Haha.
Well, uhhhh. You know, there is probably some truth to that - I work best under pressure so I get stuff done. It's a great excuse not to leave this awesome stroker engine laying around doing nothing...
HawkRod is doing the 2023 Hot Rod Power Tour!
- Thread starter HawkRod
- Start date
Well, uhhhh. You know, there is probably some truth to that - I work best under pressure so I get stuff done. It's a great excuse not to leave this awesome stroker engine laying around doing nothing...
Tick tock Hawk!
70bigblockdodge
Well-Known Member
I'm planning on going. I will not be building a engine. Just a nut and bolt check and a new driveshaft. Hope to see you there.
In other words, you are an intelligent guy who doesn't have crazy projects before big trips...
Me? I guess I'm a little crazy,
but it does help me get stuff done...
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In other words, you are an intelligent guy who doesn't have crazy projects before big trips...
Me? I guess I'm a little crazy,
easy is boring
64fury74charger
Well-Known Member
Hawk you are preparing for another fantastic trip with all
the detailed information and pictures and of course that deadline looming so close. Last years trip was absolutely fantastic and this one will be another great adventure. I am looking forward to following along with you. Thank you for your time and patience to post your pictures and updates with lots of valuable information.
the detailed information and pictures and of course that deadline looming so close. Last years trip was absolutely fantastic and this one will be another great adventure. I am looking forward to following along with you. Thank you for your time and patience to post your pictures and updates with lots of valuable information.
Well, I did some more checking of the block and also checked some pistons. Unfortunately the news for each was not great and is adding to the work I have to do.
For those who don't want all the details: I have to deck my block and cut weight off my pistons. (Keep reading below if you like details.)
I checked to see how "square" the block is. The crank centerline defines the heart of the block. You want the deck surface to be the exact same distance from the crank centerline for every cylinder. If is it very different, you end up with different compression in different cylinders so the engine does not run as well. If the value is the same for all 8 cylinders, the block is "square". Less than .002" difference is fine.
For those that haven't seen this done, here is one way to do it:
There is a 2.000" metal bar that goes through your mains. To make the bar fit your mains, there are custom rings that are exactly 2.000" ID and the OD of your block mains. In this picture I am holding a ring for a 440 (the 383/400 rings on already in my block). One each goes in journal #1 and #5.
Then you take a "T" gauge and measure from the deck of the block on one side (in the picture below I am measuring cylinder #7) down to the metal bar inserted in the step above. In this case, I didn't care about the actual distance - I just set the gauge to read zero. (By the way, the actual length turned out to be 9.968", so this means my reference point was .012" below the factory spec of 9.980" - so this block had been decked before).
Then, without changing the gauge setup, I measured cylinder #1. It measured -.001", meaning is was .001" LESS distance to the bar than cylinder #7.
This is actually a good measurement - a .001" difference is good. But then I measured the other side of the block (cylinders 2 & 8). Cylinder 8 measured -.002", and then cylinder 2 measured -.003".
So back to front both sides of my block differ in length by .001", but the even side cylinders bank is .002" less than the odd side. Not a killer, but not great either.
But then the surface finish tipped the scales. The block surface finish is quite rough. If you scrape your fingernails against the surface of the deck you can feel the ridges. This is not great for sealing. Today's technology (head gaskets) like the surface to be more smooth.
Per se, none of these things are killers, but they are not great collectively - at least not as close as I'd like them. So to clean up the ridges and square up the block, I will deck the block about .005" below my reference point. (That means I will shave off .005" at cylinder #7 and .002" at cylinder #2.)
Bottom line is after decking the block will be smooth and square, but I was hoping not to have to spend the time to do this.
But the big surprise was my pistons. This engine had high end KB (now Icon) forged pistons. I had a few minutes and decided to weigh them to finish getting them ready for later assembly. Weighing each is simple - just plunk it on the scale:
You want each one to be within a half gram of one another. Piston 1 is shown above at 503.5 grams. Great, then #2, #3, etc.
I was feeling really good until I got to piston #6. WTF?!?! It is 4.5 grams light!
I expected better from these pistons, and I am disappointed in the large difference. Also, I would be happier if one or two pistons were heavy, then I might have to work on one or two pistons. But now I need to modify 7 pistons to decrease their weight so ALL weigh 499 grams.
CRAP!
Also, these are small and light already, so it won't be easy grinding out 4 grams or so out of each. So how do you do that?
