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Discussion Starter · #1 ·
I just put a weber dgav 32/36 on my dad's mgb and it runs terrible! i read about it and it said to convert the weber from progressive to both barrels working at the same time. it seems simple any one ever tried it. i would like to do that on my opel.
 

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Discussion Starter · #3 ·
not yet, and i dont know what jets are currently in it. and also if i convert it to non progressive will i have the same size main jets in both barrels? and is nonprogressive a realistic option or will it get bad gas mileage and or flood the engine?
 

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The primary and secondary barrels are different sizes and will require different jets. BTW, you won't see any power difference between having the butterflies open together versus one and then the other. The only difference is going to be in throttle response and even then it's likely not worth the effort.

A friend of mine installed an off the shelf kit to a Holley 4 barrell to make the barrells open together and on the first test drive the kit jammed the linkage at full throttle. We took the kit off(I was passenger) and it never went back on. It just wasn't worth the risk. BTW, we had to turn the motor off. Locking the steering column on a curvy back road at 65 mph was pretty darned scarry.

-Travis
 

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Discussion Starter · #5 ·
i am confident that i can get both barrels to work smoothly but i dont understand why it wont give it more HP. but the throttle responce sucks right now and it wont go over 3000 rpm in 2nd gear and it also cuts out all the time.
 

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I tend to agree with Travis. Why would it have more HP just because they open together? If you kept your foot down, they would both be open anyway. Try rejetting first.

When I first got my GT w/32/36, I noticed that it had a major "punch" when the secondary barrel would open. It just didn't feel right running just on the primary, so I realized I was spending all my time with my foot down to keep the rear barrel open. It started out with 105 main primary, 115 main sec. I bought a jet kit from www.racetep.com/weber. I went to 150 primary and 180 sec. The car ran totally differently. It pulled better all the way up and the big difference when the back barrel opened was gone. I could tell by the exhaust fumes this was probably a little to rich, but the plugs didn't look too bad. I never experimented with getting them closer because I knew I would be going to a 38 on the new engine.

Do a search. I remember Rally Bob writing a good piece on jetting and getting the mixture screws set correctly.

Bestus,
James
Sorry so long winded!
 

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Start with the mains, which are pretty easy BTW.

1. bring the engine to operating temperature

2. make sure the choke is completely open, disconnect it if needed.

3. use the idle speed screw to bring the rpm to 3000 or so.

5. let it run for 5 minutes and turn the motor off.

6. check plug color on cyl #2 and adjust jets and test again

It's that easy. Note that if your running rich and put a good thick coat of carbon on the plugs it can take longer than 5 minutes to clean off.

The only other catch is that if you're detonating due to ignition timing your plug color will be useless. Fix/adjust the ignition first!

-Travis
 
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