with out taking an hour, straight to the point...Thanks

Maybe that wasn't the car? Need to consult with Al's wife Peggy on this one. ;)

@@thisisyourcaptainspeaking2259 savage...😂

Not my old Mopar's..Mopars were always tighter and rattle free than GM/Ford..unless you only owned 400,000 beaters that were slapped with new paint!

@@wheels-n-tires1846 An old timer once told me: If it smells like fish make it a dish. If it smells like cologne leave it alone.

@@MrTheHillfolk haha. Love it. Always avoided the gals with too much cologne.. What they trying to hide...

Did you go through this issue with your corolla? I'm having issues with my ke55 atm. when advancer plugged into port. the car dies under accelleration. when unplugged completely and port blocked... car runs fine.. lost..

my 1987 Honda CRX came from the factory as manifold vacuum. Had many people tell me to change it to ported instead of manifold. Pretty much ran the same at cruise, but at idle it was terrible, and would start overheating because of how hot the headers were getting on ported vacuum (about 5 or so degrees of timing (no vac, no mech) ), manifold vac would put it at around 20 degrees of timing (vac timing, no mech) and idles incredibly smooth

@@cmdr_scotty yep. My engine cooled down and ran super quiet when i switched to manifold.

Ford used ported in the 60's so......

@@yeboscrebo4451 same with my 350!

Exactly.

Yeah, uncle tony is wrong on this one. Listen to the actual automotive engineers describe the purpose of manifold vacuum advance. Tony has it backwards

@@yeboscrebo4451 link?

@@theungoliant9410 I’m sorry I don’t have one. You’ll have to run a search on the subject. I’m sure it won’t take long to find - it didn’t for me when I dug into the subject. There were two engineers in particular who have written extensively on the subject. If I remember correctly, one of them was a former GM engineer. Very interesting information

Same thing ... I switched to manifold and it's suddenly running so much better, it's unbelievable. Idles perfect, and you you tap the throttle, it just wants to go. For 40 years I've always done manifold from American Chevy 350s, Ford 289s, most European cars. Today many advice ported so I've been having a go at that. Nope. just doesn't work for a normal daily driver car with traffic choked roads in my hot tropical country.

@@theungoliant9410 kzfaq.info/get/bejne/j5xpgqpzx5ard6s.html

6 of one half a dozen of the other.Your description is pretty spot on i think. I remember having a '71 ford fe that had a coolant temp vacuum switch that when coolant temp got to a determined level it would route manifold vacuum to the dist. in order to increase timing and raise idle speed.That car detonated like mad on any kind of a part throttle load and started my education of vacuum advance. I remember trying so hard to keep the vacuum advance and tune out the detonation cause why I don't know.... because i was giving up maybe a mpg in fuel economy i guess LoL

2-3 MPG and a Fan Clutch on the street almost the same. Big difference on MPG added up.

I just made the switch to manifold on my 72 f350. Of course I had to make plenty of adjustments with timing but it was far superior to ported. The first thing I noticed was how quiet it was on a cold start. The engine ran much better and my mpgs went up by 3. I just don’t get why you’d want to run ported

One thing Tony doesn’t mention is, retarding timing under throttle can prevent detonation which can be a good thing in a performance engine. I run manifold vacuum and got a smoother idle and it stopped pinging at WOT.

I get that too, far superior performance and driveability on manifold vacuum. This debate will continue on, at the end to each his own. I'm happy always with manifold vacuum.

No. Lots of timing at idle creates heat.

correct. At idle, It will run smoother, cooler, create higher vacuum and run leaner increasing mileage.

Tony couldnt you find a busier😅 street to film on?

You, sir....... are correct.

DUI recommends manifold in their literature. How many of those 14 degrees ported vacuum advance are you getting at high speed/low load cruise? At low load, manifold vacuum is high and ported is quite low obviously. Run two gauges at once to validate. Seems like you could be getting more mpgs out of your cruise with more timing, manifold timing.

WTF? LOL

Baaark

@@AustinRBa could be they ignited an advancement

Tell your mom i want my gauge back dammit...........

