David Vizard, Uncle Tony's garage, Unity motorsport. Mission impossible Dodge 302 Head porting

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Cudafever said:
Hmmmm welll
When you recharge the AC on your car......the first step is to put it into a vacuum, to boil out the moisture. :poke: :lol:
Being a smart arss of course.......but there may be some merit to that.
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Hmmmm.....Wonder why the Ford guys fill in their ports. :poke:


Rat Bastid said:
If you use a Holley you have more choices to affect atomization and vaporization than any other carb.
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If that was the case Bruce wouldn't have had to build his carb to get the atomization and vaporization he wanted. When I asked Bruce about improving the design of the Holley carb his reply was "Why bother, by the time you fix it you might as well start with a Carter. His argument was for design not brand. He wasn't talking about AFB's

Greg said this:

See its like this.You don’t use cfm for optium power with a Holley carb,but its generally more that you need the cfm for poor performing engines.Its all about the burn,you need to realise that.Its not the afr,but rather the way that the cylinder burns the fuel that the carb puts in.The worse the efficiency of the burn,the more you have to use more cfm if the carby isn’t calibrated correctly.You will have to increase the cfm to obtain volumetric efficiency and then use the heat from the overlap period of the cam together with the opoorly calibrated carby so that the cylinders don’t detonate.If the exhaust is restrictive,then a poorly calibrated carb can work ok,you see this in many forms of motorsport.These engines make all their vaporisation in the compression stroke.This style of engine doenst make power with a well calibrated carb and high manifold vacuum.You have to treat these engines like individual runner designs.If an engine gets a very good burn then you can use 1.2 cfm to get 1 hp. As the efficiency of the burn drops you fall back to using 1.5-1.7 cfm per hp.
So you see there are many ways to run engines but there is only a few ways to have efficient ones.
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And this in the Shrinker thread.

we all have to deal with engines that make quite a bit of CO.we tune with holleys etc..
We dont have the luxury of very good droplet control so CO is there and a big part of it is good because its a colder burn.its a safer burn.
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Lots to think about in those 2 paragraphs......
 
Looks like he still managed 220 cfm with the quicky port.
 
Hysteric said:
Hmmmm.....Wonder why the Ford guys fill in their ports. :poke:




If that was the case Bruce wouldn't have had to build his carb to get the atomization and vaporization he wanted. When I asked Bruce about improving the design of the Holley carb his reply was "Why bother, by the time you fix it you might as well start with a Carter. His argument was for design not brand. He wasn't talking about AFB's

Greg said this:



And this in the Shrinker thread.



Lots to think about in those 2 paragraphs......
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Ok, remind me who Greg is.

I don’t know what Carter Shrinker would copy or why. And I’d love to get my hands on one of Bruce’s carbs.
 
Hysteric said:
Hmmmm.....Wonder why the Ford guys fill in their ports. :poke:




If that was the case Bruce wouldn't have had to build his carb to get the atomization and vaporization he wanted. When I asked Bruce about improving the design of the Holley carb his reply was "Why bother, by the time you fix it you might as well start with a Carter. His argument was for design not brand. He wasn't talking about AFB's

Greg said this:



And this in the Shrinker thread.



Lots to think about in those 2 paragraphs......
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Can you post links to those 2 threads?
 
Rat Bastid said:
Ok, remind me who Greg is.
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Greg is the guy Shrinker trained and worked with.

Rat Bastid said:
I don’t know what Carter Shrinker would copy or why. And I’d love to get my hands on one of Bruce’s carbs.
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It was the TQ. The whys will take a while to figure out because its design. Then the question becomes why does design matter and what does it influence.
 
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PRH said:
Not picking on Charlie at all, but he made a comment in what I think is the latest video....... where he’s talking about the 24hrs of R&D, and how the next port got a quickie job and flowed almost as much.
The comment being....... sometimes you need to know when to stop.

I’m thinking that would have been at about hour #2 or 3 on the first port.

My feeling on the head flow situation is.......as it pertains to this particular build is....... if the heads flowed 210-215, that would be plenty........ and still way more than the intake will keep up with.
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Well, if you have little experience with a port, which I'm pretty sure he said he had, and then your in a competition with someone else on modifying that port, then I guess you're going to put in a lot of time to see what can and can't be done.
Not to mention he may be looking to pick up some porting work from this, so the learning time plus the online exposure is an investment.
 
Hysteric said:
Hmmmm.....Wonder why the Ford guys fill in their ports. :poke:




one of the biggest reasons to fill a port is the port is to big for most applications. For a quick example let’s take the 351 Cleveland and 426 Hemi for an example. Have you ever seen a stock one that could hold it’s on on the street. I ate them for lunch back in the 1970’s and 1980’s on the street and strip. Now if the would know the proper place to slightly fill those ports with epoxy you could probably run much better.
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Now if the would know the proper place to slightly fill those ports with epoxy you could probably run much better.
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Totally agree. One day when I get around to it I'm gonna take the 587's I have and machine the chambers right down till I get a a nice big fat quench area and fill that horrible divot in the floor till I get the same cfm but with a much smaller port volume and stick it on a 318 and see how it performs.
 
