DOHC head for an L-series.

[Azon]

I heard somewhere that there were DOHC heads produced for the L-series engines by some aftermarket manufacturer. Does anyone have any more information on those heads? Were there ever factory (eg factory racing team's) DOHC heads?

[lambs]

OS-Giken made aftermarket DOHC 4 valve/cyl heads for L4 and L6:

 

http://www.datrats.com.au/OS%20GIKEN%20ENGINES.htm

 

There was a rumour of an OS-Giken DOHC L6 head residing in WA, but just a runour.

 

Nissan made twin cam heads for L4 engines:

 

http://www.datrats.com.au/lz_twin_cams.htm

 

But not for L6 although it would be reasonable to think they had them in prototype form at some stage, remembering that the Prince car company developed the S20 DOHC 6cyl used in the Z432 (ie they had the technology).

[Azon]

OS-Giken made aftermarket DOHC 4 valve/cyl heads for L4 and L6:

 

http://www.datrats.com.au/OS%20GIKEN%20ENGINES.htm

 

There was a rumour of an OS-Giken DOHC L6 head residing in WA' date=' but just a runour.

 

Nissan made twin cam heads for L4 engines:

 

http://www.datrats.com.au/lz_twin_cams.htm

 

But not for L6 although it would be reasonable to think they had them in prototype form at some stage, remembering that the Prince car company developed the S20 DOHC 6cyl used in the Z432 (ie they had the technology).[/quote']

 

Thanks for this - exactly the answer I was looking for.

[JBWetzels]

Any info on the L6 DOHC Head?

[Huw]

all i know is it was made, in japan by OS Giken and that it costs a bloody large amount of money (had a look a while back) can't remember where, sorry.

 

Huw

[zr240]

Alot of us have looked into the dohc L series and it just isnt worth the money. Last thing I heard the head would set you back at least $10,000 so you are better of buying a RB 25 for $1000-$2000 and if you want the old skool look and sound you can get a manifold and bolt on triple webbers.

 

If you wanted to do it on the cheep you could even use the RB20 and then it woulb be the same as the original L series twincam that came in the 432

 

Ash

[lambs]

If you wanted to do it on the cheep you could even use the RB20 and then it woulb be the same as the original L series twincam that came in the 432

 

The S20 engine used in the Z432 is not an L-series engine. It was an entirely Prince company design, which Nissan acquired at the time the companies merged.

[NZeder]

If you wanted to do it on the cheep you could even use the RB20 and then it woulb be the same as the original L series twincam that came in the 432

 

The S20 engine used in the Z432 is not an L-series engine. It was an entirely Prince company design' date=' which Nissan acquired at the time the companies merged.[/quote']

 

If you want a close engine from Nissan then it is the FJ20 that you will be looking for as this design was taken from the S20 (as lambs has stated a Prince design). So other than the S20 there is no other period correct DOHC. Re the OS Giken DOHC for the L6 bottom ends. I believe they were cast using a wooden mold the first casting were the best as they were stonger units. They later changed the casting to keep the costs down (I believe) however these were not a strong and as such most have been killed on the track (bent/warp etc). The last I heard is that there were 3 of the original casting heads still around in cars in Japan however the owners will not part with them so unless you are planning on making your own DOHC I think you will be out of luck (or a lot of coin if you could convince someone to sell theirs.....would you?)

 

Having said all this I believe a RBxx torque plate can be used on the old L6 bottom ends when doing a over bore....hmm how much water and oil galleries need moving etc - anyone looked in to this? I have not seen a RB head off so I can't tell you anymore than the above.

[JBWetzels]

hardly sounds worth bang for buck

[DevZed]

i heard that they recently made 10 more heads at a cost of 30k each. this has become a bit of folklore hasn't it

 

if you want to see one of the original heads in action look up Office Tomitaku on youtube

[C.A.R.]

Holy Thread Revival, Robin!

Did you know the Titanic sunk as well?!

[d3c0y]

Quick delete it Lurch!

[dat2kman]

I know of and have seen, two cylinder heads from S20, one on a shelf, and one just lying on the floor, of a old school Datsun specialist, in Japan.

He may sell, but are you prepared to just say "Ai" to his price?

He knows their worth.

It'd be in the millions of yen, as a starter.

 

Also in existence for L engine is LZ18 ( 4 cyl), used in Violet 710, Auster/Stanza PA10, in Nissan rally program only, and a odd on, LY28, not a twincam, but a crossflow, have photos of Z car, was raced in Japan Domestic in mid 1970's

 

To go this route, is too hard, just go RB, make rocker cover look "old"

 

A guy name of Warwick Williams has biult a replice 250F Maserati, circa 1960's, stuck a atmo RB on triple Weber Carburatori induction, and somehow has removed the Nissan RB casting off the rocker cover, and cast in, in traditional script, " Maserati"

Excellent replica, only issue, he used SHS instead of round for the tube chassis, DOH!!!

[DevZed]

hehehe success

[Six_Shooter]

What I find entertaining is how much a lot of these "rare" and "limited production" parts are "worth so much", yet I never actually hear of any of these parts changing hands, mostly due to price being more than it's worth, so that really begs the question, What are they really worth? 

 

I've seen it time and time again, someone thinks some item is worth X amount of money, but no one is actually willing to pay that much, which really forces the idea of an item being worth less than what people would like to believe they are worth. Something is only worth as much as someone is willing to pay for it.

[dat2kman]

Any idea or clue as to how much the last Z432 sold for in Japan??

I'd warrant none on this antipodean forum would have even known one came up for sale!

The market in those is a "closed shop" ie those in the know get to do deals.

 

As i have "connections"  with FJ24 and Nissan 240RS rally cars, i have been offered whole cars, and rare parts, they are priced accordingly, due to rarity, i dont think pricing is ridiculous.

 

I am aware of other things like FIA option cylinder heads, Option gearboxes etc, Sumitomo MK63 calipers, vented discs, for original Z, all quite hard to source, but for purists they are desirable items. I heve two different Option gearboxes for sale, at aroubd $3k each!

But a non purist can cobble together something that is close to one, at a bit less cost, why not, cos' nowadays some things are possible!

[d3c0y]

There are 432s for sale at dealerships over in Japan, those and KPGC10s sell for around $100,000k

 

Dat2kman is right most people on this forum think that $1K for a ported head is too expensive.

It's all relative as they say and in the racing world these rare parts can give a big advantage and there are hardly any around. How much do you think parts are for for ever limited run sports cars like F40s are?