HS30-H

The R190 was what Datsun Competition USA called the diff. that came on the PS30 ( Z432 ), PS30-SB ( Z432-R ), PGC10 ( Skyline GT-R ) and KPGC10 ( Skyline GT-R ). In Japan this was always known as the "R192". I have no idea why Datsun Competition decided to call it the "R190" - but there you go. Essentially its an R180 on steroids. It looks just about the same, but is bigger ( as its name implies ) but not as big as the R200. Just like the R180, they were full of shims and spacers, and take an age to set up properly. This R200 was a massive leap forward in this respect. As fitted to the Z432 and Z432-R, they came stock with an LSD and 4.44 gears. The PGC10 and KPGC10 Skylines usually had 3.9 gears. The moustache bar on the 432 was different to that on the R180-equipped cars. Parts for the R192 / "R190" are pretty expensive in Japan - especially the LSD units. Alan T.

Not very clear when you zoom in on the photo, but they look just like 50PHH MIKUNI SOLEX to me. Alan T.

Eric, I'll have to try to hunt down the original CarBoy magazine article ( I know its in my archive somewhere ). Bear with me while I hunt it down. Don't be too disappointed at how they got the 330ps out of it; this was back in the late Seventies / early Eighties as far as I remember -and I know that they used an unstreetably high compression ratio. The original engine and car it was installed in was a drag / street racer that I remember as having a suspension setup not very conducive to standing starts............. Let me look into it. I might need to e-mail you some photos or something. Regards, Alan T.

Yes, the LY28 was the "Crossflow" head offered by Nissan as a "Sports Option" part from around 1973 onwards. This was a single camshaft, two valve, hemispherical chambered crossflow design. As Yo2001 pointed out, the bellhousing for the transmission and the engine mounts were quite different because of the change in angle to the block. The correct pistons also needed to be used, and it was recommended that the Option crank and rod set was also installed. I've seen quite a few dismissive comments about this head / engine over the years ( especially in the Honsowetz book ) but I have to say that hearing one of these things on song is a sound for sore ears. They breathe really well, and produce good power. There are in fact a few cars running in Japan with them ( several on the street........ ) and NISMO restored one of their old 240ZR "test" cars for the 2001 NISMO FESTIVAL that used an LY28. It went really well. We also have a couple of 240's running this head here in the UK. One of them is a street car that does not get used all that often, and the other is an ex-Works Rally car. Might as well forget about trying to find one of these; the queue is already a mile long ( I've been waiting about 10 years already! ). When they change hands, its usually among acquaintances and for a LOT of money........ Alan T.

Hi Doug, First of all, do you know what it is? It's not a UK product - its made in Japan. A little bit of a "history lesson" might be of interest to you; The original pattern for these valve covers was developed by a Japanese company called KAKIMOTO RACING. They were a fairly small company that became well-known for a particularly powerful 3.1 litre L-series conversion that used the LD28 crank, L14 rods and Yamaha XL500 motorcycle pistons. One version of this was tested by Car Boy magazine and produced 330ps at the flywheel. This was back in the late Seventies / early Eighties. Most of the power came from the extremely high compression ratio and the very heavily re-worked ( extensively welded and reshaped ) head. Kakimoto made their own cams too. Mr Kakimoto did quite well selling engines and parts from this publicity, and one of the parts he went on to produce was his own valve cover. Although they were bigger than the standard L-series covers and had proper baffling and venting, it has to be said that the main benefit of the covers was visual. They promoted the company name and made an engine look rather more special than it might otherwise appear. The original Kakimoto version just had "KAKIMOTO" cast lengthways, and "3.1" across the front above the timing chain. When Kakimoto's agreement with the casting company ran out, other companies were able to use the same basic casting and put their own names on them. The cover on my car is one of these. It just says "DATSUN 3100" and "OHC" on the front. You can still get them in Japan - but you might find the price somewhat discouraging ( around 50,000 Yen retail ). I bought mine used in Japan - so it was considerably cheaper than that. I've had mixed reactions from people when they look at it. Interestingly, they either love it or hate it ( quite a few comments were surprisingly rude! ) but I put it on as a bit of fun, and don't take it too seriously. All the best, Alan T.

Glad you're all so impressed with it. You guys on HybridZ seem to like these turboed dinosaurs ( I'm more of an Old School lover ). I'll have to dig out some other pics from the past too ( seem to remember an LY28 "Crossflow" head with a single turbo conversion too ). Really busy with work at the moment - so not at the computer very often. Might take me a few days to hunt the pics out. Bear with me............... Sorry - don't remember any HP or performance figures off the top of my head for the Twin turboed O.S. Giken TC24-B1. I'll have to have a dig around in my archives and see what I can find on it. It was featured in a Japanese tuning magazine when it was first built - so maybe that might have reported some figures. Let me look into it. Ron - those turbines were KKK "K26-3664G" ( If I remember correctly they came from a Japanese truck ). They were blowing through three 50mm OER carburettors, and it also had 6 injectors in the inlet manifold which were controlled by an SK D-Fit injection unit. Best regards, Alan T.

