Ignition timing a whole lot of magic

This video is about setting the timing on a mechanical based distributor engine. I use a classic mini in this video to explain and demo how to do this work. Enjoy

[@neilallen8804]

From a retired public schools Industrial Arts (shop) teacher, you are an excellent teacher. I come from an automotive background, in that, my Father owned and operated an automotive repair shop for 30 plus years and yes, I ended up a 'motorhead' / hobbyist. I have a fully restored, 64 Volvo 1800S a couple of my Father's cars and others of my own. You sir "know your stuff" and relay your knowledge exceptionally well !

[@D3Sshooter]

Thank you so much Neil..

[@stolegrom6224]

Master is the one who knows to share the knowledge, not to keep it for himself. Appreciate your work, sir!

[@D3Sshooter]

I appreciate that!

[@keithmoule4154]

I had a Mini in the 1970's - seeing the details around the engine bay was like it was still in my garage! - the inspection cover over the flywheel, the clip in the bonnet (yep, from the UK here) for the bonnet stay and the rain attracting distributor.... What an immaculate car. Except for good ol' Mr Girling with that brake master cylinder. Congratulations on a fantastic vehicle. Oh, and I've just bought the Gunson Superstrobe on the back of this vid :). Here's another subscription.

[@tanyramos8045]

Never late to learn how ignition with points and condenser works, great video sir.

[@D3Sshooter]

You got that right! especially if you like to work on oldtimers... Thanks for the comments

[@PeterStern-t6l]

I can only join into the praising of your knoledge, teaching and video skills. Hats off to you, sir.

[@m.macdog5113]

I know absolutely nothing about engines. Your way of communicating concepts is excellent. I now have some understanding of the basics. It really helps when talking to my mechanic. I really enjoyed this video. Thanks mate

[@D3Sshooter]

Thank you very much!

[@matthewg9466]

Love your educational, instructional videos. I'm trying to get my old Spitfire with dual SU's tuned up and I am watching as many of your videos over and over before I attempt it. As many others have said, you're a great teacher: organized and know how to present.

[@dgriffin6074]

I just subscribed. This is the best teaching on ignition tuning I have ever seen. Thanks. BTW, you mentioned Relevant spark plug several times. I looked for them at my auto parts retailer; I saw Champion, NGK, Bosch but no Relevant. OK, just kidding. Great video.

[@thegeneral8019]

One of the very best tutorials I’ve ever seen. Everything’s very well explained and easy to follow.

[@D3Sshooter]

Glad it was helpful!

[@peterwhiting6264]

I’ve know the what and how since I was about 13 years old but now I understand a lot more about the why, especially the importance of points gap. Thanks for an excellent tutorial

[@D3Sshooter]

Thanks for the comments

[@peterwhiting6264]

@@D3Sshooter you are welcome. I always thought the points gap was about making sure the gap couldn’t be bridged by a spark. I never realised it determined the dwell angle and the power achieved in the HT circuit.

[@deangaryjames]

I used to do Crypton tuning years ago, i'm 63 yrs old and still tuning my minis, this video was a refresher course for me, thank you Steve

[@D3Sshooter]

Thanks for the comments Dean, we are about the same age, young at mind and hart... Will need to check the Crypton tuning

[@johnduncan8776]

That was the best explanation of static and dynamic advance I have ever heard. Thank You.

[@LoneStarMini]

This was absolutely brilliant. I cannot tell you how much sharing your knowledge is appreciated. Because I'm learning everything on my classic mini, I will watch this video multiple times to figure out all that you have shared... thank you

[@D3Sshooter]

Glad it was helpful!

[@jockofthebushveld299]

Excellent Theoretical & Practical explanations well done very professional,I have to say that is one of the cleanest Engine Compartments I've ever seen.

