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2bbl to 4bbl swap
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oldwood
Posted 2014-08-13 11:14 PM (#452840)
Subject: 2bbl to 4bbl swap


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I have a factory 4bbl carb and manifold from a '60 Dodge. Were there any internal engine differences. I thought about putting this 4bbl on my '59 plymouth. Both of these cars had the 318 poly.
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60 dart
Posted 2014-08-14 12:26 AM (#452850 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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no , bolt it up ----------------------------------------later
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1961plymouthfury
Posted 2014-08-26 3:29 PM (#454266 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap


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I am thinking about converting from 2bl to 4bl carburater on my current '61 . I am also looking at converting to electronic ignition. My dad says the car is not running as good as my other '61 I believe it could be the following, spark plugs are fouled bad distributor , or cap or the fuel lines need to be cleaned out or replaced. The last time I put fuel in it I put marvel mystery oil in the fuel tank then put fuel in the tank .
I used to do this with my other '61 but I put the marvel mystery oil in every other fill up.
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d500neil
Posted 2014-08-26 7:32 PM (#454288 - in reply to #454266)
Subject: Re: 2bbl to 4bbl swap



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If anyone is going to upgrade his engine to a 4-bbl carb, he had better get his distributor re-curved, and get a 4-bbl compatible
vacuum advance with it, too.

A 2-bbl dissie will not allow the engine to use the extra fuel that the 4-bb carb will provide...also, the 2-bbl V.A. will cause
too much Total Advancement to occur at high speed cruise mode, which will cause detonation (pinging).








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1961plymouthfury
Posted 2014-08-26 7:47 PM (#454290 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap


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My other '61 was a 2bl but my dad upgraded to a 4 for better performace . He will know what to do he knows these cars well .
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60 dart
Posted 2014-08-27 12:07 AM (#454311 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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A 2-bbl dissie will not allow the engine to use the extra fuel that the 4-bb carb will provide...also, the 2-bbl V.A. will cause
too much Total Advancement to occur at high speed cruise mode, which will cause detonation (pinging).

maybe thats how it works out west of the mississippi but not here . i've used 2 , 4, and 6 bbl's using an old single point dist from a 2 bbl motor (oem stock on bertha). the only thing that changed was less fuel mileage
and better performance . it even started better with the 6bbl's . not one ping at any time ! --------------------------------------later
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d500neil
Posted 2014-08-27 3:35 PM (#454393 - in reply to #454311)
Subject: Re: 2bbl to 4bbl swap



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Oh, yeah, Chuck.....otherwise the factory would not have had different dissies installed on different engine applications.

The internal settings/advancements were very different from the 2-bbls to the 4-bbl engines (and AMAZINGLY so, when you
confirm all of the many different dissies that are installed in our cars).

I happened to drive to/from Tulsa with an (unknown, then...) inoperable vacuum advance.

(And I wondered why I was getting crummy MPG, on the highway driving...)

Our cars, even the 'performance' models, have VERY conservatively set up distributors....owing to the lowest common denominator-driver
and varying (-lousy) formulated gasoline...and owing to the fact that a real enthusiast driver already knew about having his car's
distributor be re-curved, for maximum performance and miles-per-gallon.

Yeah, a car might 'operate' with a non-functioning V.A., or a wildly inappropriate dissie/V.A., but to maximise performance
and MPG, the dissie should be re-curved and have light-weight return springs be installed in it, and its V.A. should
provide an additional, appropriate, amount (and not too-much) of advancement for sustained high-speed cruise-mode.....
to prevent detonation from occurring!


Because a 2-bbl carb can not provide as large of a fuel/air slug to the combustion chamber as a 4-bbl carb does, considerably-higher
timing advancements are dialed into a 2-bbl system, so that the fuel mixture can be ignited with the piston farther down in
the c.c., to burn as much fuel as possible.

54+ degrees of Total Advancement is not unusual in a 2-bbl car; that much advancement (you can compensate by reducing
the Engine's Initial Advancement to close-to-1/2 degrees...but that hurts your start-up performance)....will tend to cause
detonation, in a 4-bbl carb-car....at cruise mode.