Well, There are little tabs on the insides of the pistons. This is a key area where you can take some material out without sacrificing the strength of the pistons. There are 4 little tabs that can be ground on each piston. In the picture below I colored black in the approximate material shape to remove.
I'll try to get this done next week, but the highest priority will be to deck the block.
For those who don't want all the details: I have to deck my block and cut weight off my pistons. (Keep reading below if you like details.)
I checked to see how "square" the block is. The crank centerline defines the heart of the block. You want the deck surface to be the exact same distance from the crank centerline for every cylinder. If is it very different, you end up with different compression in different cylinders so the engine does not run as well. If the value is the same for all 8 cylinders, the block is "square". Less than .002" difference is fine.
For those that haven't seen this done, here is one way to do it:
There is a 2.000" metal bar that goes through your mains. To make the bar fit your mains, there are custom rings that are exactly 2.000" ID and the OD of your block mains. In this picture I am holding a ring for a 440 (the 383/400 rings on already in my block). One each goes in journal #1 and #5.
Then you take a "T" gauge and measure from the deck of the block on one side (in the picture below I am measuring cylinder #7) down to the metal bar inserted in the step above. In this case, I didn't care about the actual distance - I just set the gauge to read zero. (By the way, the actual length turned out to be 9.968", so this means my reference point was .012" below the factory spec of 9.980" - so this block had been decked before).
Then, without changing the gauge setup, I measured cylinder #1. It measured -.001", meaning is was .001" LESS distance to the bar than cylinder #7.
This is actually a good measurement - a .001" difference is good. But then I measured the other side of the block (cylinders 2 & 8). Cylinder 8 measured -.002", and then cylinder 2 measured -.003".
So back to front both sides of my block differ in length by .001", but the even side cylinders bank is .002" less than the odd side. Not a killer, but not great either.
But then the surface finish tipped the scales. The block surface finish is quite rough. If you scrape your fingernails against the surface of the deck you can feel the ridges. This is not great for sealing. Today's technology (head gaskets) like the surface to be more smooth.
Per se, none of these things are killers, but they are not great collectively - at least not as close as I'd like them. So to clean up the ridges and square up the block, I will deck the block about .005" below my reference point. (That means I will shave off .005" at cylinder #7 and .002" at cylinder #2.)
Bottom line is after decking the block will be smooth and square, but I was hoping not to have to spend the time to do this.
But the big surprise was my pistons. This engine had high end KB (now Icon) forged pistons. I had a few minutes and decided to weigh them to finish getting them ready for later assembly. Weighing each is simple - just plunk it on the scale:
You want each one to be within a half gram of one another. Piston 1 is shown above at 503.5 grams. Great, then #2, #3, etc.
I was feeling really good until I got to piston #6. WTF?!?! It is 4.5 grams light!
I expected better from these pistons, and I am disappointed in the large difference. Also, I would be happier if one or two pistons were heavy, then I might have to work on one or two pistons. But now I need to modify 7 pistons to decrease their weight so ALL weigh 499 grams.
CRAP!
Also, these are small and light already, so it won't be easy grinding out 4 grams or so out of each. So how do you do that?
Well, There are little tabs on the insides of the pistons. This is a key area where you can take some material out without sacrificing the strength of the pistons. There are 4 little tabs that can be ground on each piston. In the picture below I colored black in the approximate material shape to remove.
I'll try to get this done next week, but the highest priority will be to deck the block.
Last edited:
64fury74charger
Well-Known Member
This is really good information with your explanation of how you got your measurements and exactly what those numbers mean to you. Careful and paying attention to the details really pays when your driving on a real road trip. Outstanding as always. Thank you for letting everyone follow along.
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Hot dang, Hawk is going on another adventure for us!
Sure, I'll be following as always...
Quick layman's question on the pistons - is it possible to just add weight to the one "light" one instead?
Ed, it is a great question.Hot dang, Hawk is going on another adventure for us!
Sure, I'll be following as always...
Quick layman's question on the pistons - is it possible to just add weight to the one "light" one instead?
I am no engine building master, and don't claim to be. I am still an apprentice to my father-in-law, and continue to learn stuff. I have balanced probably 10 sets of pistons so far, and have always simply removed weight. Could weight be added? I'm sure in theory it could, but I'd think the weight would need to be added by welding the correct aluminum alloy. But what would welding on a perfectly formed and sized piston do? Might it get warped or have some other issue? When the piston is reciprocating at 6000 RPM will the added weight cause problems or come loose?
