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  #16  
Old 11-13-2008, 12:06 AM
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Originally Posted by Opossum
OK Bear I'll answer this one for ya, pay attention.

First, these days a real honest to god racing engine won't have a vacuum advance because it uses a computer to control the timing.

Back in the day before computer controlled timing, race engines didn't (NASCAR still dosen't) have a vacuum advance for reliability, because it has very little effect on the performance there looking for, and would be to hard to make work well (the throttle is open to far at idle, and these engines produce very low vacuum). Many race engines are designed and tuned only with full throttle performance in mind. At full throttle the vacuum advance is irelevent because there is very little vacuum.

These engines also don't idle well, produce good low end torque, have good throttle response, or get good mileage.

They also don't use power valves, vacuum secondaries, hydrolic lifters, pump gas, or streetable torque converters.

There not asked to drive around in heavy traffic, haul heavy loads, deal with low stall converters, and drive power stearing and A/C pumps.

Hope this helps Bear but I suspect it won't.

I've been doing this for a living for a long time and have been fortunate enough to work shoulder to shoulder with many professional racers including a top fuel funny car champion. My personal passion and business is built around providing my customers with the most capable street cars and trucks, to fit there needs much better then any factory can provide.

Ya know if you didn't have that pic I'd think you knew better and were just being argumentative.

When I look at the picture in your sig it is obvious that you are confused. I see a tri power, these were never a good idea and you will never see any honest to god racing engines running a tri power. And I see a very cheap ignition system. How do you even get that thing started? I could go on but those are the biggies and tell me all I need to know about wether or not you know what your talking about.

From what I've read in other posts your very knowladgable on classic fords and probably know more than I do when it comes to restoring a factory ford. At least when it comes to what came with what, but I'll still make it run better.

Now your wondering, what's wrong with tri-power? The problem really isn't tri-power per se, it's the fact that there is (no one has been able to do it yet) no good manifold to make it work well. For a street engine you need a good dual plane manifold. This is to hard to do while providing for the three carbs. It in theory can be done but the manifold would be rather tall and complicated, making other options like dual quads a better choice. Or my favorite a big single 4V with four corner idling on a medium height dual plane manifold with a large volume.

I'll be in the Union area the weekend after thanksgiving, if you would like I could stop by and make your vehicles run better?
Ok, then explain the 427-8V with a dual point mechanical advance only dist. way back in the 60s?
 
  #17  
Old 11-13-2008, 12:45 AM
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benshere;
I am not aware of veturi vacuum ever being used to control timing, Only to control secondaries and variable venturies. At any rate I don't beleive it would be a good idea. The cetrifigal function of the distributor does a good job of contoling timing changes for RPM, but it is an intriging idea I don't think anyone has tried it. I could be wrong.

You don't want to pull timing out as venturi vacuum increases, as RPM increases timing should increase, so having venturi vacuum and manifold vacuum offset each other would be a bad idea. It could work well if they complemented each other. That would require using two seperate vacuum cans both pulling in the same direction on the distributor base plate. Also remember that primary and secondary vacuums would have to be included for it to be accurate. I know of no carb that has a vacuum referance from the secondaries.

Thanks for backing me up on the tri-power. There cool as the show but that's about it.

As to FI on the Mach, the hardest part is finding the ideal manifold. If I was asked to do that job I would grab a good aluminum dual plane and add some injector bungs and fuel rails. Then use a throttle body on top and the Accel Fuel injection computer.

Colo79Ford - Thanks for backing me up. You make a good point about the points. I keep forgetting that some people still have them. I believe '75 was the first year for the Duraspark, a darn good upgrade. I personally don't see any reason for anyone to run points anymore if that is the problem please just re[lace them with a pertronix flamethrower unit. Ya know, if you still run points you should upgrade it anyway.

And Bear, That one is the easiest to answer. Because they didn't know any better.
 
  #18  
Old 11-13-2008, 01:35 AM
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It strikes me that I should explain why we have timing advance. I believe that once a person knows how things work and why there built the way they are, the rest becomes self evident. I got some time so here goes, pay attention Bear.

During combustion the fuel/air does not explode it burns this is important because it takes time. That is why we have a timing advance first based on rpm, as rpm increases the time it takes to reach tdc is decreased to the spark/burn must be initiated earlier. Now the speed of that burn depends entirely on the amount of pressure in the cylinder. This is why high compression engines use less timing, in fact it's why we have compression.

Now we get to vacuum advance, the amount of vacuum in the manifold has a direct impact on the cylinder pressures. This is why we have throttles and how they work, the throttle controls manifold vacuum. Anyway more vacuum creates less cylinder pressure reducing the speed of the burn making more timing nessasary to acheive the best performance.

