This is like having an uncle who's an accomplished racer, mechanic and friend. Learning volumes from this series. Besides, your shop is fascinating and fun to look at.

I love your videos, so carefully shot and edited with simple clear explanations. It really feels like attending a university lecture. These have helped me immensely and I appreciate your efforts.

Straight to the point, put to practice, super easy to understand, best tutorial I’ve seen so far 👏🏻

Thank you for an excellent tutorial! You won’t believe how I’ve been looking for something like this😊.

‘Progression holes’...always wondered what they were for...learned something new again. Thank you sir.

uff finally. I have been waiting for this one for quite some time. Looking forward for part 2 :) thank you!

Spanish made Weber DCOEs 45 152 G etc have a finer thread on the idle screw, 2,5 turns works instead of 1,5 turns mentioned in this excellent video.

I have an 83 corolla with a carbed 4ag. All of your videos have helped me so much with this. Awesome to see you revisiting the subject!!!

Excellent video. Explanation that I understand having battled to get my DCOE 40s right on my Alfas. Thank you for your time and effort. Great help. Will watch them all.

Have been preparing to swap my Volvo engine over to double 45 DCOE's. Your series have helped me rebuild them and I think this series will be a massive help with adjusting them. Thanks a lot!

Many thanks for the video, i felt like i needed to take notes - i suddenly felt the urge to fiddle with my own webers on my alfa!

your videos are so darned good. You explain everything so well. You must have a huge fan club! Thank you!

Hi, thanks so much for your videos, which are so helpful to me (especially SU's and Webers's carbs). I'm really waiting for the part 2 ... to help finally set up mines !

This video is going to be absolute gold when I'll tune my 1973 Fiat 124 spider!!! Perfectly explained step by step! Thank you so much!

These discussions are 1st class. Thank you. I would like to see a SU vs DCOE comparison. You have done in depth on each and can offer deep insights on this IMO.

Your videos are first class, Steve. Even my wife likes watching them and she has zero interest in cars. I was a little surprised at your comment about the Spanish Webers . Can't be that bad as they have been making them in Spain for 30 years and they're still in business. Regarding the Idle Mixture Screws, if the Weber is a 151, these screws will be the finer thread and taper allowing for finer adjustments but requiring more turns. one and a quarter with the coarser screw would be about three with the finer later type. BTW, Steve, I have a very similar set up to your GT for track days and vintage racing but mine is a roadster. Greg.

Best carburetor for any application! Infinitely tunable but you must know how!!

Excellent video, thank you so much for the explanation on how to adjust the Weber side draft. I just installed a 45 dcoe on a datsun L20B and the progression is way to lean. Your videos gave me what I needed to correct the issue

Very good information regarding cam specifications, even with the difference in tuning my boosted engines requiring less duration and to my high comp NA the tuning is different on those factors you covered. Great video Steve 👌

Very useful, thanks for taking the time to make this film.

Fantastic explanation it's sounded so easy if we carefully listen and follow, tqvm sir ❤❤

Steve - FANTASTIC video - I was going to ask about the Spanish Weber screws since I realised they must be different while trying to adjust mine, but I see that question has already been answered here. Look forward to the next instalment!

I have been tuning the low speed circuit for over 20 years. Idle jets. Idle feed restrictions. Did it on a holley on a 429 ford . Went from 0.031 idle feed restrictions to 0.036" idle feed restrictions by test driving and drilling them 0.001" at a time. The car owner came back with a complaint. He can't pull away from any stop no matter how he feathers the throttle. He spins the rear tires. Did that to a straight six dodge dart. Now it will burn rubber too. When i use a air fuel ratio gauge with an oxygen sensor in the exhaust. I bring the rpms up to around 1700 rpms. Which in just below the speed the primary main jets start to trickle fuel. That lets me know if the idle jets are lean or rich. Thank you for the great video. Years ago i talked to a nascar carb manufacturer about billet metering blocks for holley carbs with vacuum operated plungers to shut off the idle circuit during engine braking on short tracks where flames come out the exhaust as the high manifold vacuum just pulls all kinds of fuel from the idle feed holes. He liked the idea. About 3 races from the end of the next season. Which was a short track. Close to the end of the race. The announcers said the car out in front does not seem to have flames from his exhaust during cornering. They pulled up the pit records. The guy in front was pitting every 56 laps. Where everybody else was running out of fuel at 51 or 52 laps. Fuel mileage during a race can win a race. Careful searching might find weber idle stop solenoids. With an adjustable vacuum switch hooked to manifold vacuum. One could set the switch to turn off the idle stop solenoids during high speed engine breaking to save fuel during a race. I also like using the weber and solex air bypass screws as that allows me to preset the throttle plate to expose exactly enough of the idle transition slots or ports. Getting the best fuel economy and instant throttle response.