Also, the RETURN SPRINGS (in BOTH the 2/4 bbl carbs...LOL...not)..., inside the dissie, are relatively very stiff, which slows-down the advancement rate, which keeps the engine advancement from reaching "Critical Mass"....and causing detonation to occur.

Chuck's engine doesn't "ping" BECAUSE the springing keeps the advancement-rate way-down, so that it might reach
the detonation-point only at very high speeds.

Again...the dissie is strangling the engine's performance, for the sake of all-around/varying-driver/gasoline/usage of the car.










Edited by d500neil 2014-08-27 4:31 PM
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Ray
Posted 2014-08-27 3:46 PM (#454394 - in reply to #454288)
Subject: Re: 2bbl to 4bbl swap


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d500neil - 2014-08-26 6:32 PM If anyone is going to upgrade his engine to a 4-bbl carb, he had better get his distributor re-curved, and get a 4-bbl compatible vacuum advance with it, too. A 2-bbl dissie will not allow the engine to use the extra fuel that the 4-bb carb will provide...also, the 2-bbl V.A. will cause too much Total Advancement to occur at high speed cruise mode, which will cause detonation (pinging).

 

Anyone know how a Pertronix conversion fits into this type of carb/manifold swap?

Thanks

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d500neil
Posted 2014-08-27 3:55 PM (#454396 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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A Pertronix does LITTLE to affect a car's performance, other than to create a uniform, reliably very-hot ignition spark.

That reliable hot sparking can positively effect the gas consumption efficiency, but, the Pertronix will not 'fix' any ignition timing aspects
that are already built-into the distributor and the Vacuum Advance unit.


This is my spare POINTS distributor that I keep (boxed-) inside the trunk, in case of a catastrophic Pertronix system failure...Pertronix
failures are not (at all) common, but in case such event does occur, your car will come to a 'screeching' halt, or will fail
to start up.





Edited by d500neil 2014-08-27 4:24 PM




(PICT1192.JPG)



Attachments
----------------
Attachments PICT1192.JPG (109KB - 124 downloads)
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ttotired
Posted 2014-08-27 6:06 PM (#454409 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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Just looking at your picture Neil

Do you have trouble looking at your computer screen?


Noticed the white out is all

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57chizler
Posted 2014-08-27 6:54 PM (#454414 - in reply to #454288)
Subject: Re: 2bbl to 4bbl swap



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d500neil - 2014-08-26 4:32 PM

If anyone is going to upgrade his engine to a 4-bbl carb, he had better get his distributor re-curved, and get a 4-bbl compatible
vacuum advance with it, too.

A 2-bbl dissie will not allow the engine to use the extra fuel that the 4-bb carb will provide...also, the 2-bbl V.A. will cause
too much Total Advancement to occur at high speed cruise mode, which will cause detonation (pinging).


You're really fixated on this distributor thing aren't you?








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d500neil
Posted 2014-08-27 6:55 PM (#454415 - in reply to #454409)
Subject: Re: 2bbl to 4bbl swap



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Glad you asked.....

The White Out is packaged with the Points Dissie, inside the trunk....along with detailed instructions....

WHY (I hear you ask...)?

Because, when/if your Pertronix craps-out, you'll need to install the Points-guy with its rotor oriented as close as possible to that of the position of the Pertronix's rotor (when you remove the dissie cap and discover/confirm the rotor's orientation).

As the rotor(s) can move around, on both dissies, you use the White Out to mark the Pertronix's rotor's orientation, on its dissie-case, BEFORE you remove the dissie from the engine.

Then, you "immediately" make a similar-corresponding mark on the Pointy's case, so that when Mr. Pointy gets installed, its rotor can be positioned/aligned to its case's White Out reference-mark (which, then, positions its rotor to the same/correct orientation, as formerly existed in Mr. Pertronix).

Simple, huh?






Edited by d500neil 2014-08-27 7:10 PM
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d500neil
Posted 2014-08-27 7:02 PM (#454416 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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You think?


I do.