One day, when I get around to it, I'm going to sell all my cars, most of my tools, and finish my P51 Mustang.
 
Bakerlite said:
Well, if you have little experience with a port, which I'm pretty sure he said he had, and then your in a competition with someone else on modifying that port, then I guess you're going to put in a lot of time to see what can and can't be done.
Not to mention he may be looking to pick up some porting work from this, so the learning time plus the online exposure is an investment.
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My view on something like a SBM head is that it’s just not that much different than the stuff he’s often working on.
When it didn’t show a noticeable improvement after about the 4th of 5th time on the bench, I’d have taken that as a sign, along with my previous years of messing with that stuff(like he has), and know it’s time to stop.

But, he was a good choice for that job.
I’ve seen him spend countless hours messing with “science experiment” heads in the past.

The 24hrs he has messing around with R&D on that one intake & exhaust port is more time than I’d spend on the complete porting job.
 
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Hysteric said:
Totally agree. One day when I get around to it I'm gonna take the 587's I have and machine the chambers right down till I get a a nice big fat quench area and fill that horrible divot in the floor till I get the same cfm but with a much smaller port volume and stick it on a 318 and see how it performs.
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You wouldn’t be the first person to try raising the port till you break through the spring pocket. Lots of JB welded in spring locators on stock type limited area heads. Go north my son. Lol
 
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Jadaharabi said:
I think this is the latest vidio.

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I've pretty much stayed out of the hypo-hippo-hypothermo- of this thread... you get the idea. However, that is a lot of work to get around 220 at .450. A lot of work, and as he mentioned, a lot of material had already been taken out. I understand their project and why they are doing it, but in no wise is this head the recommended head for anyone looking for flow at .450-.500 lift of them flow numbers. For all practical purposes, this is about the most expensive way to get there. But this build is for fun. Let them continue ... :)
 
I think the speedmaster (unported OOTB) flow 221 @ only .400 lift?? I gave 699 for a pair fully loaded to the front door. Again, I know they are doing this just for the sake of doing it, and I like the project. "because we can, not because you should" kinda sorta
 
Hysteric said:
Totally agree. One day when I get around to it I'm gonna take the 587's I have and machine the chambers right down till I get a a nice big fat quench area and fill that horrible divot in the floor till I get the same cfm but with a much smaller port volume and stick it on a 318 and see how it performs.
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BTDT. It will lose power and if you run much compression it will be almost impossible to keep the head gaskets happy.
 
318willrun said:
I think the speedmaster (unported OOTB) flow 221 @ only .400 lift?? I gave 699 for a pair fully loaded to the front door. Again, I know they are doing this just for the sake of doing it, and I like the project. "because we can, not because you should" kinda sorta
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And that OOTB SM head will blow the doors off that 302 all day long even taking Sunday off.
 
Hysteric said:
Totally agree. One day when I get around to it I'm gonna take the 587's I have and machine the chambers right down till I get a a nice big fat quench area and fill that horrible divot in the floor till I get the same cfm but with a much smaller port volume and stick it on a 318 and see how it performs.
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I went down that rabbit hole once.

DSCN2011.jpg


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never finished it.
Got one intake port to to 285 cfm and a 170 cc port. could not duplicate it in any other port. still have 2 intake ports that have not been done.
someday i will pull them back out and dust them off...........hoping i have learned enough about this stuff to see what was different about that port.
I made templates out of solider and Z-spar, of that port, to copy to the matching ports. but never got the same resorts. was the only port with epoxy in it that would flow to 0.600 lift with out crashing.
IMG_2139.jpg

IMG_2140.jpg
I dug it out sever times, and re did it with epoxy and with a little clean up it would come back, but never on any other port.
I truly believe its in the valve job and combustion chamber. but haven't looked back on them heads in years.
 
PRH said:
My view on something like a SBM head is that it’s just not that much different than the stuff he’s often working on.
When it didn’t show a noticeable improvement after about the 4th of 5th time on the bench, I’d have taken that as a sign, along with my previous years of messing with that stuff(like he has), and know it’s time to stop.

But, he was a good choice for that job.
I’ve seen him spend countless hours messing with “science experiment” heads in the past.

The 24hrs he has messing around with R&D on that one intake & exhaust port is more time than I’d spend on the complete porting job.
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I'm guilty of sometimes spending a lot of time trying things out.. I actually quite enjoy that part of this hobby.
 
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