If there is no vacuum advance the timing can only be tuned asuming the fastest burn making all throttle positions less then full open less efficient/powerfull.

Any questions?
 
  #19  
Old 11-13-2008, 02:58 AM
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Originally Posted by Opossum
It strikes me that I should explain why we have timing advance. I believe that once a person knows how things work and why there built the way they are, the rest becomes self evident. I got some time so here goes, pay attention Bear.

During combustion the fuel/air does not explode it burns this is important because it takes time. That is why we have a timing advance first based on rpm, as rpm increases the time it takes to reach tdc is decreased to the spark/burn must be initiated earlier. Now the speed of that burn depends entirely on the amount of pressure in the cylinder. This is why high compression engines use less timing, in fact it's why we have compression.

Now we get to vacuum advance, the amount of vacuum in the manifold has a direct impact on the cylinder pressures. This is why we have throttles and how they work, the throttle controls manifold vacuum. Anyway more vacuum creates less cylinder pressure reducing the speed of the burn making more timing nessasary to acheive the best performance.

If there is no vacuum advance the timing can only be tuned asuming the fastest burn making all throttle positions less then full open less efficient/powerfull.

Any questions?
Keep explaining, I need to know how I won a bunch of local championships, quite a few regional championships and several divisional championships, plus two nation high point championships and set 3 different speed records in two different racing sports. You can't teach me anything about engines and how they work. So don't bother. Every time you start typing I know you are a self made expert that really has no clue about engines and getting preformance from them an the street or on a race track.
 
  #20  
Old 11-13-2008, 09:28 AM
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tripower & venturi

I would like to have another shot at the tripower setup. The vette was the first setup I ever worked with and I had a lot to learn. Yes the end carbs had acc pumps and only the center had idle adj screws. Bo Laws (orlando fl) was campaigning a 67 fastback in "C" and "D" sports back then and it was he that suggested a single 4 with the edelbrock. It was a 390/400 version with oval port heads and a hyd cam. Only difference was Quadrajet or tripower, which changed the classes. If fact, he needed a tripower setup to run at a G'ville meet so he could run his car in "C" ---it actually had a slower time to run against than "D" sports. He held the nat record in both---same car! Strangely enough, the car I used to guage my performance against was my brothers 69 428CJ . Properly tuned, I cant say that the tripower wouldnt do better, but for sure it wasnt better under 3500-4000 and only marginally better above----not enough to catch up to the 4bbl setup. Sure had lots of fun with the CJ

opossum--the sources would fight each other at the dist diaphram. Whatever the sources, they are applied to both sides of the dist diaphram and the strongest will win, venturi increases with rpm like the centrifugal. I cannot see a real benefit except that it could be used to overcome the manifold vacuum at rpm and pull back timing to the power curve as rpm increased. I dont understand all that I know about that except that manifold vacuum is disappearing by then anyway and the crank and centrifugal is all in (presumeably for the 36-38 power curve). I am not saying that venturi was a part of the advance strategy for sure, just curious what sources are used for the double diaphram dists. My mach has a plastic cannister under the dash that has something to do with timing and what bern said on his 351C somehow rings a bell The FI setup for my mach is kinda on a rear burner--tx
 
  #21  
Old 11-13-2008, 11:31 AM
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Originally Posted by benshere
I would like to have another shot at the tripower setup. The vette was the first setup I ever worked with and I had a lot to learn. Yes the end carbs had acc pumps and only the center had idle adj screws. Bo Laws (orlando fl) was campaigning a 67 fastback in "C" and "D" sports back then and it was he that suggested a single 4 with the edelbrock. It was a 390/400 version with oval port heads and a hyd cam. Only difference was Quadrajet or tripower, which changed the classes. If fact, he needed a tripower setup to run at a G'ville meet so he could run his car in "C" ---it actually had a slower time to run against than "D" sports. He held the nat record in both---same car! Strangely enough, the car I used to guage my performance against was my brothers 69 428CJ . Properly tuned, I cant say that the tripower wouldnt do better, but for sure it wasnt better under 3500-4000 and only marginally better above----not enough to catch up to the 4bbl setup. Sure had lots of fun with the CJ
Yes, the idle curcuit in the end carbs is very important too. You need to remember that the car I had the 3X2 on was a 1969 Torino Cobra Notchback that weighted ready to roll just over 3000 pounds and had the 4.30:1, 31 spline rearend with slicks and a toploader 4 speed. The car carried the front end a car length on launch and in the early 70s, very few truly streetable cars would do that.
 
