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Interesting clip. Too bad there's not another one available that illustrates the flow around the back of the car, where the other half of the Z's issues reside (front-end lift being the issue at the front). I spent almost 15 years of my engineering career with a Canadian company that was one of the four world leaders in wind tunnel design in the day (the others were Sverdrup in the USA, TLT in Europe, and Meidensha in Japan). For reference, my company (DSMA International -- now reborn as Aiolos Engineering) designed and built the Porsche wind tunnel in Weissach back in the late 1980's and later designed the Williams Grand Prix Engineering wind tunnel in the early 1990's. We also worked for Volvo, SAAB, Honda, Ford USA and Europe, GM, Chrysler, Hyundai, BL Cars, as well as for clients in the aerospace and fuel/lubricants sectors. Those were interesting days. The picture of the old Nissan wind tunnel shows a rather old-fashioned design (even for its time) with an open circuit layout (affects efficiency), a small test room cross-section (affects accuracy), and the absence of an in-floor measurement 'balance' (floor/ground effect ignored, yaw measurements complicated or ignored). In terms of absolute accuracy for Cd measurements, it probably couldn't do much better than +/- 3 to 4 %. By contrast, a modern tunnel delivers +/- 1% or less. Nissan replaced this tunnel with a much larger and more capable, closed-return circuit design sometime in the late 1970's or early 1980's (it was in place and operational when I visited circa 1988). Production car aero development was in its infancy at the time when the Z was being designed. The oil embargoes in the early 1970's were what really made the industry get serious (Americans will remember the 55-mph national speed limit as another component of the 'energy crisis' days, while Nissan captured the spirit of the times with its marketing slogan, 'Datsun Saves'). There was major industry investment made in the acquisition of modern, high-accuracy/capability wind tunnels throughout the 1980's, as well as for accommodating the cost of aero test/development hours into new-model development budgets. It's all become pretty formulaic now, but that's because of all the ground-breaking work that was done in those new wind tunnels throughout the 1990's. I remember that one of the important issues that designers were trying to sort out was how to optimally locate and size the extractor vents to enable effective cabin air flow-through. As all of us Z owners know, this was something that Nissan hadn't really got a handle on when the Z was being developed!

Ya, not sure why it's posting the videos three times. Just copy-paste the single link and it should work only once. Maybe it's a bug, who knows. Just keep posting the videos and I can fix it... no need to worry about it.

Going through the various on-line FSM pdf files for the various years this morning, and sure enough, at least the 71 and 72 manuals list the "camshaft gear bolt" torque as 36-43 ft-lbs. The 73 manual if finally correct at 86-116 ft/lb Holy "engine destroyer" batman....

To think this all started with trying to figure out where my temp sensor hookup was, hah. Thanks to everyone for all the input, this has been hugely educational for me. No shims on the towers on the E88 head. Whats a good way to measure the head to see if it had been cut? Or would the lack of shims make that not a possibility Is that something that could be machined in there? Maybe farther down the road I'll have someone work on that head and swap it out. I think for now I'm going to roll with what I've got and focus energies/monies on getting this sucker on the road. Still have a looonnngg way to go

Have a look at this video: wind_tunnel_2.mp4

It looks big enough, and "state of the art" enough, to me. 1969:

Not really sure how this thread went Star Trek, but I will play along....... Remember Vina......

snorkel is in! no need for that bracket, its not going anywhere and besides I could not see where it bolts on to the core support anyway. Starting to wonder if the 75's had one? anyway it looks cool and its staying put. there is a vent that goes into the fender and no where else, so I always assumed it was supposed to be there. maybe there is a bolt hole I am missing, its kinda dark out in the garage.

Or paint the bay orange. Come on man, you're smarter than this!

The answer is in your picture.

Earliest engine manual "Model L24 L20A Series Engine" has error in photo but correct value in specification table. 5 to 6 kg-m is incorrect for both

I like the one where kirk was faking madness to get the Romulon cloaking device. Any time kirk freaks out is fun to watch.

Klingons

@jalexquijano Are you operating the choke in either full on or full off mode? Or are gradually easing the choke off as the engine warms? Either way, I'm not surprised that the engine didn't run optimally until it was fully warmed up. In the future, let's concentrate on symptoms that occur when the engine is fully warmed up. Any complaints when it's warm. Idling for a few minutes? # 4 plug looked the same as the others. We're making progress. @siteunseen Tick tock, tick tock.

