We're bringin' back the Flat Tops!

[motorman7]

44 minutes ago, Carl Beck said:

Great Job on that system!!  Would be interesting to see the replacement side by side with the original.   That Nissan Part Number shows up as "NLA" and part of a larger assy. How did your muffler man find it?  I have been hoping that someone would reproduce the resonators.....

 

Hi Carl,

     I will pull out one of my old exhaust systems and put them side by side in the next day or two.  My muffler guy has been around for a while and actually had a couple of these Nissan resonators back in his storage.  Unfortunately, I think he said this is his last one and I actually need another one made for my white Z.  I am not sure what Nissan model they were made for.  I think he told me but I forgot.  I will save the part number and probably keep a look out on eBay.

    I am surprised that Jay does not make these.  He makes the front and the back, but not the middle section.  My muffler guy does a pretty good job with these as the last one went in perfectly.

[motorman7]

Got the fuel tank sealed, cleaned up and painted.  Loosely installed the tank so I can start running all of the hoses.  That's always fun.

[motorman7]

On 5/13/2019 at 10:52 PM, Gav240z said:

I'm not sold on the bead blast finish of the intake manifold. I have been using vapour blasting to refinish my alloy parts and wouldn't try anything else personally. I'm not sure how good these looked 50 years ago, but I feel these look better than new and that may be "over" restoring for some, but I'm more than happy with it.

On 12/18/2018 at 7:38 AM, Captain Obvious said:

It's shiny... Too shiny.   (wink wink)  

I guess it's a bit of a challenge getting this just right.   Can't make it too shiny, don't want it too dull.  

 

I did get the manifolds installed last night.  Nice to be working back on the engine.  I temporarily placed the balance tube and flat tops on just to see what things will be looking like.  The balance tube is a bit of a challenge.  That brass plug on top is pretty hard to get out....even with the vice grips.  Will have to try the fire and ice method on this and see if that helps to loosen it.  Also broke off a fitting on the underside of the tube so I will need to drill and tap that out. 

I had to re-tap the threads for the air galley.  Those threads are M14 X 1.5 for anyone interested.

The good thing is that my water tube and exhaust tube for the EGR are in nice shape.  I did a quick fit check on those.  I will install as much of the tubing as I can before I actually install the carbs.

[motorman7]

Got a new passenger side window regulator.  Original had a broken wheel which doesn't work so well.  Installed that last night.  

Attached an exhaust system comparison.  My original is still at the muffler shop since I need another one, but here is the comparison with a spare I had in the backyard (That's a scary place)

Worked on the Carb plumbing.  I have one partially broken water system fitting that might still work.  Will check today to see if I can find a new one.  Also, I need the plumbing that goes from the water feed tube to the carbs.  That is totally MIA.  Will have to put out an APB to see if anyone has those.   Will post pics of parts I need  later today.

Was playing with camera settings on car pic.

[240Z73]

Looks like I don't have that piece, sorry.  

[Terrapin Z]

Well it is not as nice as your example, but it is available.

[motorman7]

 

47 minutes ago, Terrapin Z said:

Well it is not as nice as your example, but it is available.

PM sent

[jayhawk]

18 hours ago, Terrapin Z said:

Well it is not as nice as your example, but it is available.

 

Thanks Terrapin.  The community on classiczcars is a wonderful resource! 

 

[Terrapin Z]

I agree @jayhawk I have learned many things about these cars on this site, discovered some tricks, and have bought and sold here too. 

Great community indeed. 

 

Part is going out USPS today.Glad to help out.

[motorman7]

Being an engineer, I have to say that the carb heat shields inherently have a heat transfer issue.  There are black insulators between the heat shield and carb float bowl, but the securing bolts on the opposite side directly contact the heat shield and screw directly into the float bowl base.  This means that all of the heat that the heat shield is absorbing is transferred through the bolt assembly into the base of the float bowl., which means the shield is not helping very much and the float bowl is acting like a heat sink.  So, I added two gray fiber washers on the opposite side of the heat shield (from the insulators) so that the bolts do not directly contact the heat shield.  This way the heat shield is isolated and not channeling as much heat into the float bowl.  This is pretty much the only mod that i have made to the carbs and hopefully it reduces the susceptibility to vapor lock.

I picked up a new front flat top carb on eBay for fairly cheap...couldn't pass it up.  I am debating on whether to cannibalize it and put some of the parts on the rebuilt front carb, like the fuel filter, plastic cap and choke diaphragm.  Or, just install it on the front.  The problem with the second option is the finish is slightly different.  I am also considering trying to make the rear flat top finish match the new carb.  The new carb has a flat finish, so maybe a light bead blast would do the trick.  Still weighing  options here.

Got some new carb insulators...those look cool.

OK, now my latest issue.  The throttle linkage that connects the two carbs is too long.  I have three sets, and I think all are for SU's.  Never realized that the linkage for the flat tops is shorter than the linkage for the SU's.  You can see in that second to the last pic that the linkage is too long, my guess is that it is too long by 1/4".  Was thinking that maybe I assembled something wrong, but that is really not possible.  The carb throttle shafts control the span distance, and the linkage I have goes beyond the throttle shafts.  Anyway, will need to research this a little bit.  Maybe @Zup or @Captain Obvious can provide a bit of insight.

Ahhhh, the '73 linkage is definitely different.  Just added pic at bottom

 

Edited May 24, 2019 by motorman7

[Zup]

Hi Rich,

Yes, you are correct, the center linkage length is specific to the flat tops.

I have spares and will send it along if you need.

 

p.s. Small point of a different sort---Turn the vacuum servo diaphragm 180* so that the inlet from the throttle opener control valve assembly is to the rear as you face it.

Edited May 24, 2019 by Zup
ps

[motorman7]

3 minutes ago, Zup said:

Hi Rich,

Yes, you are correct, the center linkage length is specific to the flat tops.

I have spares and will send it along if you need.

Yes, please send.  I can cover you through PayPal....or trade you 2 of my SU linkages for your 1 flat top linkage ☺️