uncle tony's garage gets called out by the roadkill guys

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67Dart273

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and they say he's full of ****
Kahill Smith replied.................
I just opened up my Mopar Engine Carroll Shelby's Speed Secrets book from Direct Connection and it states on page 44, section E for Pistons and Pins , the 3rd paragraph that "Factory pistons have the pin offset to reduce piston slap. By reversing the offset (reversing the piston) engine friction can be reduced. In engines equipped with power pak (domed) pistons this can be accomplished by installing pistons from the right bank in the left bank and vise versa. This means the notch in the edge of the piston top will now be toward the rear of the engine. With two barrel flat top pistons , it is only necessary to reverse the piston pin on the rod and not necessarily to swap from bank to bank. A piston to bore clearance of .0015 - .002 has proven to be adequate with stock type pistons. Race pistons do not have a piston offset and there-fore don't need to be reversed. " That was a lot of typing for me.

 
I wonder how much of this stuff is staged to increase controversy and to get attention.
Who uses stock pistons anyway?
Many of these engines are 50 years old or more. To use the heavy stock pistons when lighter and stronger ones are available is stupid.
I like UTG as well as Dulcich and FB. Dulcich does sound sort of stupid when he calls FB by the last name. When you’re friends with someone, do you really use their last name? This isn’t team sports or the military.
 
I bought a set of Keith Black Pistons back in 2008, i am sure they cost much more now,and I forget what I paid then...:)

I remember overhauling my 318 back in 2003 for around $500,now who knows I'm sure you'd get over a grand...I think in that $500 was an Edelbrock intake brand new.
 
A new set of racing pistons will cost you about $600.00 bucks now a days. I wanted to use the original pistons in my 340 build but it needed to be bored 0.030 over. So I ended up with a set of JE pistons and Scat I-beam rods. My machinist had to remove significant material from the crankshaft during the balancing process. 65'
 
Just a clown with a cigarette in his hand and an opinion.
 
I wonder how much of this stuff is staged to increase controversy and to get attention.
Who uses stock pistons anyway?
Many of these engines are 50 years old or more. To use the heavy stock pistons when lighter and stronger ones are available is stupid.
I like UTG as well as Dulcich and FB. Dulcich does sound sort of stupid when he calls FB by the last name. When you’re friends with someone, do you really use their last name? This isn’t team sports or the military.

FB has been called that the whole time. Even on the original Roadkill, by Mike Finnegan. FB also called him by his last name. Just my .02
 
I knew a guy who was rebuilding a 2nd gen 426 HEMI, and reversed the pistons, unintentionally, and it didn't work AT ALL, hahaha.
In other words, it bent some valves, first time he tried rotating the crank.
 
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FB has been called that the whole time. Even on the original Roadkill, by Mike Finnegan. FB also called him by his last name. Just my .02
Finnegan sounded fine saying it. Steve Dulcich sounds...uhhh...mentally compromised when he says it. I like the guy but he sounds like a guy that loves his Scooby Doo lunchbox and gives strangers great big hugs.
 
O.K. Here we go. I will explain this to you guys. It has nothing to do with piston slap. Maybe a little but it is not what makes more power.

When your crankshaft and your con rod is at 90 degrees the piston is 1/2 way down the bore. Or close to it. Actually not more like 1/4 way down, got a little carried away there.

Now the wrist pin is offset to the left looking at the front of the motor. You with me. O.K.

Now in your imagination move the wrist pin to the right about .100" That is about the offset of the pin.

The rod is now closer to vertical, so it is now taller and the piston is higher in the bore, now the crankshaft has not moved it is still in the same place.

Now you have to rotate the crank clockwise further to get the rod and the crank at 90 degrees.

So by swapping them left to right the piston is higher in the bore when the crank and rod are at 90 degrees, that is where you have the max push on the crank, as is the longer the arm.

Here are some 340 pistons you can clearly see the offsetView attachment 1715750107 View attachment 1715750107

Now to the swap, All you have to do is swap them. Think about it when you take a piston and rod assy out of the left bank and rotate it 180* the rod is in the correct position for the right bank.

Hope this helps.

IMG_6926.JPG


IMG_6916.JPG


IMG_6924.JPG


Sorry about the pictures, I thought i had them right but then screwed them up LOL

I think you can figure them out.
 