Here's a link that seems to cover everything including a way to possibly get the wrong number. Looks like 108 mm is the number. Norm the 12 Second Dude was deep in to L series engines until he crashed his Z and sold it. http://www.zcar.com/forum/10-70-83-tech-discussion-forum/123994-stock-head-thickness.html

With the threat of the tribbles multiplying and filling the Enterprise, Scotty beamed them to the Klingon mother ship. Who knew?

Confirmed by an alternate source: Page 24 in How to Rebuild Your Nissan/Datsun OHC Engine by Tom Monroe states -- Torque the cam-sprocket bolt 86-116 ft-lb (12-16 kg-m).

Yes.. they look great. Sounds like you have an intermittent issue. Try running with each jet turned down an additional half turn and see if you like it better btw I did 180kph on that highway along the canal... you have the best test drive course of all of us! but that road is deadly at night.

I have more:)

mon traducteur était hors de la ville, quand j'ai écrit ceci s'il vous plaît pardonner l'inexactitude.

And even if the lack of fuel pumping was caused by the eccentric, there should still never be fuel leaking out the back of the fuel pump. So make sure you double check that pump before you consider it good.

You're a little early with your April 1st joke. Hopefully you won't get clipped by any passing traffic when you are messing about with your bonnet/hood stay. I mess with mine whilst I'm standing on the kerb.

I believe the bonnet (aka hood) stay on left is further evidence the S30 was designed for North America It goes back even before the first 432R that raced in Japan on Jan 18, 1970 (below) ,,, with triple Webers no less.

Does not matter.. videos are great! Thanks

Looks like that pump has a built in filter. High RPM weakness is either not enough fuel flow or your ignition failing.

Yes the high number is correct. Some blue loctite on that bolt and the two small bolts that hold the end plate on are recommended.

@Richard McDonel Glad to help and find that the issue is resolved for you Richard! Those Kyosan Denki mechanical pumps are very rugged and reliable---it just made no sense that one would go bad after sitting in a box and then only being run for 20 minutes or so. No--there's a story behind this------ Carl Stahlnecker (Bambikiller) was a respected member of this forum many years ago before his shockingly sudden death. I still dearly miss Carl. His numerous posts were among the most informative I have ever read. Carl really knew his stuff about Z cars and was always very helpful, but often opinionated and direct. His screen name--- Bambikiller--- came after an incident between his 240z and a deer. I ran over a frog one rainy night in my 240z and lamented the poor amphibian's demise. In homage to Carl I suppose, I chose "Frogsquisher" as an adjunct to my screen name Zup.

Oooo...! I’d like to be a fly on the wall for that! I’d even bring the entry fee!

@zKars Thanks Jim! I need to come see your shop...

Haven't seen that picture with the load sensors under the tires before. I'm guessing Nissan has a larger wind tunnel now. But it's interesting to see "state of the art" 1971. I've been in Porsche's previous Weissach wind tunnel and it was much larger. I think the new one is even bigger - good for everything from bicycles to vehicles larger than cars. Dennis

Who cruises at 5,000 rpm's? Pressure and flow are different!!!!! Pressure is not the issue!!!! The water going over Niagara falls has low pressure but lot's of flow... If you are running out of fuel it's a flow issue not pressure!

ZUP, Thank you! You get post of the day - no, the post of the month - award! Yes, I pulled off the valve cover, and there was the eccentric, spinning free. Should be problem solved, but I'm a little nervous about how it functions. The bolt is large - 14 mm - but the manual only calls for 40 ft.lbs. of torque, as compared to 60 ft.lbs. for the skinnier head bolts. I did what the book said, and used loc-tite. But I look at the overall setup and it occurs to me that the natural friction of the pump lever on the eccentric would tend to loosen, rather than secure the bolt. Anyone have any thoughts or experiences with that?

Ok, well.....got home from work and fired it up again. Sure enough the tapping came back after about a minute of running. Then after another minute or so and a few quick revs the tapping got really bad...so I shut it off. Pulled the valve cover and saw that now hte #4 valve was not up to it's full up position even though the lobe was not pushing down on it Got my bore scope out and looked in the spark plug hole and could see a fresh mark on the piston from the intake valve. Then went though the intake and can see that the valve seat came completely loose. Fack. So....that's my Thursday night. Going to think about how to proceed. Might wait and have my friend who is wrapping up an engine rebuild on my NSX have at it once he is done with that car in a couple weeks. He'll be able to comb over everything much better than I could and he's basically an NASA engineer when it comes to assembling and inspecting engines. Not the outcome I was hoping for but it is what it is. Not sure why the seat came loose in the first place, but it all makes a lot of sense now.

