISSAN. But this cover was plastic. Les Cannaday had it in his shop and was very excited over it. As to why he was so jazzed, I didn't catch the story.

Was the plastic valve cover like this one Victor?

http://cgi.ebay.com/ebaymotors/Datsun-240Z-260Z-280Z-ZX-JDM-Valve-Cover-NR_W0QQitemZ250057883925QQihZ015QQcategoryZ33627QQrdZ1QQcmdZViewItem

[red_dog007]

Was the plastic valve cover like this one Victor?

http://cgi.ebay.com/ebaymotors/Datsun-240Z-260Z-280Z-ZX-JDM-Valve-Cover-NR_W0QQitemZ250057883925QQihZ015QQcategoryZ33627QQrdZ1QQcmdZViewItem

Is there any advantage to getting one of those for a L24 block, or is that something mainly just for looks?

[sblake01]

The only advantage would go to the seller as he puts the buyers money in his pocket.