Datsun-240z Vs Fairlady-z432

[xs10shl]

Many thanks, Alan.  I examined maybe 20 engine bay photos of Z432s, and pretty much every car owner had at one point changed the stock positions to something other than your photo.  Many had also swapped around the battery terminals, probably to ease access to the extra power runs for whichever replacement ignition system they were using.   My car is no exception.

RE electronic ignition: I had a vision this morning of perhaps re-using the existing wiring harness to eliminate a few of the custom wire runs needed by the replacement CDI, by manufacturing a matching connector that mates to the existing harness in some fashion.  I cant say for sure there's a way to get a 1:1 correlation of wires, but if I can eliminate some of the extra wires needed to make the system work, it would look a little cleaner under the dash. 

 

[xs10shl]

Well, I can't make it as clean as the sample model provided up-top, but it's at least better than it was.  There's a myriad of conflicting moving parts right where these wires drop down behind the engine, and I'm just now noticing the bracket which helps hold them away from the cowl was bent out of position by the previous owner, causing me to wonder how to solve the clearance issue.  Some more work to be done on that side, including moving the wires to the other side of the choke cable.

[kats]

10 hours ago, xs10shl said:

Well, I can't make it as clean as the sample model provided up-top, but it's at least better than it was.  There's a myriad of conflicting moving parts right where these wires drop down behind the engine, and I'm just now noticing the bracket which helps hold them away from the cowl was bent out of position by the previous owner, causing me to wonder how to solve the clearance issue.  Some more work to be done on that side, including moving the wires to the other side of the choke cable.

I really love this kind of conversation, thanks!! I want to write a bit something about the cramps, when I come back home.

I like to see the work of your Z432 , please post anything anytime here . I am learning new everyday and it is very interesting.

Kats

[kats]

23 hours ago, HS30-H said:

Stock PS30 battery cable routing should be very similar to stock S30 and S30-S battery cable routing for cars made during the same period.

The two cable run from the battery, along the firewall at the same level, over the top of the bonnet/hood catch bracket, and then turn down towards the bellhousing and starter motor - with their last holding point on the firewall being the dedicated stand-off clamp which is quite similar to the Mater Vac hose bracket. Small bolt-on clamps hold the cables to the firewall.

I think people started routing the cables through the catch bracket because it acted as an extra guide, and perhaps looked a little neater. Strictly speaking, it is not correct.

 

Thank you so much Alan, your inputs are perfect. 
I need to look how my Z432 has them . The small bolt-on cramp should be three for Z432  , four for all the other RHD S30 series . 

Kats

[xs10shl]

Apart from the standoff by the throttle linkage (which I've now wrestled sort-of into place), I have 2 clamps just under the cowl, with a possible location for a third by the positive battery terminal, under the inspection lid. But that's the only place where I can see where a third clamp could go. You can just see the bolt hole on one of Alan's photos.Is this correct?

My car's clamps were removed years ago, so I quickly fabbed up some temporary replacements, while I wait to get some from my mechanic.

 

[xs10shl]

Doing a little more sorting - car has not really been used since 2010, other than once around the block every now-and-then.  I've got an annoying issue with what I think is fuel delivery. A prior owner put Spanish Webers on (my least favorite variant), and the engine basically stops pulling at 3000RPM, so I suspect it's running slightly lean, and is also in need of different jetting.  Another potential culprit is the airbox - any experience (anecdotal or otherwise) on what removing the airbox does for higher-end response?  I ask, because this engine is carbureted and jetted identically to the KPCG10, right down to the emulsion tubes, but the KPGC10 doesn't suffer from the same lathargy.  Compression great on both engines, and same exhaust manifold. The only real difference is that the Z432 has a stock airbox fitted, and the KPGC10 does not.  I suppose I can just unbolt it and see what happens.

Edited February 22, 2022 by xs10shl

[kats]

2 hours ago, xs10shl said:

Doing a little more sorting - car has not really been used since 2010, other than once around the block every now-and-then.  I've got an annoying issue with what I think is fuel delivery. A prior owner put Spanish Webers on (my least favorite variant), and the engine basically stops pulling at 3000RPM, so I suspect it's running slightly lean, and is also in need of different jetting.  Another potential culprit is the airbox - any experience (anecdotal or otherwise) on what removing the airbox does for higher-end response?  I ask, because this engine is carbureted and jetted identically to the KPCG10, right down to the emulsion tubes, but the KPGC10 doesn't suffer from the same lathargy.  Compression great on both engines, and same exhaust manifold. The only real difference is that the Z432 has a stock airbox fitted, and the KPGC10 does not.  I suppose I can just unbolt it and see what happens.

Hi , I don’t know much about GT-R , you are so lucky that you can compare your Z432 with your GT-R !

Stop pulling at 3000 rpm , ummm, my Z432 was terrible once because the gas tank was

full of rust . Or I will check the ignition system , do they have the same igniters which is provided from Nissan original system ?

The original Mitsubishi igniter box might not be working properly if the car doesn’t pull right performance . I had it six of them in the past , two of them were not working properly even they were NOS when I bought them.

The air box has six trumpets in it , and it’s length is not so aggressive I think. But it is very good for street driving,Nissan engineers well considered of it . Your GT-R has different trumpets then it’s length matches 

for much sportier driving , then your GT-R go faster than your Z432. 
 

What I am feeling “ superior “ about the Z432 air box is, Z432 has the air filter box out of the engine bay , in front of the radiator. GT-R has it in the engine bay . Z432 ‘s S20 can inhale cold fresh air than that of GT-R , I believe it slightly provides additional output for the S20. But on the other hand , air flow is restricted and loses smoothness by the air box , so free air flow VS cold fresh air , please someone enlighten me !