[@Giuliettashop]

Excellent Video!!! I am in the process of getting 7 of my late 50's and early 60's Alfa Romeos on the road and this information is absolutely Golden!!!! Thanks

[@traylorjbc]

One of the best videos I have seen on KZbin that covers this subject

[@TheR100RT]

Very informative video, great series with all the other ones on your channel. Really good analogy with timing and pushing the swing, will have to use that one from now on. Many thanks for your efforts

[@richardarnold3812]

I can never see me doing this on my car, but now i understand how it all works. A really comprehensive presentation :)

[@D3Sshooter]

Great to hear! and thanks for the comments

[@paulmuff9883]

What fantastic video I would say the best, most understandable explanation on this subject, many thanks 😊

[@paulmuff9883]

I would like to add that you are not only a fantastic teacher but your not mean like the guy on KZbin that tunes mini’s and SU carbs but is greedy because he doesn’t show the information on altering the needle to get the correct mixture for the engine because he wants to charge you for the privilege,😢🤬 You sir on the other hand are a true gentleman and professional, I watch your video on needles and mixtures and learn from it how to do it 😀 I had many apprentices under my teaching as a engineer and always give them my knowledge without holding back any information knowing that it was the right thing to do, so thank you for sharing your knowledge with us all 👍👍👍❤️

[@dongardner7137]

As always, Steve, your instructional expertise makes the complicated simple. I’m glad you mentioned “Old Rusty.” My postpartum blues will soon vanish.

[@D3Sshooter]

Right on! Thank you for the comments

[@ShaunCymruDS8]

Always a pleasure to see your enthusiasm and share your knowledge Steve and I appreciate the effort that goes into the process of recording/editing to share with the community.Keep up the good work!

[@D3Sshooter]

I appreciate that!

[@novakenss]

I wish I could have seen this video when I was a teenager in Auto Shop in high school. Thanks again for another fine instructional video. Ken

[@D3Sshooter]

Thanks for watching!

[@Imforeverenglish]

Wow! If only Haynes explained things that clearly. I thought I knew most of this stuff but your explanations are clear and concise...great work thank you for posting these videos

[@D3Sshooter]

Glad it was helpful!

[@barbfink6112]

Steve you’re fantastic. Have a Classic Mini and need all the help I can get. I have learned so much & can watch over again to make sure I understand! Bravo!

[@D3Sshooter]

Thanks for the comments

[@Eurostang]

This is the best explanation I’ve seen on KZbin and perhaps any other media! Love the videos keep em up 😊

[@sheep1ewe]

I must say that we are realy not spoiled with content of this high quality on KZbin, especialy not hidden behind a paywall either, Both the content wich is realy professional and actualy useful as well as the videos them self genuinly hold up the highest quality on Your channel!

[@D3Sshooter]

Glad you enjoy it! and thank you

[@novakenss]

After years of connecting the vacuum advance to the ported vacuum, I finally learned that the best connection is to manifold vacuum. This allows the engine to run cooler and better on the street and during lower RPM conditions. When throttle is opened, it decreases and the mechanical advance takes over. Port vacuum was used when the smog control era started in the late 60's in the US. In the old days, manifold vacuum was used. I've made this change to several cars and they always run better. You probably know all this already. Thanks again for your excellent videos, especially on Weber carburetors. I have 3 DCOE 40's on my '72 Datsun 240Z and they need proper set up and care. I've learned a lot from you.

[@D3Sshooter]

Thank you for the comments, much appreciated

[@johnmcauley3317]

Fantastic video Steve. Your camera work and explanation (s) are second to none!

[@D3Sshooter]

Glad you liked it!

[@marktelford2160]

Another very well done and informative video. Most people much under 50 years old will not have had much exposure to points ignitions. I probably would have shown the other end of the secondary coil connected to the negative terminal of the coil as electrically, it is and may help people with fault finding a dead coil. Also, as a couple of people have mentioned, you didn't include the condenser in your diagram or explanation. It can be a simple cause of a dead ignition system or the reason your points burn out quickly. While this type of ignition system is now considered 'old school', low tech and high maintenance compared to modern ignition systems, if you understand them, they are very reliable and easy to fix by the side of the road. Again, a very excellent tutorial as usual.

[@D3Sshooter]

thanks for the comments Mark, and a good point... I should have done that...

[@melvynwoodman5787]

True enough in theory, but now the spares for these systems are not required or produced in quantity anymore, they are often produced in dubious places to equally dubious standards such that replacing items with new doesn’t necessarily solve a problem or only does so for a short time leading to much frustration.

[@MookieZerang]

I've never seen such clear explanation as you do Mr 3DSshooter, thank you.

[@D3Sshooter]

Glad to hear it!

