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Discussion Starter #1
My case is referring to the Weber 38/38 with the plastic float, where do you adjust your float height? One book says 35 the other says 40mm? This has a tremendous effect on jetting.

Redline will have me adjusting it below 40mm they say top of float 17.5mm 23mm to top of float (without gasket). Works out to about 42mm

Haynes 34.3mm 44.3 & Pierce suggest 35mm 51mm 馃槺

I removed the f-50鈥檚 & slipped in F-66 emulsion tubes, as I鈥檝e read the transition off idle is smoother.
I assume that the above recommendations are based on the f-50鈥檚
Bob said the emulsion tubes will have a large effect on the float setting on my FB post.
I鈥檓 just looking to get the float set for a starting point, then moving on to the jets.
 

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35mm to 51mm on this diagram.
For clarity, Lindsay posted a link for a Weber DGV, not a DGS. They have slightly different float settings

Float level for a 38DGAS is 34.3 mm closed, 44.3 mm open for the plastic float (40 mm and 50 mm for the brass float).

I run F-66 emulsion tubes on my 38DGAS
 

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Discussion Starter #4
For clarity, Lindsay posted a link for a Weber DGV, not a DGS. They have slightly different float settings

Float level for a 38DGAS is 34.3 mm closed, 44.3 mm open for the plastic float (40 mm and 50 mm for the brass float).

I run F-66 emulsion tubes on my 38DGAS
I may end up there. It runs pig rich @ 34.5mm with the 10mm drop on the 45 idle鈥檚 145 mains 170 ac鈥檚 afr 10.4:1, dropped in 140 mains 11-12:1 still way rich, it looks like 125 to135 mains if I run it at 34.3mm.
RallyBob says changing the emulsion tubes changes the float height, that makes total sense.
I believe those settings to be based on the f-50鈥檚. That said I鈥檓 getting the feeling that it鈥檚 a trial & error thing. I鈥檓 not ruling anything out.

Thanks for your input Kieth. How do you like the outcome on your 38/38? I realize you are running the f-66鈥檚 also.
 

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Discussion Starter #5
Here鈥檚 something interesting that I read this morning concerning the subject that might just help explain some of the controversy, why Redline gives out different advice, more in line with the advice given by some of the more knowledgeable guys on the 鈥Jeep Forum鈥.

I鈥檓 going to just do a copy & paste to save sifting through the threads below

Jeep forum:
鈥淥riginal "Weber" in Spain Promex then LCN has changed the float a few times from brass, to plastic to the smaller DFV plastic float. The smaller DFV plastic float is set at 17mm - 18mm in the vertical position from gasket to "TOP" of float. When this height has been set then measure the drop or the "needle travel" typically you would only need 2mm of movement regardles of the float movement off the pin or fulcrum鈥

So I鈥檓 thinking that there鈥檚 a possibility that the once reliable but printed litterateur being dated would explain the changes to the plastic float height. It seems that the brass float hasn鈥檛 changed over the years. The old DGAV carburetor I rescued from the junk yard made in Italy had a brass float and I鈥檝e never seen the larger plastic one. It might be very difficult to find a plastic float that was manufactured in Italy but perhaps someone out there can chime in if they do have one of these larger plastic floats.

More from the 鈥Weber performance.com鈥 site on the subject:
鈥滱s some may know, the original Italian Weber factory closed in 1992 (not too long after fuel injection took over). A few years later production resumed in Spain utilising all the same machinery and tooling. Today, a company by the name of LCN is the manufacturer of Weber carburettors & components. LCN is a major automotive supplier to some of the world's leading European car manufacturers. Weber carburettors in fact make up less than 10% of their business. Being involved so heavily in the Automotive industry, they must adhere to ISO 9001 manufacturing standards for all parts - including Weber carburettors. All genuine Weber carburettors manufactured by CNC are wet tested with an inert liquid before leaving the factory to ensure they perform as they are meant to鈥.