Edited by d500neil 2014-08-27 7:03 PM
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ttotired
Posted 2014-08-27 7:25 PM (#454418 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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I do exactly the same Neil, but in engines where the distributor is gear driven, I also mark where "Mr Pointy" is pointing after it stops turning while lifting it out, that way, you have a start and finish reference mark

Makes life so much easier

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fenix
Posted 2014-08-27 11:39 PM (#454448 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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I used to carry White out in my emergency dizzy kit also, until one night there was no moon and i was all alone on that red dirt country road, in the pouring rain just three miles this side of the abyss (actually Social Circle, Ga. and if ya been there, abyss is most apropo needs no explanation), no flashlight, and just my luck, after 46 years, I had quit smoking just that afternoon ( something told me that would come back to bite me some night if my Pertronixified dizzy every croaked) and I had foolishly celebrated by tossing, tossing My Bic, tossing My Bic lighter, yep threw them both, the Bic lighter and those addictive Mild Seven Japanese cigarette's into a local Koi pond as sweet revenge for my lungs, come to think of it, that may have been what took out the Pertronix, cause those Koi ponds are few and far between around Mansfield, Newborn, and, Social Circle. Anyway, I always use a Chemlight or even Luminol, because there's always some pretty hefty blood residue around where i work on a motor.
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58coupe
Posted 2014-08-28 9:27 AM (#454492 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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Neil, you are only partly correct. Yes, playing with the mechanical advance rate can give more performance and possibly changing the VA total will help MPG. Yes, there are slight differences between the specs. on 2bbl and 4bbl dist. but on our old cars, not that much. Where you are wrong is in the part throttle cruise, there is no difference between the vacuum created in the engine between a 2bbl. engine and a 4bbl. engine running on the front 2 barrels. As soon as you open the throttle for more power and the vacuum in the engine drops below 10-12 inches, the VA is no longer even working. I'm not trying to get in a big argument with you but I have been doing this for a long time I am just trying to clarify some of your statements.
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57chizler
Posted 2014-08-28 2:35 PM (#454538 - in reply to #454492)
Subject: Re: 2bbl to 4bbl swap



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Pity the tens of thousands of souls who have performed 2-barrel to 4-barrel swaps without giving any thought to the distributor. They killed their motors without even knowing it. (chortle)
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ttotired
Posted 2014-08-28 6:19 PM (#454565 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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I am with 57chizler there

For optimum performance from your nice new 4 barrel carby, yes, re graphing the distributor is an excellent and relatively easy thing to do, but you could also say cam change is also necessary as well as a new exhaust ect ect ect

Can you put a 4 barrel on a 2 barrel engine, yep, will it go as well as if it was factory, maybe, but probably not, but you would be hard pressed to feel the difference

I think you will find that even the throttle linkages will be pretty close to in the right spot as well

Put it on and play with fine tuning later, if you have the engine out, then I would play camshafts ect but I wouldnt stress about it

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d500neil
Posted 2014-08-28 6:46 PM (#454567 - in reply to #454565)
Subject: Re: 2bbl to 4bbl swap



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Pity the tens of thousands of souls who have performed 2-barrel to 4-barrel swaps without giving any thought to the distributor. They killed their motors without even knowing it.


...AGREED!


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d500neil
Posted 2014-08-28 6:57 PM (#454569 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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The (one-) reason that you are incorrect, Mick, is that I had my car's OEM distributor be re-curved, for optimal performance
without pinging, as I've written elsewhere, including installing light weight return springs, and the improvement in acceleration with
the extemely-high 2.76 gear ratio is dramatic.

Unless and until you do the timing upgrade, you are merely speaking hypothetically, like John, above here.

Again, your cars' performance is being held back by the very conservatively-curved OEM distributors.

A 2-bbl dissie/V.A. with a 4-bbl carb does not (necessarily) ping because the heavy return springs in it hold-back the rate of its timing advancement, and it certainly is not allowing the engine to perform to its full capability.






Edited by d500neil 2014-08-28 7:12 PM
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Mopar1
Posted 2014-08-28 7:51 PM (#454582 - in reply to #454569)
Subject: Re: 2bbl to 4bbl swap



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Most engines could probably benefit from a trip to a shop that can dial in the dizzy & carb. As far as cam, maybe, maybe not. The 331 Hemi started as a 2 bl with small ports & valves. in '54 they added bigger ports & a 4 bl. In '55 they increased the size of the valves and bumped advertised C/R rom 7.5 to 8.5. Same cam is used on all of them.