You're all welcome. I'm pleased that you thought the pic was worth seeing. Bryan, I will send an e-mail direct to you. Rick, I think Cody is forwarding one to you direct - but I will send one to you anyway. Maybe if it can be put up here then it will save me firing off too many e-mails. Yasin, there is a relatively small following for the early Z cars here in the UK. This is mainly because not all that many were originally imported, and because the few thousand that were imported had a very high rate of attrition ( a long journey on a boat in a salty atmosphere followed by wet winters with road salt ). The later stuff ( especially S130 series ) suffered even worse, and the Z31 has never really been loved that much. The Z32 is now very cheap over here and there are a real lot of Japanese-market cars that have been privately imported. Personally, I'm into the S30-series. You are right about the UK motoring journalists, and they are STILL biased against old Japanese cars. They have to grudgingly give respect to the later high performance models, but they never seem to put them on the same level as stuff from Germany and Italy. Let me know if you come to the UK, as maybe I can give you some pointers and a look at my cars ( might interest you ). Bryan ( Dat240zg ) what do you drive? I have something here in London that you might be interested in ( judging by your sign-on name ). Regards, Alan T.

slownrusty, jeffp, cody, eric-z, Len168 & RonR - you all have mail. Hope you will all remember that this installation was from 1986 in the bad old days of Japanese street racing, when things got quite silly. Some of those cars did not last more than a few weekends of action before a complete revamp / rebuild. Len168 - I can't imagine O.S. Giken allowing anyone else access to their blueprints. I'm sure that they would want to protect their copyright too. Certainly can't blame them for that. Regards, Alan T.

Mudge, Yasin, Jeff and Cody - thanks for the responses. Thanks for the encouragement Mudge. Yasin, Jeff and Cody - I am scanning up some pictures of that twin-turboed TC24 to e-mail to you. Should have them through to you within the next 12 hours or so. I really hope Ron liberates that head and makes it live.................. Regards, Alan T.

Len168, I thought it was Mudge who made the "pimp value" remark, not you? Where I come from, the word "pimp" is a pejorative, so in my mind it kind of shows disrespect to what I think is a great piece of engineering from a company that was quite small but very brave when they made it. I feel like I should defend O.S. Giken against this. Someone needs to stick up for them! Those "$12,000" quotes from the Honsowetz book need to be put into perspective for both the Dollar / Yen exchange rate of the mid 1980's and the Japanese economy at that time. My personal experience of this conversion is that I have passengered in a car equipped with one, and was around a group of people in Japan who were using them. When I was living in Japan many years ago, I was involved with a group of people who worked in a tuning shop there. They used two of these heads in "company cars", and one of them was a 3 litre conversion used with a pair of KKK K26 turbos. That was quite an impressive car for 1986. Personally, my taste is more "old school" and I prefer old cars with carburettors - but it was fascinating to see the ingenuity and dedication of the tuners at that time. What they learned then stood them in good stead for when the RB26DETT came out in 1989. It could be argued that Nissan themselves learned a lot from the Japanese street tuning wars of the late 1980's, as they still continue to do. Some years back I was also involved in trying to persuade O.S. Giken to make another small production run of them, which they did not want to do. I don't blame them, as its doubtful that they made any profit at all from the original runs of either the 6 cylinder or 4 cylinder versions. They are doing very well with their current range of Clutches, Flywheels, Gear kits and Pistons. They also developed a 3-litre conversion for the RB26 engine, which I think was very brave. They are a much bigger company now than they were when they designed and developed the TC24-B1 and MA11 heads........ Len168, I think you might be interested to see a picture of that twin-turboed TC24 ( if you send me a PM with your e-mail address I can send some to you ). That was one crowded engine bay. I have often "dropped in" to the HybridZ site as a casual visitor, but Ron's original post prompted me to join up as a member. I thought it was a debate that I could contribute to with first-hand knowledge. If that is not welcome then I probably made a mistake by doing so. Sincerely, Alan T.

Those "4 - 6%" figures that Frank Honsowetz was writing about are in relation to the LY28 Crossflow head, which was a two-valve single cam hemispherical combustion-chambered design. The big advantage of this head was that it allowed reliability at much higher revs than the standard non-crossflow heads, and was well proven in Japanese domestic circuit racing and international rallying. The figures that he quotes are not accurate...... The O.S.Giken TC24-B1 twin cam crossflow head is another matter altogether. The negative comments above ( especially that "pimp value" comment ) are probably based on hearsay rather than first hand experience. This head conversion was very well engineered by a great company, and worked very well indeed. The main purpose of the TC24-B1 was to allow prolonged high rpm use with good breathing. This was achieved, and is well known in Japan amongst enthusiasts of the L-series engine. In theory, any twin cam four-valve crossflow design is going to be more efficient / desireable than a two valve non crossflow design. The fact that in practice the "normal" L-series engine does so well against such exotic conversions is testament to just how great the "normal" L-series engines are. Alan T.