Kats

Edited February 23, 2022 by kats

[xs10shl]

RE: rust.  Yes, this came up later today in a discussion with my mechanic.  There could be rust in the tank that has worked its way to the filters, and is restricting high-rpm fuel delivery.  I never bothered to check it out prior to filling the tank with gas last week. I'll have to do some fuel flow testing.

It's currently running an MSD ignition box which I needed to hastily install due to the last 3rd party CDI system failing just before it was due to be used in an article.  I had considered that it may not be working properly, but I can verify the timing appears to be normal, and advance curve works as expected - identically to the KPGC10, which is on a different CDI system.  The tach adapter is hopeless, and causes the tach to display too low - this is a fairly common issue with the technology, and I'll have to either tinker with it more, or more likely just discard it and install something else.   Comically, right now I have the MSD box Zip-tied to the existing CDI bracket, so whomever is sitting in the passenger seat may get a big red brick landing on their toes if it wiggles loose- ouch!

I'll do another run tomorrow and see if things improve.  I'd guess that if there is a clog, high-end throttle response might deteriorate as a draw down the full tank of gas.

[kats]

1 hour ago, xs10shl said:

RE: rust.  Yes, this came up later today in a discussion with my mechanic.  There could be rust in the tank that has worked its way to the filters, and is restricting high-rpm fuel delivery.  I never bothered to check it out prior to filling the tank with gas last week. I'll have to do some fuel flow testing.

It's currently running an MSD ignition box which I needed to hastily install due to the last 3rd party CDI system failing just before it was due to be used in an article.  I had considered that it may not be working properly, but I can verify the timing appears to be normal, and advance curve works as expected - identically to the KPGC10, which is on a different CDI system.  The tach adapter is hopeless, and causes the tach to display too low - this is a fairly common issue with the technology, and I'll have to either tinker with it more, or more likely just discard it and install something else.   Comically, right now I have the MSD box Zip-tied to the existing CDI bracket, so whomever is sitting in the passenger seat may get a big red brick landing on their toes if it wiggles loose- ouch!

I'll do another run tomorrow and see if things improve.  I'd guess that if there is a clog, high-end throttle response might deteriorate as a draw down the full tank of gas.

I hope you find the solution soon ! By the way , I have heard that NAGAI discontinued making their MDI tailored for S20 in2019 but there is another manufacturer produces CDI /MDI just bolt on to the S20 . I don’t have knowledge of aftermarket ignition system, so I have to stick with stock system .

Kats

Edited February 23, 2022 by kats

[kats]

On 2/18/2022 at 7:27 AM, xs10shl said:

Looking at Z432 battery cable routing.  Mine has clearly been monkeyed with, so I want to fix it.  Based on some stills I can see from your car, Kats, it's different from what a standard S30 RHD is, in that your negative is routed along the top of the cowl (where the positive would be on an S30), and the positive is right below it, and going through the hood release latch mounting.  Is this actually how they routed it? or perhaps I'm looking at older pictures of your car? (btw, that how the previous owner routed mine, but the number of zip ties used make me think that its probably not factory.)

 

 

 

I reviewed  my Z432 engine room, I found the battery cables we’re going through over the top of the bonnet catch basement during restoration, but I changed it at some point without any knowledge. 
And still now it is very fun digging into originality, I want to see a lot more examples to nail it down. 
The picture from the Service  Shuho shows the car doesn’t have the stand -off bracket , instead of that , there are two clips which is used also for L-series engined car. I can’t do the same thing because this car could be a very early one like production prototype cars . But I can see what is needed for S20 battery cable routings from this picture.

As you can see , S20 requires different throttle linkage which is obstructing battery cable routing for L20/L24 engined cars.

Kats

 

Edited February 23, 2022 by kats

[kats]

I have something to be clear, for Z432 , parts catalog says three bolt on brackets, four for other models. So , looking at my car and PS30-00055(Dec 1969) , both have three welded nuts which seems serving for the cables on the fire wall .
Then I thought I need to put #3 bracket just below the choke cable grommet (please see my post above). 
 

But , I am feeling something uneasy. Both cables should be clamped by the stand -off bracket, shouldn’t be? My idea for the negative cable routings doesn’t look right day by day .Nissan engineers intended to clamp both cables didn’t they ? 

And seeing the red PS30-00055 and other Z432 , the #3 nut looks never used . Even my Z432 would have never used it.

So , why parts catalog says three bolt on brackets ? 
Interesting!

Kats
 

Edited February 23, 2022 by kats

[HS30-H]

1 hour ago, kats said:

But , I am feeling something uneasy. Both cables should be clamped by the stand -off bracket, shouldn’t be? My idea for the negative cable routings doesn’t look right day by day .Nissan engineers intended to clamp both cables didn’t they ? 

And seeing the red PS30-00055 and other Z432 , the #3 nut looks never used . Even my Z432 would have never used it.

So , why parts catalog says three bolt on brackets ? 
Interesting!

I agree that the PZ-specific stand-off bracket was designed to hold both battery cables at that point (in order to route them away from the accel linkage, as you say). I see many stand-off brackets that are bent up and misshapen (probably because owners/mechanics were seeking access to the accel linkage) and the bracket needs to be in its original shape to route the cable properly. I have also seen variation in the cable earthing point (again, probably due to actions of owners/mechanics) so that will also change the routing...

About that mystery third clamping point: How about the captive nut on the firewall which is right over the battery? I feel like it is ideally positioned to hold ONE battery cable as it comes off the battery terminal - the one furthest to the outside of the car on the left - but seems rarely used. Possibly because of different batteries being retro-fitted?

 

Edited February 23, 2022 by HS30-H