45's are a lot of carb for a 2.4L engine, most people run 40's

10 minutes ago, Patcon said:

45's are a lot of carb for a 2.4L engine, most people run 40's

It is not a 2.4. It is an L28 with flat top pistons, a P90a head shaved 1.8mm, and a 72 degree cam.

If you use 45's then consider a 33 or 34mm choke.  The transition from the 33mm choke to the larger 45mm throat (vs 40mm throat) is the challenging tuning aspect to address according to Passini (fuel will precipitate).

Below is a table I made to help fit side-draft carbs to Datsun I6 Engines of different displacements and 6500rpm redline. 

• The red trace is for racing applications and is taken from the Weber's formula.
• The blue line is extrapolated for street.
• 3 real-world data points are plotted to validate the extrapolation.

For an L28 street application, a 40DCOE with 32 or 33 mm choke is the ideal.

For 50DCOE racing and running at a 6500 redline, one will need a 3.4litre displacement engine. 

note for racers: Operating at higher RPM's than 6500 pushes the red  line up.

 

Edited June 3, 20186 yr by 240260280

A good way to destroy drivability..Even on mine with a 262 cam I got nothing under 2k and the power just starts a 4k, above that it comes alive but not the friendliest for taking off from street lights in a civil way., in other words...its a hooligans car.

Jeff,

FYI:here is a long thread on optimizing 45DCOE's on an L28.  We are getting closer to a final optimized state but there is one unfavourable  parameter we have not been able to tune out yet .  Hopefully we will get it resolved before you go to triple 45's so that it can help in tuning your application.

https://www.classiczcars.com/forums/topic/56375-weber-selection-and-initial-jet-tuning/

 

This week I get a quick coat of Epoxy Primer on the shell.

 

  

Enjoy your time in LA, Jeff. Way worse places to be than Newport! Ortega Highway's probably your best drive down there.

@Home Built by Jeff

I don't think I ever saw you comment on your new primer gun. Do you like it? Is it worth it to invest in high quality guns?

Jeff, will you be making a vegas run?

1 hour ago, Patcon said:

@Home Built by Jeff

I don't think I ever saw you comment on your new primer gun. Do you like it? Is it worth it to invest in high quality guns?

Realistically, the finish for primer doesn't require a special gun. When it comes to colour and particularly clear, that is when a good gun is worth while. Just to get a nice clean consistent coverage.

25 minutes ago, tzagi1 said:

Jeff, will you be making a vegas run?

Unfortunately not this time. This will be a flying trip, I get in on Sunday arvo, work the whole week on the engine and then fly out Saturday arvo.

On 6/3/2018 at 5:45 AM, Home Built by Jeff said:

This is what I have for the Z

Triple 45mm OER’s 

Perfect choice.

On 6/9/2018 at 8:18 AM, Jason240z said:

Perfect choice.

The only better choice would be 47mm OER's. Enjoy your trip you and the Mrs.