I may know your mom

Desmogging meant switching back to manifold vacuum

Well said Ed. Full manifold vacuum is the best way. I think ported started with the Clean Air Act in 68.

Ported vacuum is pretty low just off idle and manifold vacuum is pretty high just off idle. You’re getting much more advance with manifold in that situation. It’s not just idle where the difference is. In fact, most vacuum canisters I’ve come across don’t start advancing timing until about 5 hg. So if your canister is connected to ported and you’re in light cruise with those throttle blades barely cracked, you’d be getting zero advance. If you were connected to manifold you’d be getting all of it - like you should.

Ah, yup. I think you nailed it. That explains the purpose of those (pvc looking coolant switches) perfectly. I do believe, you are spot on. All that foolishness should be bypassed and we should take our vac right from the intake in the first place.

It’ll only overheat if the manufacturer didn’t design enough static advance in, or the idle jets pushing the whole lean burn thing way too far.

I had a 75 Ford Granada with 302 that had that system smog pump , EGR valve and vacuum hoses everywhere if you took one or two off and did not know where they went your in trouble for sure . It has several water temp sensors with vacuum hoses hooked to it when it got to the set temp it would open and send more vacuum to advance the distributor more timing kinda of a neat idea .

The demonstration was hardly relevant

@@yeboscrebo4451 Hows that??? For people who are unfamiliar with vacuum advance, don't understand it, or might be 'visual leaeners', its totally relevant. How could it not be???

@@wheels-n-tires1846 because the distributor is only part of the symbiosis and doesn’t operate on its own so showing what happens in a disconnected distributor is hardly a comprehensive teaching aid. People think that you can just switch between ported and manifold and “see which one works best”. Wrong. If you switch between one or the other, the initial timing may need resetting, the mechanical timing curve needs resetting, the vacuum advance canister needs to be adjustable and set correctly and finally, even the carburetor may also need adjustment to achieve results. Uncle tony failed to explain WHY time is needed as certain inches of vacuum or certain rpms, he just pointed to a dizzy and said “look, see”. Sorry, even knowledgeable dudes like uncle Tony have crusty ideas they’ve harbored for years that are just wrong.

@@yeboscrebo4451 Lots to unpack there...so first, in other videos hes talked about timing and carb relationships. This vid wasnt about that. It could really be condensed into "see, using this port, good. Using that port, its working backwards, thats bad." Or.... "this shows exactly what happens when you hook it to the wrong hose"... Its meant at a 4th grade level for folks who know little or nothing about distributors, advance systems, carburetors, etc... And Tony certainly wasnt saying you could switch back and forth between ported and unported to run your vacuum advance distributor. Thats idiotic, and nobody that has a clue thinks that. Not sure where you got the idea that anyone thinks that!!! That might be the silliest statement Ive heard on YT in a long time...so its pretty bad!! So anyway, while youre right about the finicky relationships of timing and carburetion, this vid didnt intend to address that. Why does he have to address everything in each video?? Maybe try watching others. Id imagine theres HOURS of Tony on here explaining timing, curves, carburetion, etc. So if you expected it to give a thesis-level dissertation on that relationship and it's details, well guess youll just hafta stay dissappointed, because this vid, and frankly the whole channel seems to be more about basic info and explanations for beginners, or people who only have experience with newer cars and systems. Your conclusion that the old timer is dumping old and incorrect theory on here is whats wrong. I read and used Tonys knowledge for years and years...decades before he ever had a KZfaq, and can say that I put together a half dozen street/strip Mopars with that knowledge, and they were better and faster because of it.