Edited by Mopar1 2014-08-28 7:51 PM
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ttotired
Posted 2014-08-28 7:58 PM (#454584 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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No Neil

I used to re curve distributors pretty much weekly when I was an apprentice, so I am not talking hypothetically.

As I did say, you can put a 4 barrel on and it will work fine, but generally not as good as if it was a factory fit (correct cam, correct exhaust, correct distributor settings)

If the engine is out, I would address all of these, If it is in, I would do as much as I can without stripping the engine

The performance of the engine will be better by dropping a 4 barrel on over a 2 barrel and doing nothing much else, do the rest of it and
it will be better again

Then we can do a little bit more and give it electronic ignition and it will be a bit better again, then bigger valves and it will be better again and so on, just steps up the horsepower ladder, most things help, but unless your trying to get a set horsepower figure (say the original 4 barrel figure) straight off the bat, you can work towards it by doing a bit at a time

Thats what I mean, does it all have to be done at once? no, will it work if you just put the carby on? yes, will it be as good as stock then? no, can it be as good as stock? yes, if you do the rest of it

Stock is stock 4 barrel car not 2 barrel, without figures and as a general idea, just dropping a 4 barrel on would put you somewhere between 2 barrel performance and stock 4 barrel performance.


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1961plymouthfury
Posted 2014-08-29 3:02 PM (#454663 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap


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My father was the 1 who did the swap on my other '61 . I am not sure if he curved the distributor was curved I believe it was left were it was at
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58coupe
Posted 2014-08-29 8:12 PM (#454683 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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Neil, I say again you need to clarify your statements. Get in your car, stomp on the gas for brisk (or maximum) acceleration and the VA NEVER comes into play. Recurving the dist. for a faster mechanical advance rate does more good for acceleration than for cruise. When you are at part throttle cruise, the initial+mechanical+ VA all work together and can be as much as 50 degrees + and that gives good economy. Yes, I agree with you that recurving the mechanical advance to be all in at 3500-3700 rpm instead of 4500 rpm does help but you are not going to hurt your 2 bbl. engine by just putting a 4 bbl. on it. Of course, changing to a hotter cam changes things also,so as ttotired says, everything has to work together.
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Ray
Posted 2014-08-29 10:12 PM (#454692 - in reply to #454396)
Subject: Re: 2bbl to 4bbl swap


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d500neil - 2014-08-27 2:55 PM A Pertronix does LITTLE to affect a car's performance, other than to create a uniform, reliably very-hot ignition spark. That reliable hot sparking can positively effect the gas consumption efficiency, but, the Pertronix will not 'fix' any ignition timing aspects that are already built-into the distributor and the Vacuum Advance unit. This is my spare POINTS distributor that I keep (boxed-) inside the trunk, in case of a catastrophic Pertronix system failure...Pertronix failures are not (at all) common, but in case such event does occur, your car will come to a 'screeching' halt, or will fail to start up.

Thanks for the information. I purchased a aluminum distributor so I could install the Pertronix. I have no idea as to its origins - 2bbl or 4bbl -other than it listed as 1962. Is there any easy way to detrmine which it is?

Thanks

 

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Mopar1
Posted 2014-08-30 12:13 PM (#454721 - in reply to #454692)
Subject: Re: 2bbl to 4bbl swap



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Ray - 2014-08-29 9:12 PM

. I purchased a aluminum distributor so I could install the Pertronix. I have no idea as to its origins - 2bbl or 4bbl -other than it listed as 1962. Is there any easy way to detrmine which it is?

Thanks

 

Not unless there a complete list with applications, there are for early hemis, so probably on this too somewhere.
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57chizler
Posted 2014-08-30 3:21 PM (#454730 - in reply to #454569)
Subject: Re: 2bbl to 4bbl swap



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d500neil - 2014-08-28 3:57 PM
Unless and until you do the timing upgrade, you are merely speaking hypothetically, like John, above here.