Another great informative video Steve

Thanks for another great video, Has taught me plenty and with changing idle jets on mine, I have achieved a great setup..keep up the good work..

Was desperately waiting for your video about this topic! I just finished my 1979 VAZ 2103 build with DCOEs and as expected yet they run like shit 😂 Higly appreciated, I really value your way of teaching 👍🏻👍🏻🙏🏻

Excellent video. Clear, concise, very informative.

Thank you for such excellent detail of this subject. The best video on KZfaq regarding this. I have twin weber 45 DCOE that I bought for my BMW 1975 e10 (2002) over 30 years ago and could be calibrated or find someone to do it for me. Remove it from my car due to that and put aside the carburetors. A few months ago after restarting the car, reinstalled them back in the car and was hoping find some info on internet to be able to assist me to calibrator these twin carburetors. Watch so many videos but non explained the was you did. As I said earlier. Yours is The best video on KZfaq. Thank you very much. Have a great day. Regards JZ

Fantastic video sir you are improving our knowledge a very good teacher.👌

Keep up the good work, love the vids, you should be on tv.

Simple and easy wonderful lesson. Cheers Steve 👍 💯

Can’t wait to see the next part :) great tutorial - exactly what i needed - Thank you :)

Wow. Absolutely fantastic video and explanations. I very much appreciate your patient approach.

Another handy item for adjusting carburettors is the British made Iain Tyrrell, however, that is quite expensive and can't be stored in your toolbox.😁

Excellent explanation Sir. I like your no nonsense, calm way of explaining how things work. To me, a carb is a mysterious piece of equipment and most of the time, I used to ''adjust'' it by the feel of the pants or how it sounded. Sounds right? lets go! LOL Not exactly scientific and I most probably lost power. I learned a lot Thanks

Great information on weber tuning.👍

Great explanation about the relationship between the idle jet and the number of turns needed on the idle mixture screws. Also good you highlighted the importance of the position of the butterfly with respect to the progression holes - as per the Weber manual the edge of the butterfly should completely cover the first progression hole. The problem is that if you then adjust the idle speed using the idle speed screw this will move the edge of the butterfly - too much adjustment could lead to a less than optimum performance.

Thanks, good to refresh my recollection before the next sync and check.

Bom dia para todos!!! Gostei muito da aula de calibragem desse modelo de carburador duplo. Foi excelente às dicas que foi mostrada e a perfeição de como se deve ser feito o serviço com a mais perfeita calibragem. Adorei o vídeo 👏

Thanks a lot for this video, I'm tuning a pair of 45 DCOE Sherriberg (the chinese replicas) and now I know that I need one or two sizes up the current defaults 55F8's. Idle gets good at about 2,5 turns on the mixture screws, AFR gauge says about 13:1 at idle speed but once I push the throtle only a bit, it goes down to 20:1 and the engine hesitates and backfires. I have a set of 50F9's and another set of 60F9's. If none of these works I'll have to buy a new set lol, and again thanks, you strongly cleared my doubts!!

Excellent instruction, thank you

Nicely explained Steve , thank you . Do not worry about your 'English ' , I understand you clearly , no problem . My Dutch is completely lacking ... the same as nearly 100 percent of your watchers most likely ! Engines , whilst I know for fact understand cuss words , those words can be in any language you choose ! Kinell

Thank you really, Mr Steve. Your videos are superb and the knowledge you provide us is really appreciated ! Thanks again!

Brilliant video 👏👏 can you make part 2 please 😁

Idle and progression are the MOST important circuits!

Great tutorial. Thanks.

Love your work 👍

As always very good thanks

Excellent sir 👌

super video weer! dank!

Very clear information theory and practice

Super easy explained. Tnx

Your the best 👊🏽🇹🇹

great info

Thank you so much for putting these videos together. I recently bought a Low-cost 7 with twin Weber DCOE 40s and with your help I was able to get them tamed. Looking forward to the next video. 👍

Can you please group all the DCOE 40 videos into one playlist? Thanks again for putting these together. Super helpful!

Appreciate it!

Muy bien!!

More more more:)) I have a set of 40dcoe for my alfa spider. This is good info. Its been too long since I played with these carburetors. Any chance you can do a video on solex 42 ddhf ? Or something similar.

the only issue is we cannot give more than 1 thumb up 😢 for everytime i watch this. Though i run a Mikuni, the basic tenents are the same.