@@wheels-n-tires1846 wow that’s a lot of words to not actually refute any part of my comment. Did you ever “unpack” the subject matter of the comment i made? Not sure where I got the idea? Have you read the comment section? Lol. As I already explained, the demonstration was not relevant precisely because it was overly simplistic. To explain the difference between ported and manifold vacuum, it’s not good enough to have a dizzy, removed from the engine, and expect to illustrate the relatively complex interactions between all three forms of advance timing. You can’t just say “look the advance mechanism is moving here on manifold and here on ported” because each case requires changes to the other two forms of timing advance. Just the fact that he did not acknowledge this interaction is indicative of his misunderstanding of the benefits of manifold vacuum advance. It seems like uncle Tony just gotten stuck on the teenage hot rodder “more timing equals faster” approach without every revisiting this idea in his old age. Your better off reading what the actual engineers had to say about it than an old hot rodder stuck in his ways.

I thought I was the only person crazy enough to tune the engine on the roadside....lol

Brian J. Medina your math is lacking skills

Meh. Been doing that for years

@@Welcometofacsistube holding a sign? Lol

@Curtis Fleabag I'll only do that with a homeless and hungry sign in my hand. Not a distributor lol

Yes ported it runs hotter so it will burn off the fuel more although in stop and go traffic in the summer you can get into trouble running ported . I ran ported and I could get 14.7 or more on the AFR gauge idling on manifold I would stumble out past 12.9 or so less timing the leaner it is more timing the richer it is problem is the distributor is not tuned for manifold vacuum a adjustable pod is a must .

On my old Porsches I always ran mechanical advance but on my Thunderbirds I always stay manifold.

Yes, that’s what manifold vacuum advance gives you, not ported

You can also drill a small hole in the front throttle plates, this will allow you to bring the idle screw down to cover the slots in the base plate. If you go any higher on cam profile. Another trick to let a little more air in was to adjust the screw on the secondary shaft to open it letting more air through and accomplishes the same thing. Either will let you drop the Idle screw down to function.

Me either.

Definitely not just you! I had to zoom and stare and rewind a little.... finally saw it. Phew!

We are not alone

Exactly. "When you need it most-" it was *never there* in the ported scenario- how can it be "taken away?!"

From what I can tell, you are correct. Notice around 4:58 as UT releases pedal, i.e. cruise condition (minimal fuel, somewhat high rpm) the vacuum advance can be seen to go away. But actually, you want mechanical and vacuum all working at that condition as the low cylinder filling and small amount of fuel need max ignition timing. So taking away vacuum advance at the condition, takes away much needed advance. The timing gets taken out during accelaration because cylinder filling increases so a faster ignite happens as a result of the richer mixture. From all the reading plus some testing I've done, I think the issue is that when hooked to manifold going from ported, idle timing goes up too high, so the distributor gets pulled back to end up at the same 12-14° idle timing when it was on ported, but now the vacuum is adding some of that idle timing. But that then limits the higher rpm timing because the mechanical is now down from 12-14, to probably 4 or so (rough numbers for illustration). So when acceleration is applied and vacuum drops, the mechanical is lower than it was when ported as the distributor was pulled back to compensate for the extra that manifold gave it at idle. So if we go back and set timing with vacuum port plugged off, and set say 12° purely mechanical, then plug in manifold vacuum and timing goes up to say 25 (rough number)... Instead of pulling back the distributor, leave it, instead, lean out the idle mixture screws and turn out the idle speed screw. By lowering rpm in this way, it should reduce some of the mechanical advance. Or so goes the theory that David Vizzard puts forth. Effectively, idle timing can be fine on ported but at cruise you want manifold advance to get that high timing number. That's the theory anyway

I think 🤔 the ported was a emissions thing i tried both on my 390 ford and on ported it ran good and the AFR was easy to get 14:1 especially on the Fwy only it woukd get hot 🔥 in stop and go idling traffic in the summer the exaust was 50 percent louder and at startup i would have water vapor coming out of the exaust . On manifold it was alot richer and i would need jet down a size or so alot harder to get perfect AFR usually be around 13:20 ish idling and 13:80 or so on the fwy but if was 50 percent quieter exaust and did not get really hot in traffic . Alot of people say the factory never used full manifold ?. I think before 1975 they did on the valve cover it has a low initial timing like 6-8 degrees if it was ported it would or should say 14-16 degress ...