[@robertbaron8496]

He is an excellent teacher, takes the mystery out of many things.

[@GPZ_Biker]

This was a great video. Very very informative and delivered in a perfect way. Thank you. More videos like this on the technical ways to tune minis please. Youve gained a subscriber.

[@onboro_alfa_SGL]

Very nice, clear and comprehensive lecture for the fundamental mechanisms of the ignition system. Easy to understand. Thanks for the great video 👍

[@craigmalm1558]

Thanks much. Haven’t adjusted timing, dwell, etc since I ran a muscle car in the 60’s/70’s and now bought a 75 Porsche 914 that has not been run for 10 years and this was very helpful!

[@D3Sshooter]

Glad it helped , and 914 wow that is a nice car.... post a video, so we can see it....

[@Conor.Twomey]

Super video. Best explanation I have seen on advance in ignition systems.

[@D3Sshooter]

Glad you liked it

[@davewilliams9656]

At last! I no understanding what a DWELL ANGLE is. Such a good clear explanation. Thank you. I can apply the knowledge to my classic MG Midget!

[@Eaglekeeper1958]

This was the best video on the parts of the ignition system and how the ignition system work. And also how to adjust it to the absolute best setting so you can get the best performance from your engine. Thank you very much for taking the time to explain this in such detail. I really enjoy it. I have an MGB that was in pieces when I purchased it and I can already see this is going to be very helpful!😀

[@alspurs70]

Your videos are amazing. So clear and easy to follow. I’ve wtched all your classic mini ones in the last 24 hours. Please keep them coming.

[@D3Sshooter]

Glad you like them!

[@lavo6277]

Great video. I've often heard of advance curves but never really understood it.........until now. Cheers.

[@D3Sshooter]

Glad you liked it!

[@dv8r892]

Thanks for the excellent insight - explained so clearly and effectively. It would be a privilege to have you as a father/grandfather - so much 'good old' knowledge to be passed down :) Your videos on carburetors are of very high value to me - my classic corolla is going to purr thanks to your instruction - Cheers from Perth, W.A.

[@Scuba72Chris]

Thank you for the excellent explanation, the best I've seen so far. Your video answered so many questions that I had and it's given me confidence to sort out the timing on my Morris Minor. Keep up the great work!

[@aureliobrighton1871]

Wish I will have 'anything' together as masterful and calm eventually ... to watch and listen here is inspiring .. from and to any angle . Thankyou 'in advance' :)

[@LauriLevola]

Wow. A long video, but everything of usual interest has been but into a clear, consistent and (still) concise package. Liked!

[@D3Sshooter]

Much appreciated!

[@ronaldlwando872]

Commenting from Zambia, you have really helped me am doing Automotive Engineering

[@bmerfunitec]

What a beautifully expressed understanding of the ignition process. Thank you. I know a thing or two but...you added to my clarity of understanding and used the correct terminology in a way that I could grasp and improve my knowledge. You have bridged the gaps.Very grateful to you. Best regards. Merf

[@D3Sshooter]

Glad it was helpful!

[@iamrichrocker]

amazing prep and editing on this great tutorial...thank you for your efforts

[@D3Sshooter]

My pleasure!

[@mohabatkhanmalak1161]

Now that is 'fine tuning'. Very well explained, some of us need refresher tutorials especially when we are surrounded by electronic ignition vehicles. Fine tuning results in very good engine performance, the acceleration, power and economy are great. Glad to know 'old trusty' parts are on the way and looking forward to seeing her start.

[@D3Sshooter]

Thanks for the comments, indeed sometimes we forget all the old principles, although they still stand with electronics

[@mohabatkhanmalak1161]

@@D3Sshooter One of the ways I fine tune is to clean all ignition primary and secondary circuit connections and renew worn wires. I unscrew and sand down the connectors with emery paper until they shine, from the ignition switch (if its easy to get to) to the coil and distributor. The result is the coil gains more voltage and even this small gain is added to the total which in the secondary gives a much better spark. The engine will then have quick starting, better fuel economy and power. Usually commercial mechanics don't have the time to do this.

[@D3Sshooter]

@@mohabatkhanmalak1161 , that is indeed very good practice...and always a requirement to any further adjustments etc.