Love the videos - amazingly helpful and I have learned tons. Thank you. Quick question - just bought a used set of 45 DCOEs for my Datsun 510. Previously had 40s. I noticed the 45s do not have a secondary Venturi tube that can slide out (as per my 40s and in your videos) however they have a bolted in support for the main jet. The main venturis appear normal. Is this a factory option or a modification by the previous owner? I have pictures but not sure how to send them to you. Much thanks in advance. Jeff

Thank you Steve! I feed your videos extremely educational. Does the 3.75 to 1.5 turns rule apply to the older DCOEs that have the idle screws recessed within a cavity in the carburettor and an O-ring underneath the screw head? I have read that this is the older type of DCOE (non-emission type). Thank you once again.

Brilliant video, I’ve got a DCOE connected in a draw-through supercharged setup. How does the emission control screw work? Would really help me pass the MOT I think.

Hi i am pablo from argentina i have 2 weber 45 dcoe into my fiat 128, i have a problem when i stop my engine the fuel level of the carburator goes down if i leave one day to another day and i dont know from where the level goes down, aparently goes to the cilinder but i dont know in wich part of the carburetor leave the fue into the cylinder when the engine is stoped. Thanks in advance and very good explained.

Thanks for all the help! I was wondering if tuning the idle mixture to achieve max vacuum on the manifold after the throttle valves is a thing on dcoes. I see people do this on other carbs but not dcoe/dhla

Excellent videos. Thank you! What is the small hand held shop light you use? I've searched and don’t find anything like it. Thank you🥽

Great video thank you! So when looking down into the progression holes i sould only be able to see the butterfly in the closest hole to the engine? Correct?

Really nice video, I have twin 36 dcnf on my 1.1 Fiesta, all running standard jetting from the Ford factory parts. I'm no expert and took a minute to get her running nice, I will say though my idle screws are around 3 1/2 turns out on most and I think 1 is on 3 turns. Would you say I should experiment with larger idle jets or is it different depending on carb types, dcnf dcoe ect. Current idle jets are a 0.47, she does cough a bit when cold but 20 seconds of choke and ready to drive ( daily car ) Thanks very much and great videos as always :)

Do you have part 2 out on tunning the Weber?

I have 2 Italian 40DCOE 27's & 1 40DCOE 2. What are the main diff in the bodies between them? Not the jets etc. I have 3 on a TR6 cyl motor. Any ideas? Thanks. I love your vids. So clear. I have learned tons. Please keep them coming.

Hello my good friend, I'm revisiting this video again. Do you know if the same idle mixture screw principles apply for Weber 38/38 carburetors?

hi, thanks for your videos, on 14 minutes, you say after adjusting them go back to all the screws and turn them in a quarter turn each however in your live running adjustment later on you did not do that, can you confirm ? many thanks.

Thank you for such an informative video. My 4 cylinder on 40 mm dellortos bogs when the throttle is opened quickly but fine when opened smoothly. Does this mean it’s running too lean on the progression ? I will check the number of turns on the idle as per your guidance

Hello can you help me on a carb for an 12a mazda its smoking because i think it gets too much fuel 🤔

So you keep opening the idle mixture screw until the RPM stops increasing?

Hi Steve, are you running the SU pump? I was trying to autocross Sun. and kept running out of fuel. I have a facet gold top @3.5psi Mikunl phh44 im trying to find out if the SU pulls and pushes? The facet model supposedly has 2' dry lift and is in original mgb position.

How do the idle mixture screw turns translate to the spain DCOE’s with a finer thread? This is an Italian carb correct?

What was shared was max in: 1.5 turns and max out: 3/4 turns. This is for the older Italian DCOEs. What should the figures before for the Spanish 151s?

Hello Steve, Any ideia when part two will be up?

Hello sir! Could you please share if having your Weber on such a tilt angle affected your tune? How if you had to, did you compensate?

i have mine turned out to 3.5 turns, on a draw through turbo set up. how many sizes is that so i know which size idle jest to get. thank you!

Please can someone help - I’ve set up a Weber dcoe 40 on my 998 fast road. Kent 266p and Peter burgess fast road head. I’m using a 45 F9 for the idle and on slow progression it revs nicely however if I dump the throttle it bogs complete and nearly stalls….. Current set up below, do I need a richer jet, can someone suggest what I should try…. I have a spare 50 f2 but I guess that is too lean? Choke - 32mm Main jet - 140 Air corrector 175 Emulsion tube - F2 Idle jet 45 F9 Pump Jet - 45 Needle Valve 200 Thank you!!!!!

Why 55F9?

I know this is being very picky RPM stands for RevolutionS Per Minute, not per minutes

Very interresting i am going to set them.thanks good information

I have some questions for you before i start spending money on this project, do you have an email i can write to? i would love some advice with your expertise :)