  #22  
Old 11-13-2008, 05:36 PM
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idle ckts/ diet!

The vette end carbs did not have an idle circuit, only the center. I got embarassed, big time, over that by a good friend/Chebby fan. The vette was wicked on the street, even though it was only the 400 hp version. (tripower, oval port heads, hyd cam) It had just the right amount of power so you could control launch (on street tires) pretty easily. All you could see from inside was those front fender "wings" reaching for the sky! The 69 CJ gave it an excellent run, only disadvantage was at the line and a little bit down the strip. I got so tired of hearing "no wonder you beat me, look at what you got" from others that it wasnt any fun.

I sold the vette and bought a 66 comet cyclone gt (390, 4 speed, fiberglass hood etc. with the full intention of putting in a 428 CJ or even a 427 MR---if I could find one. I did my usual---procrastinate, and never did.

As I recall ole bro's CJ (cyclone, FB) weighed in dry at 3450. The formal coupes were about 50# lighter. You must have put your torino on a good diet-----. The 66 cyclone weighed about the same as the 69's. With a little bit of imagination, I could have had a 454 W/CJ or MR heads based on the 427 block-----oh well, hindsight!

As far as this 3X2 or 4bbl thing, I really cant contribute much. I would like another shot at the vette tripower----which will never happen
 
  #23  
Old 11-13-2008, 06:54 PM
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Originally Posted by benshere
The vette end carbs did not have an idle circuit, only the center. I got embarassed, big time, over that by a good friend/Chebby fan. The vette was wicked on the street, even though it was only the 400 hp version. (tripower, oval port heads, hyd cam) It had just the right amount of power so you could control launch (on street tires) pretty easily. All you could see from inside was those front fender "wings" reaching for the sky! The 69 CJ gave it an excellent run, only disadvantage was at the line and a little bit down the strip. I got so tired of hearing "no wonder you beat me, look at what you got" from others that it wasnt any fun.

I sold the vette and bought a 66 comet cyclone gt (390, 4 speed, fiberglass hood etc. with the full intention of putting in a 428 CJ or even a 427 MR---if I could find one. I did my usual---procrastinate, and never did.

As I recall ole bro's CJ (cyclone, FB) weighed in dry at 3450. The formal coupes were about 50# lighter. You must have put your torino on a good diet-----. The 66 cyclone weighed about the same as the 69's. With a little bit of imagination, I could have had a 454 W/CJ or MR heads based on the 427 block-----oh well, hindsight!

As far as this 3X2 or 4bbl thing, I really cant contribute much. I would like another shot at the vette tripower----which will never happen
You mean a Cyclone like this?


With this engine?
 
  #24  
Old 11-13-2008, 07:13 PM
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torture

You sure know how to hurt a guy Yep, like that one except mine was yellow with a black stripe. Wrap it up---I'll take it . Now lets see-----427 block, 428 crank, alum MR heads, 427 adjustable rockers, Alum intake maybe 2X4/3X2/1X4, TKO 5 speed-----. And lastly, a new place to live since wifey will probably go ballistic!
 
  #25  
Old 11-13-2008, 07:17 PM
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The pic is from 1968 at McConnell AFB in Wichita, Kansas. Traded it in on this.
 
  #26  
Old 11-13-2008, 07:27 PM
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scoop

I dont recall bro's 69 cyclone having a hood scoop---guess I need to dig out a picture from somewhere. Also think the cyclone had decals where the "snakes" were on the sides.

I suppose the shelby upper arm relocation works on these as well. Should really, I think the 69/70 mach and torino/cyclone all had about the same front clip.

After I got rid of the cyclone, I got a 69 500 XL, 390 which I wound up putting in the 460 CJ motor in. (they didnt make a 460CJ, I did).
 
  #27  
Old 11-13-2008, 07:32 PM
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The hood scoop was for the Ram Air. The non-Ram Air had no scoop.
 
  #28  
Old 11-13-2008, 08:04 PM
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ram air

Forgot about that. Cyclone didnt have ram air. We "shade treed" a ram air setup with steel flex to the windshield fresh air plenum. Worked great. Brother ran a local friend of a friend with lots of coins that had several Hurst 455 olds of that era. We beat all of them. He did in numerous chevelles, cameros, Magnums (3X2) and GTO's. I egged on a race with a new 455 judge (I was in my 66) from a kick down just to get the CJ in the race. I did, he did, and he did out kick the judge. Now I do realize that all those may not have been a good indication of all those brands--but it was fun.

The nostalgia has been fun But I better go get my nappy poo so I can get something done tomorrow. Really getting interested in my 70 Mach---again! Later---
 
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