240z Choke

[vramjee91]

Hey guys,

 

Just wanted some advice:

 

Do I need a choke? I am currently running an L26 with twin carbs. Is there any way to bypass the choke without going to EFI?

 

Cheers

 

Vivek

[andyk_79]

No choke on a cold Melbourne morning? You might get the engine started but it would be a PITA.  Others more knowledgable than me can comment on whether the rich mix also protects cold internals?

[1600dave]

Why do you not want a choke ?

[44014]

Jake (d3c0y) use to wake me up at 6am in our early 20's to put my hands over his trumpets so he could start his car on cold mornings, then sit there revving it to 2500rpm for 10 minutes outside my bedroom window so he could back it out of our driveway to get to work... I hated doing this!

Yes you need chokes on a twin carb l26.

The problem witht the hitachis is that they have no accelerator pumps so rely heaviily on the extra vacuum the choke butterflys provide to suck the raw fuel out of the bowls.

The richer mixture provides no extra engine protection and actually causes harm as it washes the bores with excess fuel and causes more wear. But fuel does not atomize very well when the metal it contacts is cold as it tends to form larger droplets on the port walls which is harder to ignite opposed to well atomised fuel when the engine warms up.

Hope this helps.

Cheers Doug.

[Zedman240®]

The only cure for not having a choke is EFI.

An engine block warming up absorbs all the heat made in the cylinder while its running so more fuel is needed to put in more heat for the burning process. You could always install a heating element in the block/sump to keep the engine hot all the time...

[chris240]

I dont have a choke on my tripple webbers, start easily, idle perfectly, including minus 2 degrees last sunday morning.

When I had the twin pommy SUs I found I needed choke for initial start up, then backed them off after 30 seconds or so..mind you, they where bought new and I had them properly installed and balanced.

 

[PeterAllen]

I once borrowed a car from a member of the Moran family and he told me "the choke was in the glovebox". I think that's what he said.

[vramjee91]

Cheers for the comments guys.

 

I just didn't like how the current Choke mounts onto the centre console, and was trying to figure out a way to not mount it there. It seems to put unnecessary pressure on the console.

 

Might need to think about where else I can relocate it.... Or I just go with Triples

[adam]

I'm running an L28 with 240z twin SUs without using the choke and besides having to warm the car up for a few minutes, there's no issues. Starting first thing in the morning may be more difficult but I'm not entirely sure having never used it before. Without warming the car up for a minute or so, the car hesitates.

[1600dave]

Stuff like 1600's, 180B's, etc have an under-dash choke knob rather than the console-mounted lever.

 

Maybe grab one and see if its long enough to work on a zed ? 180B SSS could be the go, this is a twin cable setup, one for each SU. If you want to try this, I could find one in the shed and measure it for you ?

 

Adam, everything you describe is what the choke is designed to eliminate (hard starting, hesitation when cold, not being able to use it till it warms up).

 

SU's have no accellerator pump, so stomping on the loud pedal a few times before starting (a la webbers) has no effect, all you are doing is opening and closing the butterflies.

[Scoota G]

Hook it to your handbrake. Choke on to start then warm up, handbrake off and go. Would suck if you need to do a roll start on a steep hill but. Dale has an efi setup that would be better suited to a stock engine.