The guys on the Jeep forum use the F-7 to smooth out the off idle transition with the 17-18mm (top of float) height. From what I read they don鈥檛 rev as high in the RPM range as our short stroke CIH鈥檚 do so I don鈥檛 know if the F-7鈥檚 lean out up top or not.
 

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ISO 9001 is mostly a bureaucratic standard to show all paperwork is in order. Full employment for bureaucrats.
 

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Yup, created maunufacturing work instructuions / various procedures at several ISO 9001 factories in San Diego. Paid my mortgage.

Wonder what your Weber 38 mixture would be with a brass float?

'Plastic' is a misnomer, it's really just a closed-cell foam float, black in color.
Plastic Float Description:
Uphills, grades, bumpy roads affecting your performance? This will end any problem you may have with your Weber. This is the plastic float which is lighter than a brass so bouncing and fuel cutting on and off is no longer a problem. Fits 38/38 DGES and 32/36 DGEV models, not for 34/34. A great addition to your Weber carb.
 

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This is @... The Cub, My Plastid float got a giant Hole on the bottom, This was after I had a bad spark plug, a miss , and the float must of rattled on the bottom of the carb. Probably wasn't adjusted,, stock adjustment. The Engine would not Idle

Here are the Spec. for the Plastic Float and the Brass Float, and see how I did the the Basic Measurements, without any fancy tools..LOL. The measurement are in MM
I did end up using another Plastic Float,, 38/38 rule, but you have to jet them to your Engine,, every motor is different.. I have a 2.0 Opel Motor with cam,, and I using 135 Mains and 165 Air Correctors. 55 Idle
Idle to mains are the most important in Jetting a Big 38/38 Weber, to eliminate any dead spot, or hesitation from Idle to Mains ( It's over sized for it's application JMHO) Maybe this Post can help others too.





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Discussion Starter #9
This is @... The Cub, My Plastid float got a giant Hole on the bottom, This was after I had a bad spark plug, a miss , and the float must of rattled on the bottom of the carb. Probably wasn't adjusted,, stock adjustment. The Engine would not Idle

Here are the Spec. for the Plastic Float and the Brass Float, and see how I did the the Basic Measurements, without any fancy tools..LOL. The measurement are in MM
I did end up using another Plastic Float,, 38/38 rule, but you have to jet them to your Engine,, every motor is different.. I have a 2.0 Opel Motor with cam,, and I using 135 Mains and 165 Air Correctors. 55 Idle
Idle to mains are the most important in Jetting a Big 38/38 Weber, to eliminate any dead spot, or hesitation from Idle to Mains ( It's over sized for it's application JMHO) Maybe this Post can help others too.





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Great post Mike. The reason I started this thread, hopefully to get more input as to where people actually have the plastic float on their Weber鈥檚 set at, I am hoping to hear from people using the plastic float in the 32/36 as well. Funny how Redline & Pierce, the two main genuine Weber distributors do not agree on the plastic float height.

Thanks for adding what you have, in the detail that you did. I thought that I read on another post you had that you were using the f-66 e-tubes? You mentioned cam, would that be a near the 1.9 stock hydraulic grind?
It sounds like you鈥檙e happy with your set up, very close to what I鈥檓 running engine wise.

Wow! 55 idles are big for this carburetor. I did try the 135/165 main combo with the 45 idles and it ran too lean, well stated about it being a lot of carb for a small engine. I鈥檓 upside down from your set up right now with 45 idles 145/185 main/AC鈥檚, it runs fairly smooth but seems a bit too much on the mains.

I鈥檓 usually between the 45 & 50 idle jet range (.75 to 1.5 turns out on the mixture screws) & 135-145 mains, air correctors largely dependent on the float level. In fact all three are largely dependent on the float level, when it gets right down to it, in my experience.

Since I鈥檝e tried just about every height setting on the plastic float from 35-42mm, never sure what the ideal was. Recently I鈥檝e been using the brass float just 2-3 mm higher than the 41/51 setting. Using the f-66 e-tubes I鈥檓 under the understanding that the float height is to be set at a just a little bit higher setting with the brass float anyway.