[@frankbartolo5223]

Hi Steve I knew all that but now I really know all that Great detailed description keep up the excellent work you are doing 👍🇦🇺

[@D3Sshooter]

Thanks 👍

[@rickperrotta]

What a great explanation! Thanks for sharing your knowledge in a logical and simplified way.

[@D3Sshooter]

Glad it was helpful!

[@Cavalier_Steve]

Thanks for the lesson I always wondered what the dwell measurement was, I thought it would be complicated but it was really simple the rest of it was beautifully presented. A big thank you. Steve.

[@D3Sshooter]

You're very welcome!

[@onepairofhands]

great video - you sir are a natural teacher !

[@D3Sshooter]

Thanks for the comments

[@lisaharris3868]

All these videos on the carbs, set up and timing are fabulous and exceptionally well presented. I only have one observation, when testing the advance curve of the ignition the vacuum advance should be left DISCONNECTED, it acts independently of dynamic advance. Vacuum advance is there to increase the advance when the compression ratio in the cylinder drops ( due to the vacuum in the inlet manifold ). Under low load, partial throttle, so partially open carb butterfly valve the compression ratio in the cylinder will drop below 10:1 and pressure in the cylinder will be lower, so the fuel air molecules are not so close together and therefore the flame front travels slower. The vacuum advance takes this into account and will increase the advance beyond that of dynamic advance. This ensures a cleaner burn and a better pick up from part throttle. In racing vacuum advance is almost unnecessary, as the throttle is fully open most of the timer closed.

[@dvrom]

Absolutely awesome tutorial, I started getting into vintage cars and has helped heaps, thanks

[@michaelgough9256]

Great video mate. Greeting from Australia. Very informative

[@D3Sshooter]

Sorry for the late reply , as i was away for work. But thanks for the comments.

[@nolanpadhwootan7225]

Very well explained 👌 one of my favorite youtuber

[@ianmorral870]

Great work, another fantastic and detailed tutorial, I have to be a little pedantic and say that, if an engine is set up and running properly, the fuel/air mixture doesn't explode it burns albeit aggressively. If it does explode then the engine is pinking, I remember this from my college days, it was one of my tutors pet hates if anyone said the fuel/air mix' was exploding.

[@D3Sshooter]

Thanks for the comments

[@grahamcollett688]

Excellent video. One of the best explanations I’ve seen on KZbin. Great work!

[@D3Sshooter]

Glad it was helpful! Thanks for the comments

[@mps737]

Fantastic video sir. You are an excellent teacher. Thank you.

[@therealringalls]

Thanks again for this! I'll be setting up my HIF44 this weekend on my 1275 mini. I may have some questions. I've watched all your mini videos a number of times.

[@D3Sshooter]

TXS for the comments

[@Budso01]

Thanks for a great video presented in a very easy-to-understand manner. I must, however, take exception to a couple of items that might be misconstrued by your viewers. 1) In the normal combustion process, the air/fuel charge burns rather than explodes. At the moment of ignition, the charge begins to burn, forming a flame front that burns outwardly from the point of ignition across the combustion chamber at a certain burn rate. This burn rate is affected by combustion chamber design, piston dome shape, and AFR along with cylinder charge filling, ambient environment, etc. If during the burn cycle, combustion temperature and/or combustion pressure exceed the fuel's ability to suppress detonation, the otherwise controlled flame front suddenly explodes, creating the "pinging" heard during detonation. As you mentioned, too much spark advance may create unnaturally high combustion temperatures and pressures that result in detonation. 2) Disregarding vacuum advance systems used for emission controls on older cars, the vacuum advance system was developed as a means to improve fuel economy at steady-state cruising speeds. For example, at 60-65mph, the typical car engine is loafing. Combustion temperatures and pressures are quite low, while AFR values are usually lean. The throttle plate (butterfly) is only partially open, creating high engine vacuum, an indication of low engine loading. Under these partial load conditions, the aforementioned flame front becomes quite lazy with its burn rate. If the best efficiency is to be obtained, the ignition timing needs to be advanced several degrees to compensate for the slow-burning charge. The vacuum advance mounted on the distributor of most older, vintage cars accomplishes this chore quite handily. The unit consists of an enclosed diaphram with two connections; a manifold vacuum (or ported vacuum) hose attached to one end, with the other end connected to the ignition advance plate by a metal rod. As engine vacuum rises in response to partial throttle, the strong vacuum signal pulls the rod via the diaphragm, advancing the ignition timing to adjust for slow fuel burn. Combined with both initial (static) and centrifugal advance, the total advance at this point may well be considerably beyond 40-45 degrees. When more power is needed, the throttle is opened and engine vacuum is correspondingly reduced. The drop in vacuum immediately removes all vacuum advance from the igntion points advance plate and returns the ignition timing to static and centrifugal alone. side note: It is important to remove the vacuum hose from the diaphragm and place a plug in the hose before setting the timing. This is particularly important if the other end is connected to the intake manifold. With no engine load and high Intake vacuum, the vacuum advance will be engaged regardless of RPM and adversely affect the outcome of the timing procedure. Once again, all of your videos are top-notch and very much appreciated. After selling my MGB thirty years ago, thanks to you I now know how the carbs work! Well done.