Sorry, Slick, but you're the king of "hypothetical" here. My sarcastic reply above was aimed at those who speak only theory, not actual practice. Tens of thousands have performed 2 to 4-barrel swaps without the havoc you predict.

In reality, the difference in timing curves might show up on a dyno or at the drag strip but for the average "seat of the pants" driver they'll never feel the difference and neither will the motor from a reliability standpoint. (IOW, you ain't gonna melt pistons with a simple carb change)
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d500neil
Posted 2014-08-30 7:36 PM (#454748 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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Before I get to John's "Neener-Neener" nonsense (with him trying to sound important...oh well)...Rolland, to your questions:

There are three timing situations where your timing system can cause the engine to experience "detonation" (the rattling-sound that is heard upon acceleration).

Detonation happens when the sparking occurs while the the piston is too far down, inside the cylinder (timing is too far advanced).

Timing advancement controls the time that it takes to have the spark ignite the gasoline/air mixture, while the piston is still rising, during its compression stroke.

You manually set your engine's "Initial Advancement" (or: 'Crankshaft' Advancement), which allows your car to accelerate (rapidly, or not) away from its idle speed.

On our cars, the I.A. sweet spot is at about 8-10 degrees before top dead center is reached.

Beyond 10 degrees (deep), the fuel mixture gets burned too soon, due to the slow piston speed, and the pressure from the ignited mixture will hit the piston and be wasted, trying to shove the piston down before it reaches the end of its upward travel.

This situation is very inefficient and noisy, and can damage the engine.

Too little I.A. (like around 1-4 degrees) and the ignition process will continue too far beyond TDC, as the flame front 'chases' the piston down the cylinder, in the rapidly diminishing pressure of the combustion chamber.

The next situation that can cause detonation is the amount of Mechanical Advancement (and its RATE of advancement, that is built-into all of our distributors, in COMBINATION with the I.A. that we have set, above.

Detonation can/will occur (in a 4-bbl carb-car), at W.O.T., when the combination of the engine's I.A. + the dissie's M.A. exceeds about 36 degrees.

NOW, the factory, in its "American Manufacturer's Specifications Sheets" (see Page-9) lists the built-in distributor advancements for each of its MANY different distributors.

The advancement rates are VERY difficult to interpret, on that Page, but, they are expressed there.

Virtually all FWDLK disributors are CONSERVATIVELY curved (the lone exception: the 1955 Windsor V/8's IAZ 4001E, which has 28 degrees of built-in M.A.).

Simple mathematics will show that 28 degrees of dissie M.A. + 8 degrees of engine I.A. will produce 36 degrees of Total Mechanical Advancement ("T.M.A.").

At partial-start-up throttle, the I.A. is engaged, which can cause Detonation, if the timing is too far advanced (beyond 10 degrees, to be 'safe').

At W.O.T. (and/or during acceleration), the dissie's M.A. kicks-in, and that's where a lot of us experience pinging; when the I.A. + the dissie's M.A. together produces timing in excess of about 36 degrees of advancement.

The factory throws-in a lowest-common-denominator/Joe-Average-Driver factor, in all of their dissies (even, in the beloved IAZ 4001E, above), by its installing one (or TWO) too-heavy return springs, which SLOWS the rate of the timing advancement....which has the effect of limiting, or delaying, the advent of the distributor's (ever-) reaching its T.M.A. point....so that the engine will not 'ping', by not reaching the 36-degree Detonation-Threshold.

Now, the THIRD situation where your engine will ping is at/during sustained 'high-speed' crusing mode, when the Vacuum Advance (finally-) kicks-in, increasing the timing advancement.

A functioning V.A. IS needed, because, at cruise-mode, the engine is puttering-along at a relatively slow RPM, which means that the PISTONS are moving relatively slowly....compared to W.O.T.

The V.A. allows the sparking to occur with the piston being farther-down in the cylinder, in order to burn the fuel mixture as completely as possible.

The total-DEPTH (advancement) of the piston is important, because if the piston is too low/deep in the c.c., pinging WILL occur (similarly to that of the I.A. being set too deep, above).

VERY little is understood about the importance and the rating of the V.A. units.

