Weber DCOE 45 setting

[tamo3]

Does anyone have Triple weber DCOE 45?

I got Weber DCOE 45 - 152

E/T F16

Main Jet 135

Air Jet 155

Idle Jet 70F9

Pump Jet 45

Needle 200

I saw a lot of folks use 40 DCOE. But seldum to see people using 45.

I found one Japanese web site mention about Weber 45 DCOE with 280z, 240z setting.

Weber Carburator Manual - Google Translate

I wonder how useful of this setting is.

I'm planning to order "power pump jet" (Garage Carry-Back) from Japan.

Normal Jet

Power Pump Jet

Garage Carry-Back - Google Translate

But I haven't decide what is the good base setting combination.

I would like to exchange setting info!

Thanks,

tamo3

Edited March 8, 2013 by tamo3

[Lazeum]

You've missed the choke size. Without this info, it will be hard to tell anything.

Are they 34mm or 36mm or something different?

I can say that delta between main & air jet seems small but not unusual. Idle jet seems huge. If the engine runs well at idle this way, it shows choke size is probably very large. If you're engine is stock, they are probably too large.

You're not telling us how your engine runs also. it could be a good info to comment your settings.

You can go also to Hybridz, FAQ. There's a nice thread with tons of info about DCOE on L6.

Edited March 8, 2013 by Lazeum

[240260280z]

Looks like something for Keith Frank to expand on

[tamo3]

Hi Lazeun,

Forgot mention.

Mine us 36mm.

Also, my header is MSA 6-1 header.

Thanks,

tamo3

[30 Ounce]

What have you done to your engine? 3.0? Cam? Porting? If its stock those are huge carbs...

[Lazeum]

Check the link for more info if you need something else.

Regarding your setup, I assume your engine is stock. Every change that could affect VE would affect carbs settings so it is important to know.

If your engine is stock, 36mm venturi are on the large side of the scope.

I'm on the other side: running fully built L28 engine with 32mm chokes on 40DCOE. I'm out-running the carbs after 5000rpm. I need to switch to at least 34mm to be good.

[LeonV]

I've got a set of 45DCOE-152 on the workbench and will be putting them on an L28 in the coming months (hopefully by mid-April).

I also have 36mm chokes and a pretty good collection of jets going (including Keith's hypojets and e-tubes). Come by my house with your Z sometime and we'll have ourselves a little Weber party.

EDIT: as Blue alluded to, explore Sidedraft Central (it's a Yahoo group). That place is a goldmine. Much of the info you read online and even in books will be incorrect, misleading, and/or incomplete. Keith has been the most knowledgeable and informative person that I have ever dealt with when it comes to these carbs.

Edited March 8, 2013 by LeonV

[240260280z]

With respect to the accelerator circuit and its components, what seems to be the best for an L24 and L28?

Leon I saw where you switched to 0 spill and 0.53 pump jets and stock springs and I plan to try similar on an L24 later this spring.

Do you think it is worth trying stronger pump spring and maybe even a 0.60 pump jets or simply drilling out small jets to get the wider spray pattern shown above?

[LeonV]

With respect to the accelerator circuit and its components, what seems to be the best for an L24 and L28?

Leon I saw where you switched to 0 spill and 0.53 pump jets and stock springs and I plan to try similar on an L24 later this spring.

Do you think it is worth trying stronger pump spring and maybe even a 0.60 pump jets or simply drilling out small jets to get the wider spray pattern shown above?

Good question, and it depends on where you're at right now. My goal was to have it to the point where I could stomp on it at 1500rpm in 1st and take off without bucking like a bronco.

I first tried stiffer springs but that didn't work since they overcame the throttle return springs and made the car idle at 3000rpm.

Then I soldered up the spill jets and the situation got better although the engine still wanted more fuel on quick bursts of the throttle. The use of .53mm pump jets got rid of the hesitation although the AFR still goes a bit lean before settling back down. I haven't done so but .55 or .60 pump jets would probably be as good as it gets. Then I still need to get smaller hypojets to further improve my gas mileage (I can have my cake and eat it too ).

Here's a good post by Mike Riehle on the message board, when we were discussing accel enrichment tuning:

The springs control the pressure in the accel. circuit when it is activated.

All else being equal, stiffer springs will require smaller jets and softer

springs will require larger jets. Consider this a coarse adjustment to get

your jets in a reasonable size range.

The accel. jet size determines the rate of enrichment.

The bleed back jet size determines the duration of enrichment. My Alfa is

likes about 1 sec. of enrichment.

Mike R

So Phil, what are your current accel problems? Sorry for the side-tracking but I figure this will help Takashi in getting his carbs right too.

DISCLAIMER: tune your accel pump LAST! Your idle and main circuits should be at a "good" state at this point.

Edited March 8, 2013 by LeonV

[240260280z]

Great stuff Leon...Thanks! I'll get some 65's too for experimentation.

I think that it may also affect slow transitions too since the spills will be 0 so any pedal movement will always squirt fuel.

[LeonV]

Great stuff Leon...Thanks! I'll get some 65's too for experimentation.

I think that it may also affect slow transitions too since the spills will be 0 so any pedal movement will always squirt fuel.

No problem, helps to rehash my memory on what I've done and need to do anyway.

I didn't find that there was a big difference in slow transitions after soldering the spills but then again I don't have data to prove it, just observations of O2 readings while driving. I thought it would have a bigger effect than it did, too.

Slow transitions also mean that the accel pump piston moves slowly, allowing some fuel to "blow-by" the piston and not get pushed out through the orifice and pump jet. Theoretically. How much I don't know, but it depends on the seal the piston makes with its bore.

[tamo3]

Thanks for the great information!

I will check out Yahoo group.

Lazeum,

Yes, My 280z is currently stock condition. I'm planning to stroke to 3.1. That's why I got 45 DCOE instead of 40 DCOE. I heard upto 2.8l, 40 DCOE is better than 45 DCOE. I don't know the detail yet.

Leon,

Thanks for the offer! Once my 280z become drivable, definitely want to have weber party! I think a couple of more folks might be interested in SF Bay Area.

I have free time at lunch and finally I have time to rev my engine.

Still haven't install weber. I need to work on brake at first... All the brake fluid leaked out last 10 years on my Z.