@@TheThirdWheel618 All of my older vehicles used full manifold vacuum advance except a 1973 Dodge Dart with a slant 6. Once I bypassed the OSAC valve and gave the vacuum advance can full manifold vacuum, the engine ran cooler and more efficient. Better MPG's, better drivability, better cold starts.

@@muziklvr7776 Yeah i think before 75 for sure it was all full manifold Ford had a valve that operated by engine temp you were on ported untill the engine reached a certain temp say 200 then it would shut the valve off and it would go to full manifold to cool the engine down ???? That says it all the factory knows they can reach better AFR with ported at idle but it creates a lean condition so they came up with the valve idea .

The demo is TOO simple. He showed what happens to the dizzy when the advance canister is hooked up to ported or manifold. He didn’t adequately explain why you need different timing at different levels of load or rpm. For a more comprehensive demonstration, the dizzy needs to not be removed from its symbiosis with the other parts of the engine. A better approach would be to show two different vacuum gauges one from ported and one from manifold at the same time. Then, take the engine through different circumstances in load and rpm to show what is happening with the timing. Uncle tony was able to explain the opposite of the truth because his demo was overly simplistic.

Or just take the same engine and tune for ported on the dyno then tune for manifold and see which one wins.

There would be zero difference on a Dyno. You don't leisurely cruise on a Dyno, you crack it wide open under a heavy load--- ported or direct manifold vacuum are BOTH going to give exactly zero added degrees vacuum advance, no partial throttle runs on a Dyno. Glad I drive a truck and don't drive a dyno

@@hiswordheals9710 From what I've read, most modern vacuum advances will give you 12 to 14 advance and mechanical advances will give you 12 to 14. As the vacuum drops, the mechanical advance makes up for it depending on both timing curves. Some mechanical advance only distributors will go as high as 28 to 3,000 rpm or even higher, but mechanical advances are more typical of motors built for heavy load applications such as tall deck 366's or tall deck 427's (extra oil ring in the pistons to handle higher advance/compression/heat at higher RPM's under heavy load). Some vacuum advances are also adjustable so we can play with the timing curve. We know that as RPM's increase, the vacuum increases even as your primary throttle plates open up but as your primary plates open up more than half way, the vacuum begins to drop. I'm spitballing here, but I think the vacuum begins to drop as the primary throttle plates open up past half way but if your engine RPM's are in the high 2000's or higher the vacuum is still mostly maintained so it doesn't drop by much. It's when the secondary 4 barrels (throttle plates) open up that the vacuum tends to crater. Your vacuum advance drops to zero on a SBC with your carb fully open up to around 4500 but then slowly picks up past 4500 advancing minimally by 4 degrees or so around 6500 RPM's. But then, if you are pushing a motor to these RPM's on a dyno, it's built for it. This isn't to say vacuum advances won't be used on the street pushing these revs, but the chances are more likely that a motor on a dyno pushing 6500 or higher is built to race with a lock out distributor with all of it's advance at startup. The type and size of your carb also effects vacuums. A Rochester for example, has much larger secondary venturi and throttle bores than primaries so as your secondaries open up on a Rochester, the ported and manifold vacuums drop lower and more quickly than equal sized throttle bores. Same holds true for larger CFM carbs such as a 750 on a 350 sbc, the vacuum off your port will be lower on a 750 compared to say a 600 CFM carb because your venturi and throttle bores are larger on a 750. Hi performance cams, ported heads and high rise intakes will also drop your vacuum (substantially), but that's for another conversation. 🙂

If you didn't already know this, then you are not a hot rodder!!!

@Jonny longfella Cause it'd be possible? :)

No it takes a really dumbass to complicate it in their head more than it really is! If you need it dumbed down to grasp it!!

Part throttle acceleration is the domain of initial/mechanical but mostly mechanical advance. Ported timing is redundant in this regard - it’s doing the same job as mechanical timing just a more limited range. Use manifold advance and you free up the vacuum canister to do a different job that ported is unable to do - advance timing at high vacuum/low load situations.