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..............
and they say he's full of ****
Kahill Smith replied.................
I just opened up my Mopar Engine Carroll Shelby's Speed Secrets book from Direct Connection and it states on page 44, section E for Pistons and Pins , the 3rd paragraph that "Factory pistons have the pin offset to reduce piston slap. By reversing the offset (reversing the piston) engine friction can be reduced. In engines equipped with power pak (domed) pistons this can be accomplished by installing pistons from the right bank in the left bank and vise versa. This means the notch in the edge of the piston top will now be toward the rear of the engine. With two barrel flat top pistons , it is only necessary to reverse the piston pin on the rod and not necessarily to swap from bank to bank. A piston to bore clearance of .0015 - .002 has proven to be adequate with stock type pistons. Race pistons do not have a piston offset and there-fore don't need to be reversed. " That was a lot of typing for me.


We know this.
Tony doesn't.
Any stock replace. Sealed power includ hyper stock replace,badger,silvolite,mahl, etc has offset...performance piston designs utilized that knowledge.
 
I wonder how much of this stuff is staged to increase controversy and to get attention.
Who uses stock pistons anyway?
Many of these engines are 50 years old or more. To use the heavy stock pistons when lighter and stronger ones are available is stupid.
I like UTG as well as Dulcich and FB. Dulcich does sound sort of stupid when he calls FB by the last name. When you’re friends with someone, do you really use their last name? This isn’t team sports or the military.
Or the boy scouts.

That's an old school thing, the last name.
 
IF you build engines out of the scrap pile, and IF your machinist tools are a carpenters level and a flashlight, and your goal is to gain maybe 5 horsepower, it MIGHT be worth trying. Otherwise, complete waste of time
 
IF you build engines out of the scrap pile, and IF your machinist tools are a carpenters level and a flashlight, and your goal is to gain maybe 5 horsepower, it MIGHT be worth trying. Otherwise, complete waste of time


I seriously doubt there is 5 horsepower in flipping the pistons. It’s just not there.
 
..............
and they say he's full of ****
Kahill Smith replied.................
I just opened up my Mopar Engine Carroll Shelby's Speed Secrets book from Direct Connection and it states on page 44, section E for Pistons and Pins , the 3rd paragraph that "Factory pistons have the pin offset to reduce piston slap. By reversing the offset (reversing the piston) engine friction can be reduced. In engines equipped with power pak (domed) pistons this can be accomplished by installing pistons from the right bank in the left bank and vise versa. This means the notch in the edge of the piston top will now be toward the rear of the engine. With two barrel flat top pistons , it is only necessary to reverse the piston pin on the rod and not necessarily to swap from bank to bank. A piston to bore clearance of .0015 - .002 has proven to be adequate with stock type pistons. Race pistons do not have a piston offset and there-fore don't need to be reversed. " That was a lot of typing for me.




I watched that. Dulcich needs a hair cut and Freiberger needs some damn shoes. One can also tell that DF isn’t a machinist. You can do the test with an aftermarket piston on a fresh engine. Most every KB piston I’ve seen is machined for pin locks. You use a bushed rod (alike everyone SHOULD be using) and do the swap.

If some whiz bang in gym shorts wants to test this, I’ll donate 2 days of dyno time to test it. But I’m just running the stick. Someone else needs to spin the wrenches.
 
I watched that. Dulcich needs a hair cut and Freiberger needs some damn shoes. One can also tell that DF isn’t a machinist. You can do the test with an aftermarket piston on a fresh engine. Most every KB piston I’ve seen is machined for pin locks. You use a bushed rod (alike everyone SHOULD be using) and do the swap.

If some whiz bang in gym shorts wants to test this, I’ll donate 2 days of dyno time to test it. But I’m just running the stick. Someone else needs to spin the wrenches.
Richard holdner is supposed to be testing this very thing soon
 
IF you build engines out of the scrap pile, and IF your machinist tools are a carpenters level and a flashlight, and your goal is to gain maybe 5 horsepower, it MIGHT be worth trying. Otherwise, complete waste of time

Agree , doubt its worth 5 h.p. tho !~
 
I guess back in the day when nobody had any money it was worth doing.
 
Yeah...”great” idea.
Take apart an engine, spend the money on gaskets to achieve a gain that nobody can feel.
 
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