510 Su's

[Captain Obvious]

6 hours ago, zKars said:

The flat tops in this case have no resemblance to the 73-74 Z carbs. Other than the air by pass hardware, they are just round tops with, well, flat tops....

I disagree with that 1000%. The only significant differences between what you have here and the 73-74 carbs is the integral float bowl and the inclusion of a REAL choke. Other than that, those 38mm flat tops are conceptually identical to the Z flat tops.

So for all the folks who poo-poo the Z flat tops, but are drooling all over these things..... I got one word. "Hypocrite!"    

[Patcon]

@NVZEE

Where are you sourcing all the excellent diagrams?

[NVZEE]

Diagrams are from the “Nissan Motorsports Schematic Catalog”, p.n. 99996-M8015. Carl Beck posted a pdf on his site:

http://www.jdmjunkies.ch/wordpress/2016-05-14/240z-nissan-motorsports-schematic-catalog-99996-m8015/

http://zhome.com/NissanMotorsportsSchematicCatalog.pdf

Edited December 4, 2017 by NVZEE

[Patcon]

I couldn't get to it...

and is that a pdf link, because I can't highlight it...

[NVZEE]

Updated links. The first one is a host page for viewing online and Carl's zhome url is a download.

[Patcon]

Much better, thanks

C

[zKars]

Got these beautiful FLAT TOP carbs running on the 510 tonight.  They run SO well.  Took it out for a quick back lane romp and had TOO much fun. 

Here is proof of concept.  Note. The idle is happening with the throttle blades 100% closed.

I swear I'm going to get fake plastic hemi-spherical caps made that you can snap on your flat top bells so you don't have to be embarrassed every time you open your hood...

And no laughing at the roof rack or the mack-tack paint job....

 

Edited December 14, 2017 by zKars

[Stanley]

Saw this today, not much information but something about modifying flat tops for racing.

https://www.zdriver.com/forums/240z-280zxt-s30-s130-tech-tips-275/carburetor-differences-20083/

[Patcon]

They sound good

[Captain Obvious]

12 hours ago, zKars said:

Note. The idle is happening with the throttle blades 100% closed.

I swear I'm going to get fake plastic hemi-spherical caps made that you can snap on your flat top bells so you don't have to be embarrassed every time you open your hood...

I know you know this already, but the idle is supposed to happen with the blades completely closed. That's one of the common ways that people who don't understand the flat tops screw them up.

As for being embarrassed when you open the hood, I've got a better idea. Do what I did. You've got a lathe, right?

ROUND TOPS!!!

[zKars]

Jolly good! Wouldn't have imagined there would be enough meat to do that. 

I'll see if that's an option on these miniature 38mm wonders.

[240260280]

CO is my hero!