Building A L28 (Na)

[Jeff G 78]

Looking good!

[TheCrazySwede]

Ok, so the motor is running and idling. 

Because I am not mechanically savvy, I'm sort of being tossed into the deep end right off the bat with these Triple Webers.

Zedyone_Kenobi has been kind enough to guide me through the process of making sure these guys are set up properly, so bare with me as I fumble my way through this!

I have the manuals (Haynes + the factory manual) and I've read up on tuning them on forums and such - but a lot of the guides assume you have a single clue about the subject at hand. I do not, so it's a bit tricky to grasp all the terms and the concepts of different variables and their respective consequences.

Wish there was a "Tuning Triple DCOE Webers for Dummies" 

[Zed Head]

Don't know if this will help or not - 

 

[TheCrazySwede]

Thanks Zed Head - Every little bit helps! It's all just a bit intimidating, but I really want to learn!

[madkaw]

So what's it doing or not doing? Some guys can't get them to idle, so your ahead of the game already. If you don't have a wide band O2 sensor on there yet, get one. It's not the only answer, but it helps with getting a tune. 

Search. There's more on this site about Webers than Mikunis, that's for sure.

[siteunseen]

I don't know if you've read this yet but it's pretty well written and informative.  Babalouie, about post #4

I've got a set but way too intimidating right now, I'm just getting comfortable with the simplistic SUs. 

 

 

[TheCrazySwede]

6 hours ago, siteunseen said:

I don't know if you've read this yet but it's pretty well written and informative.  Babalouie, about post #4

I've got a set but way too intimidating right now, I'm just getting comfortable with the simplistic SUs. 

 

 

That's super helpful - Thanks siteunseen!

That's just the sort of instruction I need!

[TheCrazySwede]

Got it to idle on its own and it's able to drive, but it's running lean. After inspecting the main jets, they seem to be way too small for what I'm dealing with (1.15mm) so that might be the reason why. Zedyone_Kenobi has been helping out a lot - I couldn't do all this without you all, so before I forget or get delusional from all the gasoline - Thank You all for your help!

Main Jets: 115

Emulsion Tube: F11

Air Correctors: Couldn't find the #

Idle Jets: Haven't checked

 

 

[Zedyone_kenobi]

Must know idle jet. Pull those jet covers and let us know buddy.

 

I am thrilled at your progress...Great work!

[TheCrazySwede]

On 2/9/2016 at 9:38 AM, Zedyone_kenobi said:

Must know idle jet. Pull those jet covers and let us know buddy.

 

I am thrilled at your progress...Great work!

A. What the Carbs came with / B. What I'm trying out

40DCOE Weber Carburetors

A. Choke: 28 / Mains: 115 / Air: 170 / Emulsion: F11 / Idle: 45F9

B. Choke: 34 / Mains: 145 / Air: 175 / Emulsion: F11 / Idle: 55F9

I also got new gaskets for the carbs, some air horns and those mesh lookin' air filters.

 

Edited February 16, 2016 by TheCrazySwede

[TheCrazySwede]

Got the car to idle well and runs pretty smooth, but still has a few hiccups. Runs a bit rough between the idle jet/main jet RPM hand-off. I've been suggested to check the float height, but have been busy with work. I'll check it when I can!

 

[Chickenman]

34 Chokes are pretty big on a 40 DCOE. On the street 32's should make it crisper and get rid of the idle to low speed stumble. If you can't get the drive-ability you want on the 34's, consider going down a bit in Choke size.

34's are OK on 45 DCOE's for the street ( On a STRONG engine )  , but reduce the booster signal too much on 40 DCOE IMHO. There is a ratio of throttle bore size to venturi size that has to be maintained. 34 Chokes on a 45 DCOE will create a stronger booster signal than 34's on a 40 DCOE because of the larger variance in size between throttle bore and venturi size on the 45's

This of course all depends on usage and engine specs. But on the street it's always best to be a bit conservative on choke size rather than a bit too big.

 

Edited February 19, 2016 by Chickenman
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