Also very interesting post Lindsay, on the off roading need for the plastic, or 鈥渃losed cell foam鈥 float I never knew that, but it makes sense.
 

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I using a combination cam from OGTS
With the 38/38 Weber. On a fresh built 2.0 l Motor. 2 inch ss exhaust.
Bigger exhaust effects jetting and tuning
IMHO. the problem am having is with a combo cam.. on Opels you must set the total advance in the Distributor. Using a beefier Cam Which I have never done before.. need to be shown how to set total advance
So I can learn maybe somebody has a you tube on Opel GT GT Distributors total advance Method?
Also, while jetting and leaning carb.
I found sometimes to tweak the advance a bit to remove any slight hesitation
Hesitation in acceleration is from carb switching from idle jets to mains
And YEA F66 Emulatuon Tubes as per RallyBob
 

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Discussion Starter #11
I using a combination cam from OGTS
With the 38/38 Weber. On a fresh built 2.0 l Motor. 2 inch ss exhaust.
Bigger exhaust effects jetting and tuning
IMHO. the problem am having is with a combo cam.. on Opels you must set the total advance in the Distributor. Using a beefier Cam Which I have never done before.. need to be shown how to set total advance
So I can learn maybe somebody has a you tube on Opel GT GT Distributors total advance Method?
Also, while jetting and leaning carb.
I found sometimes to tweak the advance a bit to remove any slight hesitation
Hesitation in acceleration is from carb switching from idle jets to mains
And YEA F66 Emulatuon Tubes as per RallyBob
I鈥檒l make a short video next time I tune my 2.0 up, if someone doesn鈥檛 beat me to it. I鈥檓 running 36掳 total & 14.5掳 advance at 850 rpms, with the smaller cam I鈥檓 thinking of scaling it back down 4-6掳@ idle to 8-10掳. I鈥檓 also using 6-8掳 ported on the vacuum advance.

To set up the total you just need to be a tiny bit on the brave side, if you don鈥檛 mind moving the distributor near the loud racing fan. Plug off the ported or manifold for the advance if applicable.
I usually stick a shim (couple popsicle sticks) in between the throttle and throttle stop & let it run in neutral @ 4,000 rpms that way you know the timing is all in. Using the timing light with a dial line up the ball & pointer on the flywheel if known to be accurate, I checked mine with a dial indicator so mine is spot on. Then just lock the distributor and double check. I highly recommend setting up the total advance as opposed to just setting it up at idle speed, as all distributors have different amounts of total timing.
Actron makes a dependable inexpensive timing light with advance. You鈥檝e probably seen this thread starting on post # 50 on down is my contribution on how to modify one of the common Opel distributors if you鈥檙e so inclined. That might be more than you鈥檙e wanting to do though. I had to do that to bring my idle up to 850 rpms on my 32/36. The 38/38 has plenty of idle speed with less than 1/2 turn in on the speed screw.

I notice how much better the flow is with the Rallybob recommended 2鈥漻 2.5鈥 exhaust and the sprint after experiencing the 38/38, the difference wasn鈥檛 quite as noticeable on the 32/36.
It just goes to show you how futile jetting advice can be over the internet, not that it鈥檚 not fun. It鈥檇 be great if Vincent weighs in on his float level, brass or plastic he has had close to what you do with smaller exhaust valves, it鈥檚 interesting to see your 135 mains vs. the bigger ones. I tend to like running on the lean side. I鈥檒l post up when I get around to trying the 135鈥檚 again. My float settings were all over the place before.

So far on the plastic float that鈥檚 two I鈥檝e heard from on our site with the 38/38 f-66 combo have set it at 35mm, I鈥檓 not sure how important the drop is as long as you have at least 2mm of drop on the actual needle. Anywhere from 10 to 16 mm on the float of drop is in the books, I doubt if it ever sees half of that (if that) unless you鈥檙e needle & seat are undersized. At least that鈥檚 what I can gather.
 
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