On our cars, the V.A.'s advancement is indicated by a SMALL number that is stamped onto their lever-arms.

As the engine turns twice as fast as the distributor shaft, you need to multiply that small-number by "2" in order to convert to that number to the amount of the engine-degrees of advancement...which you are trying to determine.

On our cars (for the 4-bbl models), the danger-point is reached at about 50 degrees of Total Advancement ("T.A.") : I.A + M.A. + V. A.

UN-fortunately, it is very difficult to obtain either of the two versions of the "ideal" V. A..

You are looking for either a "7"(14) or a "8"(16) stamped onto the V.A.'s lever arm (OR, to have your dissie-doctor dial-in these advancements into your/another V.A.), in order to achieve 14-16 degrees of V.A.

In MY car, with its re-curved IAZ 4001E dissie, I have dialed-in 6 degrees of I.A. + 27 degrees of M.A. [that amount was confirmed by my own dissie-doctor, on his Sun-Analyzer] = 35 degrees of T.M.A. + 14 degrees of V.A. = 49 degrees of T.A. ......along with one (additional) light-weight return spring, to ensure a rapid advancement rate.

YES, Rolland, everything works together in our cars....

A hotter camshaft will open and close the valves quicker, but the distributor is the BRAINS of an engine, and the hot-cam will not work as efficiently as it could, if the IGNITION of the fuel is not compatible with the valves' operation.

Again (finally???), a 2-bbl carb can NOT supply as much fuel to the c.c. as can a 4-bbl carb; to take advantage of that limited mixture volume, and LOWER internal-PRESSURE, the factory allowed the 2-bbl dissie's advancement to be increased, to occur with the piston further down into the c.c., to try to burn the fuel as efficiently as possible,and with the T.A. being set at well ABOVE 50 degrees of T.A.

BUT, the 2-bbl dissies have very stiff return springs in them, so that their maximum T.A. might not be reached until RPM might exceed 4500RPM, or so.


AND, the reason that we-all want our car's dissies to approximate the 8+ 28+14 advancements, along with having light-weight return springing in them, is to allow the engines to operate at their maximum efficiency (both for MPG and MPH), without having or causing Detonation to occur.








Edited by d500neil 2014-08-31 3:29 AM
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d500neil
Posted 2014-08-30 7:54 PM (#454753 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



Exner Expert 19,174 posts. Neil passed away 18 Sep 2015. You will be missed, Neil!

Posts: 19146
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Location: bishop, ca


And now, for John's benefit, in Re: my knowledge about dissies, that I'm sharing with you all: my mentor has been Dave Homstad, of Rosemount, MN.

His professional background and resume is (John) :

"I got started on this project because I initially used the 1956 315 Poly 2 bbl distributor from my old engine in my rebuilt 1956 315 Hemi D500 engine, because it was working good when the new Hemi went in and I hadn't gotten to rebuilding the original D500 distributor. When I got the freshened D500 distributor ready, I was excited to see how much more power I would get with the correct high performance distributor. Then I put it in. What a let down!! Felt like I lost 50 hp. Then I looked up the specs and discovered the D500 had a ultra slow advance rate and very limited total mechanical advance. I suspect Mopar was concerned about the available fuel octane in their high compression engine (9.25 in 1956 Hemi vs. 8.0 in the Poly)."

My engineering background: BS degree in Physics, 40 years as a Quality Engineer in Aerospace, 45 years fixing/restoring my own cars, and a little drag racing.

Dave's website is :

http://webpages.charter.net/dhomstad/Distributor%20Frame1Source1.ht...

He welcomes contact/feedback.