[@D3Sshooter]

Much appreciated, great write up !

[@kallehjelmstrom4010]

really well explained video. Let me guess, you must have been a teacher before. You make me think back to my high school days. In fact, I do not think today's high school students get this information.

[@D3Sshooter]

thanks for the comments, No teacher , but I did develop some new things ( electronics ) in the past and new methods that I had to sell to the management and lead engieers... so over time I have learned what I believe is the best approach to bring something across

[@jamewakk]

You are an excellent teacher, love your videos.

[@D3Sshooter]

Glad you like them! thanks for the comments

[@TornadoCAN99]

Great tutorial. Couple of new things I learned: That I can check & confirm my Mini's timing marks on the timing cover by looking at the clutch flywheel inspection port; That dynamic advance needs to be checked with the vacuum line attached to distributor; That I should never wear a hoodie sweater with laces dangling near moving engine part (this is the second video I've seen for timing a Mini where presenter was wearing dangling hoodie laces near the alternator & fan belt !! ;-).

[@D3Sshooter]

Thanks for the comments, the vacuum is not really needed for the dynamic acceleration test... but I did fit , because else I will forget it. Its the bob weights that do all the work for the advance..and yes the hoodie...

[@deangaryjames]

@@D3Sshooter i used to have long hair in the 70's, and whilst checking timing on a v4 ford the alternator pulled some hair out, lesson learned for me 😊

[@sjp52047]

That pretty much says it all. Great explanation. Regards, Solomon

[@D3Sshooter]

Thanks for the comments

[@christhjian9923]

I remember looking video like that few years ago and found nothing. That was amazing timing adjusting video really.

[@D3Sshooter]

Glad you enjoyed it!

[@georgehamp9871]

Outstanding presentation. Well done.

[@D3Sshooter]

Thanks for the comments

[@robertbandusky9565]

As always, excellent presentation 😎

[@D3Sshooter]

Thank you! Cheers!

[@WouterB76]

Actually ignition happens a few degrees before TDC, increasing with engine speed. Great explanation again!

[@D3Sshooter]

Thanks for the info!

[@JWONG-pu8ky]

Very underrated channel

[@D3Sshooter]

Glad you think so! Thanks for the comments

[@JWONG-pu8ky]

I got to your channel by watching the videos about the webber carburators and it is what ive been looking for a long time in understanding those carbs which i didnt find anywhere else, keep up this very good and informative contents 👍👌

[@vdel9036]

I've learnt a lot. Thank you for this lesson.

[@D3Sshooter]

You are welcome!

[@StephenJohnson-jb7xe]

I find the biggest problem of getting old and needing glasses is, when working on a car, if I need to turn my head to an angle to see something my glasses move and everything goes blurry. Even thought I have done this job, setting points and timing many times I still learned something today. I always thought the points sent a charge through the primary circuit when they closed which induced a charge in the secondary coil which then went to the dizzy. What you described is the exact opposite being that when the circuit to the primary is broken the charge is induced in the secondary.

[@D3Sshooter]

Thanks for the comments Stephen, tell me about it. yes, its the change in current flow that induces induction. have a look on your car and see what happens, the spark happens when the points open.

