Datsun-240z Vs Fairlady-z432

[kats]

Thank you Mike and Will,

Cutting panel is for accessing the areas where is hard to reach.This is the best way to have good result as much as they can.

kats

[Carl Beck]

Hello,

I am not for sure but I assume the pipe difference might cause the spoiling of the feeling of the S20 engine.What do you think?

Hi Kats:

Off hand, I do not believe that a smaller diameter output tube on the L20 tank, would by itself have an adverse effect on the triple carb set up on your S20.

A smaller output tube running from the tank to the electric fuel pump, combined with a fuel pump that was weak {or under performing} - could certainly adversely effect the performance of the S20.

The triple carb's need to be feed fuel to their fuel input line at 2.5 to 3 psi. The size of their {the carbs} fuel input , combined with the fuel pressure specified - determines the total volume of fuel needed to keep their float bowls full.

As long as the electric fuel pump at the tank, could provide enough fuel to keep the 432 fuel lines at the engine pressurized at 2.5 to 3 psi - - the engine should perform to specification.

If the electric fuel pump was not able to maintain a fuel line pressure of 2.5 to 3 psi - - then the S20 engine would not perform to spec.

Using a fuel line out of the tank to the fuel pump - one size smaller than needed would make the fuel pump work harder, but it should have been able to overcome the minor restriction and still supply enough volume to maintain the needed 2.5 to 3 psi - on the output side of the pump.

It is possible that the fuel pump simply did not have enough margin or performance range {ie it just wasn't strong enough} to supply the needed volume of fuel at full throttle.

Tthe only way you would know for sure if the pump was supplying enough fuel - is if you had a fuel pressure gauge in line with the carb's - that you could see while making a full throttle run. Second way of telling would have been to make a full throttle run with the car - then pull the spark plugs and see if they were indicating a lean mixture. Third way of telling would have been to install a wide-band CO2 probe in exhaust system - hooked to an Air/Fuel Meter.

At any rate it sounds like you have already solved the problem - even if we don't know for certain what caused it.

The pictures of the fuel tank are very interesting, and it looks like the shop did a great job. Thanks for sending them along. Interesting to see that the shop cut an access hole in the top of the tank, then welded it back up.

FWIW,

Carl B.

[26th-Z]

Thanks for the pictures from 4150 Kats. That is over the top! They will go in my picture collection of the car. I also have a huge collection of pictures from Zama. It is very nice to hear how well the cars are maintained.

To fit that big gas tank up into the body, the spare tire well was removed and the opening was covered with a flat plate. Spare tires were carried in the rear deck. If memory serves me right, all the PS30-SBs came this way? I wonder what the gas tank sending unit came from?

Edit: Oh yea, you said Z432-R has this gas tank.

Edited June 30, 2009 by 26th-Z

[HS30-H]

And the tank is a 100 liter tank, this is so cool.Z432-R has a same tank of this.

Hi Kats,

Great photos! Thanks for posting them.

SAFARI MOTORS need to do something about the engine in '4150'. It has some original components on it, but it is not the correct engine for that car. When I last saw it, it even had a 'Y70' head.......

About the works rally car fuel tanks: They were not identical to the Z432-R 100 litre tanks. Essentially the works rally tanks were modified versions of the 432-R tank, as they 'cut off' the two front corners ( to give clearance / protection from damage ) and relocated the gauge sender to the top ( whereas the 432-R sender was on the side of the tank, next to the filler neck - which was vulnerable for rally use ). So the 432-R tank is more of a complete four-sided oblong when seen in overhead view, whilst 70, 71 & most 72 works rally tanks had 6 sides when viewed from above.

Because of this modification, the works rally tanks actually held less than 100 litres of fuel. They had 100 litre fuel gauges that were often hand marked with a dab of white paint to indicate the max fuel level.........

Part way through 1972, works rally tanks changed to bladder and foam-filled types due to regulation updates. The cars that were built with ECGI injection had 110 litre bladder tanks, and some LY-equipped cars had 120 litre tanks with outside fillers housed in a cutout box with an 'Aston' filler cap built into the tailgate area ( so that the tank could be charged without opening the tailgate ).

It's never simple......

Alan T.

[26th-Z]

Thanks for the info, Alan.

[kats]

Thank you Carl,Chris,

I learn new today,This is very good and logical/technical description. I was not happy at over 6000 to 7500 RPM, but now I am happy.I did not do anything big except changing the tank, oh , but I did little adjustment of idle mixture when the restored Z432 tank was installed. Is this a reason,is not it?

Hello Alan!!!!

Thank you always, I have learned too.After I post that topic,I looked up the parts catalog for Fairlady model, I found something different between Rally tank and Z432-R tank.I was confused,but now it is clear , thank you Alan.

Alan,I really need to meet you,I have something to tell you.

Mr.Horiuchi said the sending unit for this rally tank is installed a new one still available from Nissan as same one for S30s.

kats

[kats]

Merry Christmas,

I for the first time up loading the video to You Tube.

I hope you can enjoy it in every country.

http://www.youtube.com/watch?v=1YzHa4yJzRg

http://www.youtube.com/watch?v=nbX1PkjYr_o&feature=related

kats

[g72s20]

Thank you Kats! and a merry Christmas to you too. The videos are great. I think the tyres highlighted with the yellow lettering really put the car in context. Perfect for a 1970 performance car in the hands of a serious enthusiast. It just looks (and sounds) so right!

[kats]

:)Thank you Jim

Please try another videos of S20 engine by someone,every engine has different sound,it is fun to see.

The blue Z432 in Related videos has OEM air cleaner and OEM Exhaust manifold,but custom made center and rear exhaust system and,it has got 2500cc.The sound is different.

kats

[Z CAR 77]

Thank you Kats for sharing the info, photos, and videos of your two fabulous Z-Cars. Have a Happy Holiday Season!

[kats]

Thank you Z CAR 77,

BTW,this car is a taboo,I think.But some one may want.A real 2000GT costs 25000000 JPY, this car 2500000 JPY, it is 1/10 price.

http://www.goo-net.com/usedcar/spread/goo/12/0100100102A4003376003.html

kats

[kats]

Hi,

I have been thinking up load these test reports from a gentleman who worked Nissan as a member of test drive section.

I think it is a good idea to show these before I turn to be unable do it.

Details will be available later I hope.

#1, PS30(Z432) performance report ( From 25th Feb 1970 to 14th Mar 1970)

#2, Avoidance of Exhaust gas entering in a cabin (11th Sep 1972)

#3, Improvement of stability at high speed cruising for HLS30Q for Europe

(from Feb 1970 to 27th Mar 1971)

kats