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58coupe
Posted 2014-08-31 8:51 AM (#454810 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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Remember Neil, I started this conversation not to argue with you but to clarify what you are saying. You are mostly correct but ,again most of us already know that too much advance can cause pinging. This thread started with "2bbl. to 4bbl. swap" and I still maintain that you can do this without doing any damage to an engine. If you think of an engine as an air pump, (which it is) anything you do to allow it to pump more air makes more power. Letting an engine breathe better via a 4bbl. will improve its ability to make more power without hurting it if it is in good condition, but if you start playing with the timing advance and get too much too early you can definitely hurt it. You are always trying to encourage people to play with their dist. advance for "maximum performance" and this can get some people in trouble and do damage if not done right. I think we have beat this horse to death.
I hate to brag about myself but since you started it, I have almost 50 years as an automotive, truck and heavy duty, and licensed aircraft mechanic/inspector, so my experience is "hands on" not hypothetical. Forgot to mention commercial airline pilot (retired) but that does not apply much to this thread.
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Ray
Posted 2014-08-31 12:21 PM (#454820 - in reply to #454748)
Subject: Re: 2bbl to 4bbl swap


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d550neil

Thanks for the great information and link. No one can have too much information as long as s/he takes the time to understand it and use it correctly. 

 

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57chizler
Posted 2014-08-31 3:43 PM (#454829 - in reply to #454810)
Subject: Re: 2bbl to 4bbl swap



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58coupe - 2014-08-31 5:51 AM
This thread started with "2bbl. to 4bbl. swap" and I still maintain that you can do this without doing any damage to an engine.


And you are absolutely correct, sir. Anecdotal experience trumps theory every time.
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60 dart
Posted 2014-08-31 6:23 PM (#454838 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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been doin it for almost 50 yrs. . never even thought of it as a problem , because it never was . don't think i'll be worryin about it now ----------------------------------------------later
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fenix
Posted 2014-08-31 7:33 PM (#454839 - in reply to #454838)
Subject: Re: 2bbl to 4bbl swap



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60 dart - 2014-08-31 6:23 PM

been doin it for almost 50 yrs. . never even thought of it as a problem , because it never was . don't think i'll be worryin about it now ----------------------------------------------later


I don't know Chuck, I wouldn't be to quick to dispell this 2 to 4 bbl timing advance thing, I'm sure that poly stroker was a 2 bbl before ya put that Why-And intake and 4 bbl on it, and You do have an inexplainable water leak that is causing You some problems, maybe there is something going on here that we should reconsider. I for one am pulling my P-600 and 3 carbs off till I find out how exactly my VacA/MechA is set up, I would hate to blow up a new motor because i took the timing advance differences between a 2/4/6 bbl forgranted, heck with a 3X2, it may not even crank.

Edited by fenix 2014-08-31 7:35 PM
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58coupe
Posted 2014-08-31 9:35 PM (#454854 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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When they started racing the 426 hemi on fuel they kept advancing the timing and it kept making more power until it had 60 degrees of advance!!! more is better, right?
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fenix
Posted 2014-08-31 9:45 PM (#454858 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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And when they built the Poly stroker, it like less advance, thnk it's got a lot to do with the combo, effiency/VE, the total package.
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60 dart
Posted 2014-09-01 1:44 AM (#454870 - in reply to #454858)
Subject: Re: 2bbl to 4bbl swap



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actually it wasn't . it was a motor i bought yrs ago in maryland from a 60 phoenix . still have the original 4bbl , intake , single point dist , starter and gen.. now the dist. on the motor right now is a self contained
electronic unit , with advance ! the heads are the only parts off to old 2bbl motor . but it doesn't really matter . the problems i've stated on my stroker thread has absolutely nothing to do with this thread ---------------later
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60 dart
Posted 2014-09-01 2:57 AM (#454874 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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60 dodge parts manual is quite interesting . in a nut shell " all 1960 dodge PD4-318 dist's , except non-power pack , chrysler built 318 dist's , used the same vac. adv. , with no differences when using
an automatic or standard trans ,,,, part # 1881752 and that includes PD4-318 power pack . now if you want to doubt me , go look it up for yourself ----------------------------------------later
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fenix
Posted 2014-09-01 11:09 AM (#454894 - in reply to #454839)
Subject: Re: 2bbl to 4bbl swap



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fenix - 2014-08-31 7:33 PM

60 dart - 2014-08-31 6:23 PM

been doin it for almost 50 yrs. . never even thought of it as a problem , because it never was . don't think i'll be worryin about it now ----------------------------------------------later


I don't know Chuck, I wouldn't be to quick to dispell this 2 to 4 bbl timing advance thing, I'm sure that poly stroker was a 2 bbl before ya put that Why-And intake and 4 bbl on it, and You do have an inexplainable water leak that is causing You some problems, maybe there is something going on here that we should reconsider. I for one am pulling my P-600 and 3 carbs off till I find out how exactly my VacA/MechA is set up, I would hate to blow up a new motor because i took the timing advance differences between a 2/4/6 bbl forgranted, heck with a 3X2, it may not even crank.