[@StephenJohnson-jb7xe]

@@D3Sshooter Hmmm everything I have is electronic ignition now. Which in a way is worse because it can be so hard to figure out what is wrong sometimes.

[@erikrezlman7900]

Thanks much for the videos and the details you communicate!

[@williamingleton7980]

very helpful and interesting. Thank you, it has increased my understanding a lot.

[@kerrygleeson4409]

Thank for sharing your knowledge Steve always interesting

[@D3Sshooter]

Glad you enjoyed it

[@philmahoney6656]

Really found this interesting , great video. Cheers

[@D3Sshooter]

Thank you

[@RoopGill]

Thank you so much. I learned so much. please keep it up.

[@D3Sshooter]

Thanks for the comments

[@demetrispatrikarakos5565]

Excellent presentation. Thank you for the tutorial. I have an Innocenti 1001 export and your presentations are really helpful.

[@D3Sshooter]

Glad it was helpful! Innocenti 1001 nice

[@DRW58]

Hi thank you for a very interesting video, I know more now than I did before I just have to put this into practice now to see if I can get my engine to fire up after a complete rebuild. I think if I can get the static timing set then there’s a chance it should run as I have a spark at all the plugs and fuel to a professionally refurbished carb.👍👍 Take Care Stay Safe Everyone Regards Dave 🏴󠁧󠁢󠁳󠁣󠁴󠁿

[@D3Sshooter]

Glad it was helpful! and yes with all the basic settings it wil start

[@RavinderSingh-xl3kj]

Morning mate good video, I'm just wondering if you have ever used Iridium spark plugs? I have a 1984 Mini Mayfair automatic, Would it make any difference ?

[@D3Sshooter]

Hi, yes I did use them and the spark quality is a bit better and they seem to last longer. But no major engine performance improvenments

[@RavinderSingh-xl3kj]

@@D3Sshooter Thanks for your advice have a good weekend

[@beniamino939]

I appreciate point-style ignition too.

[@D3Sshooter]

Thanks for the comments, I like it because its so simple. However I will move soon to a full programmable version with IPAD bluetoot integration... that is to come soon

[@andymiddleditch3855]

Very well made video, very informative and very useful.

[@D3Sshooter]

Glad you enjoyed it!

[@joelthomas818]

Really appreciate your vidéos. Keep going the good work.

[@D3Sshooter]

Glad you like them!

[@joelthomas818]

I really like what you do and how you teach it. This is directly applied on my car :)

[@fabrytomas]

Great video! Thank you, I really appreciate what you are doing!

[@D3Sshooter]

My pleasure!

[@erikdekoster4137]

Thank you for your post, very informative and helpful.

[@D3Sshooter]

Glad it was helpful!

[@AdamAnthonyAdventures]

Your videos are amazing - you’re a professor or ignition systems

[@lasorelay]

this takes me so much knowledge.

[@pascalnorvins2187]

Best video hands down sir 👌

[@joyeriaestesun2171]

wonderfully explained, thank you

[@D3Sshooter]

You are welcome!

[@T3glider]

Amazing explanation. Thanks.

[@hosrow]

Love your videos.

[@D3Sshooter]

Thank you!

[@doglegjake6788]

Excellent video

[@D3Sshooter]

TXS for the comments

[@roygardiner2229]

Thank you. There were a few points I did not fully understand so I shall have to watch the video again. In particular, when you were doing the dynamic advance you did it by adjusting a knob on the strobe instrument. But.....what does a rotation of the knob actually DO to make a change in the ignition system? Is it actually changing a position of the diaphragm in the inlet manifold, that you referred to earlier?

[@JamesParus]

Vacuum advance is for small throttle openings where engine doesn't ping easily. Cruising and deceleration. Idea is that when you give it throttle it would ping but then the vacuum goes down with high throttle and it drops to normal advance.

[@D3Sshooter]

Thanks for the comments, good point... and yes it can be slightly be seen on the dials

[@AJB1]

Some cars also use vacuum instead of, or as well as, centrifugal to give advance based on revs. For that the vacuum is taken from the venturi rather than from the manifold side of the carb.

[@Paulman50]

When cruising with the throttle partly open the fuel mix is very lean which takes longer to combust, so the vacuums rises pulling the disturber plate to 40° advanced, hence the ignition still happens at 34° and that is why the motor does not ping.

