Weber carburetor upgrade

[Foxmoto]

I recently upgraded to a weber 32/36 on my 510 l16 and I finished it all up and it idles great and drives good but if I get on the gas it has a bit of hesitation and then smooths out. I did plug and get rid of the emission system because when I bought the car it didn't have a smog pump. Anyways not sure what it could be any help is appreciated. Thanks

[Jesse C.]

How many turns on the air fuel mixture needle? 

[datzenmike]

On 10/15/2024 at 10:04 PM, Foxmoto said:

I recently upgraded to a weber 32/36 on my 510 l16 and I finished it all up and it idles great and drives good but if I get on the gas it has a bit of hesitation and then smooths out. I did plug and get rid of the emission system because when I bought the car it didn't have a smog pump. Anyways not sure what it could be any help is appreciated. Thanks

 

It's a progressive secondary that starts coming in at about half throttle. Avoid flooring it at low speeds, try less than half throttle to start and step into it as the engine revs up. With a bit of practice you will get the feel of where that bog area is at low speeds and avoid it.

[Foxmoto]

Thank you for the advice. I've have gotten used to the throttle know and I have the air fuel screw set a 2 turns out.

[A-ko]

With tuning this dead spot can be eliminated. My '77 Toyota would have a dead spot in throttle when flooring it going from primary to secondaries. Richening the "secondary idle jet" (realistically it's more of a primary-to-secondary transition jet) by a few sizes completely eliminated it and now the throttle is smooth with no dead spots. Webers usually come from suppliers with a fairly generic tune that works well for most 4-cylinder engines, but are rarely set up perfectly for any specific application, even when they claim it's for a specific motor. I've seen countless people claim, even on Youtube videos that "this is just how Webers are" which is a hilarious assumption to make.

 

Every Weber DGV I've had whether it be from a vehicle a previous owner installed it on, or a junkyard, or a parts lot etc has had the same jetting, 140 mains, 160/170 air correctors, and usually either 50/50 or 50/60 idle jets. Usually "good enough" if you want to just get used to how the default jetting feels on your engine, but getting a jet kit, understand what jets control what, and a little tuning can go a long way. Generally 140 mains are OK (if a bit rich) for a good feeling engine for most sizes between 1.5L-2.0L, but the idle jets are usually either wrong or only vaguely in the ballpark. I had an '81 Civic with the 1.5L EM1 engine and it required a 45 primary idle jet, while my '75 Corolla with a 1.6L 2TC requires a 55 primary idle.

 

A lot of factors can determine what is right for your particular setup, I'd recommend getting one of the $60ish jet kits for your engine from Redline and messing around a bit.