My attempt to not make things worse.

 

First of all, My apologies Chuck, My post was a feeble attempt at humor in regards to what i would consider an absurd assumption that I would hesitate to run larger or even multiple carburation on a street driven gasoline burning V8 because of a minute change in a V8's timing advance in a 60's era distributor. And that doing so would wreck havoc on any and all related and unrelated syestems and dare i say sub-systems of said automobile as well.

Secondly, several of the members here and I have analyzed all of Your recent posts here and have determined You may in fact be suffering from TLSS ( temporary leaky stroker syndrome), while certainly not fatal, it does cause some pain and pressure on the right hip, usually where the temporary monetary holding container is stored, commonly referred to as a wallet, disrupted sleep patterns, some other syptomatic indicators such as wandering to the garage late at night and staring at the stroker motor, fiddling with objects that may have come in contact with the stroker but absolutely have no bearing as to why the motor leaks, and lastly and  importantly, but most understandably, temporary loss of the sense of the obvious, coupled with temporary loss of the sense of humor, even when such humor is only directed at you to distract and ease the pain of reality for a short period of time and the recovery starts.



Edited by fenix 2014-09-01 5:39 PM
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58coupe
Posted 2014-09-01 5:24 PM (#454923 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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Chuck, I have also been following your engine build and if you are using the original, matching cyl. heads, intake and front cover, it possibly is a gasket or maybe a crack that was missed. Let's hope it is only a gasket. BTW, the old hot rodders trick for valve clearance was to weld a small blade shaped piece of steel to a pair of old valves and install in the head for each cyl. and spin with a drill. It was tedious but if done slowly and carefully, effective.
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ttotired
Posted 2014-09-01 5:49 PM (#454926 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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Cool idea, turn an old valve into a milling tool

funny how this thread got railroaded

Normally its something thats so off subject like how the bronko's are going to go, or something like that, not a crossover to another active thread



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58coupe
Posted 2014-09-01 9:15 PM (#454935 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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It must be end of summer boredom!! I hope you are not mad at me Neil.
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dodge59
Posted 2014-09-05 9:45 AM (#455297 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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neil :
do you know if 1954 dodge indy pacecar with the 241 hemi offenhauser intake and wcfb carb added had the dual point distributor tweeked for the additional power increases. ? factory says they just added the intake and carb and no mention of a modified didtributor. mine has a IaZ 4003A like all 54 241 hemis .
Thanks !
john
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dodge59
Posted 2014-12-31 6:57 PM (#466349 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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I don't think mopar was in to performance in 1954 . in 55 or 56 they went nascar though with the dodge hemis
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60 dart
Posted 2014-12-31 8:02 PM (#466354 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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Chrysler Imperial
This 384 cubic-inch straight-eight with nine-main bearings, Winfield Model S carburetors, and magneto ignition was driven by Raul Riganti to a 14th place finish in the 1933 Indianapolis “500” . i know for sure
ma mopar was into performance in the 30's . their straight 8 was a big deal , always trying to stay ahead of the other straight 8's . in 54 ma got into the v-8 race , just not for dodge . then came 1955 and the
V-8 race was even bigger -----------------------------------------------------later
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Beltran
Posted 2015-01-01 11:59 AM (#466407 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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I don't think Chuck saw your post Fenix. Or he laughed finally and moved on. :D
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60 dart
Posted 2015-01-01 11:52 PM (#466441 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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huhhhhhhhhh , hell , that was months ago . i got 2 more gray hairs since then -------------------------------------------------------later
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ttotired
Posted 2015-01-02 7:30 AM (#466459 - in reply to #452840)
Subject: Re: 2bbl to 4bbl swap



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At least you GOT 2 MORE grey hairs Chuck

Mine are leaving

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