[@HappyBloxx04]

Clear instructions , thank you for sharing

[@D3Sshooter]

My pleasure

[@bentleynut1648]

Steve. I just spent a couple of hours watching a bunch of your videos on ignition timing. Absolutely fantastic videos...incredibly informative and I love your detailed and thorough explanations. Too often people on KZbin try to teach but have absolutely no skills at doing it, and don't explain the rationale of why things work the way they do. However, you have no such problem. Quite the contrary....one of the best teachers I have ever come across. Congratulations. I guess I only really have one question concerning timing. I really don't understand the purpose of vacuum advance and the situations it comes into play.....and how the vacuum advance works in conjunction with the mechanical advance. Does it create advance in addition to whatever mechanical advance is already present, does it cut in at a particular level of vacuum. Does it work when mechanical advance has shortcomings. What are the typical kinds of scenarios when you need extra advance which you don't get through mechanical advance. if you can answer some or all of these questions that would be great or if you can point me to a webpage that really explains it well....many thanks

[@D3Sshooter]

Thank you for the comments, The principle is very simple. The faster the piston moves up and down ( higher RPM), the earlier the fuel/air mixture needs to be ignited. Just because the burning time of that mixture and its peak explosion power is all ways a fixed time ( for a specific AFR). No matter how fast the pistons move. Thus, if we had no mechanical advance for high RPM's then the fuel would ignite at its static advance ( lets say 4 degrees). This would mean that the piston is way past its TDC and on its way down when the fuel explosion is at his peak, hence we lose power. With the mechanical advance (bob weights in the distributor), the centrifugal force becomes more forceful while RPM's increase. Thus the bob weights fly further out due to that centrifugal force. And by doing so the ignition moment is advanced in such a manner that the ignition of the fuel air mixture is earlier so that the max explosion power of the ignited air/fuel mixture comes just after TDC.. The mechanical advance regulates the time of ignition based on the RPM's. Higher RPM's means more centrifugal force on the bob weights, means more advance. Now lets talk vacuum advance, assume the engine is running at a steady 3000 RPM ,lets say cruising along the highway. The bob weights do their job as explained but are at a steady advance. Now we want to accelerate or clime a hill, in both cases the engine has more load and we depress the throttle. This causes a higher vacuum in the intake manifold ( more engine load means more vacuum). Meaning that more fuel is needed and sucked into the engine ( Low Air /fuel ration - AFR). Now the mixture is far more rich ( lets say AFR 11/1) versus cruising (lets say AFR14/1) as the acceleration pump will have injected additional fuel and the throttle is far more open. This means that the air fuel mixture is now having less oxygen and more fuel and the burning process is slower. The result is that the maximum power of the burning is past TDC . By using a vacuum advance ( vacuum from the intake manifold to the distributor), the ignition moment is further advanced in order to deal with the new mixture burning time. thus an earlier ignition. Once we have accelerated or are over the hill, the vacuum decreases in the intake manifold ( less load on the engine) and as a consequence the AFR goes back to normal (14/1). At the same time the vacuum advance on the distributor drops and we are back to the normal bob weight advance... In a nuttshell: -Static advance is a low RPM ignition time adjustment as the bob weights ave no effect - Dynamic advance is a mid to high RPM ignition time adjustment provided by the bob weights -Vacuum advance provides more temporarily advance when the engine is under load I hope that this helps

[@bentleynut1648]

@@D3Sshooter Thanks so much for a clear explanation.

[@paulmuff9883]

An excellent explanation many thanks😊❤it

[@carlbickerstaff5229]

Hi My friend, learning a lot from your videos, Thank you. One question is when you set your 10BTDC initial/static timing and then you connected your manifold vacuum to check your dynamic timing, Did your advance increase automatically at at idle when you connected the vacuum?. If so what would you expect in advance at 1000RPM at 10BTDC, through vacuum connection.

[@D3Sshooter]

That is correct, when you connect the vacuum even on idle running it can advance the ignition

[@sidneybolt1099]

That is a brilliant clear and conscience video. Out of interest what are your thoughts on ethanol additives and timing?

[@davidbattye7886]

What an amazing tutorial. Thank you.