Oui!!!

C'est what?

That's only one beer from each brewery, lightweight!!!

Edit - apparently it is valve head diameter that you measure. It's not what I would want to know but it's what is done, apparently. So your valves are close to L28 size. Actually, it's hard to tell from the out edge measurements, which overlap the seat. I think that the number is actually the seat diameter. Where the flow happens. 1.74 and 1.375 are 44.196 and 34.925, so more likely 42 and 33, stock E88. A guess. Not large enough to be L28 though. I could be wrong. I forgot about the injector cutouts, so that's a consideration. I'd just get what's in there running well, drive the crap out of it and see if needs more of anything.

Working on them currently to fit with all S30s and S130s. I'd have said below the Street because of the short primary pipes but funnily enough, a rather knowledgeable man actually prefers them for a friends' L28, tripled engine build.

Facebook? What is that?

Celebrating 47 years together today. It did not start out as a "forever car", it just worked out that way.

Here's a couple pics of Nissan's newer design spray bar. The distribution blocks are made completely differently and are made out of steel. The whole thing is brazed together instead of trying to solder to aluminum. So I don't know when the new design went into effect, but I think it was 75 or 76. And as for finding one, I see them on ebay frequently, although I didn't check today.... From that old spray bar thread, a couple pics of the new design:

Let's get together for coffee, beer, food. What does your schedule look like?

@dutchzcarguy This is a good read on spray bars. The last page goes off the rails though, mostly because of me. Here's the one I was thinking of, a newer design. Here's the difference in between the early and later ones.

Good to hear you got it up and running. It's easy to under estimate how much air is in the system after stripping it down and cleaning it. Takes a while before it's all out and that can cause a lot of issues like hard to start and won't run. On the pressure: These early EFI systems don't meassure fuel pressure. The ECU calculates fuel delivery based on a constant fuel pressure over the injector tip. The pressure regulator is connected to the manifold to messure vacuum and adjust the fuel pressure accordingly. If you didn't regulate the fuel pressure: Say you had 10 in.Hg (-4.91psig) vacuum and didn't regulate the fuel pressure, you would have 40.91psig pressure across the tip and that would supply more fuel than the ECU calculated. The regulator would reduce the fuel pressure to an approximate 31psig. 28 psi is about right at idle. Depends on your vacuum in the manifold. It should have about -8psig or 16 to 17 in.Hg The CSV uses 12 volts. A 9 volt battery will activate it. I don't think 2 AA will activate is. I also use a 9 volt battery to test injectors. I have never burnt one out yet. Mmm now Ive said that..... In the circuit diagram you will see the CSV doesn't have a dropping resistor like the injectors. Your distributor drive might be a couple of teeth out of alignment. It might be easier for now to do what Zed Head said and rotate the plug leads one position on the distributor cap. Then you can set the distributor back to approximatly the correct position. I am wondering how it got so far out of position. Maybe the PO dismantled it and reassembled it and the engine has never run since. There is a thread hear talking about setting the distributor.

Road America IMSA

Mike, Here is the list of the bushing I purchased for my 240Z FRONT CNTRL ARM BUSH 54535-E4100 FRT TENSION ROD BUSH 54476-21000 FRT SWAY BAR END LINK BUSH 56112-W5000 FRT SWAY BAR TO FRAME BUSH 54617-21002 RACK BUSH/DRIVERS 54445-E4101 RACK BUSH/PASS 54444-E4101 FRONT STRUT BUMP STOP 54050-E4101 FRONT STRUT MOUNT 54320-E4100 REAR CONT ARM INNER BUSH(FRT) 55554-E4100 REAR CONT ARM INNER BUSH(REAR) 55555-E4100 REAR CONR ARM OUTER 55541-E4100 REAR CONR ARM OUTER SPINDLE 55540-N3701 REAR CONR ARM OUTER SPINDLE NUT 08912-8421A DIFF MOUNT 55415-E4102 REAR STRUT BUMP STOP 54050-E4101 REAR STRUT MOUNT 54320-E4100 MUSTACHE BAR BUSHING 55476-N4300 STEERING COLUMN COUPLER 48073-78500 It was very time consuming to locate all the parts, so be patient. Keith