Bottom line is I have never heard of anyone adding weight to a piston. I don't doubt it has been done, but from my limited experience it would have to be a very special case indeed to try and do that.
70bigblockdodge
Well-Known Member
Yeah, I'm not sure I would call me intelligent. Your talking about a guy who pieced together a '68 Charger with little to no new parts. First ride was on Tuesday up the street about a block and back. Wednesday went a little further about a mile and a half then back. Thursday off to the Mopar Nats.In other words, you are an intelligent guy who doesn't have crazy projects before big trips...
Me? I guess I'm a little crazy,
Used a sure grip with cracked case at pin, welded the case and pin to remove slop from crack, it is not serviceable at this point, on its final ride to the end. Block is a 1966, crank and 7 rods and Pistons are from a 1970 engine, one piston (number 5) is a eighties aftermarket .030 piston (sanded down to fit a standard bore)with a 1973 rod. Trans is a 833, 4 spd overdrive from a pick up truck that was locked up when I got it, front bearing had rusted, swapped an go to go. Wears a thermoquad on top that is the " good parts" from 3 different Thermoquad. Driveshaft and rear shocks are from a 1974 Fury. Driveshaft shortened by me and shocks because they looked new except they sat for 30 years, when they leak I'll change them.
This whole mess has now covered 13.5k miles over the last 5 years, it is a absolute blast to drive knocks down ~ 15.5 mpg. Drove it down (and back) to Charleston, South Carolina last June. I try to improve something every year over winter, but have no intention of ever making it so nice I will have to worry about a fly shitting on it. It will be my son's car when I pass, and I hope he enjoys it as much as he and I have so far.
Sorry for the highjack, it got long winded. Look for this junk on power tour.
Yes, before you ask I'm trying different shades of orange to see which one I like.
So it's a pretty good bet that your pistons aren't within 4 grams of each other?
70bigblockdodge
Well-Known Member
well 7 of them maybe. Number 5?
Close your eyes and you can pretend they are.
That motor did clean up the shop pretty good.
What an awesome story and car. It is a bit like my "RoadKill Runner" that I drove across country - just that your car is cooler!
Not only will I look for your car on the tour, we should try to hook up for a cup of coffee or a cold adult beverage - us PA guys need to stick together!
P.S. I like the quarter panel orange best.
P.S.S. For the record, I have experimented with some different shades of yellow on the 73 Road Runner.
Haha. Great point Don.
Mopar engines are actually known to be pretty variable with respect to machining, especially how square they are from the factory. I heard this had to do with the jig that held the blocks when they were decked, bored, etc. Metal shavings would end up on the jig and the blocks would then rest on some metal shavings and not be cut straight. It made some of the engines run like scared apes when they were built right, and others, well, not so much.
To your point, I really don't HAVE to do some of the stuff I'm doing to my engine - but with access to a full machine shop, why not blueprint the engine when you can?
70bigblockdodge
Well-Known Member
YesNot only will I look for your car on the tour, we should try to hook up for a cup of coffee or a cold adult beverage - us PA guys need to stick together!
I have a 400-2 bbl came out of a scrap 74 fury. It is the most square engine I have messed with, at least to the crude measuring I use. The crank keyway was even cut dead on, I think it is the only BB I have ever had be TDC accurate. I just figured it was a Wednesday am engine. The jig story makes sense
So I decked my block and got is set up for honing.
To deck the block, I first had to remove the alignment pins. This tool goes on the pin
Then it tightens around the pin. Turning the nut on the black collar pulls it out.
To set the block up for decking, your two reference points are the crank line and the cam line. This plate gets attached between the two and it is held in the machine.
You then align the block side to side using the metal plate with the gauge on the actual cutting head. The gauge reads to .0005", but I try to get it within half a line, or about .0002". The deck might not have been cut square - this assures your cut will be square and correct. You can't use the actual deck of the block because that might not have been cut right.
After this, you can check the block itself and see how it measures up (no pictures of this). This block was really pretty nice. My father-in-law says many of the Mopar blocks in the day were off by .016" or even more. This one was off by .003", and really didn't HAVE to be done. But I have the machine, so why not try to improve it? (Plus, I wanted a smoother surface).
To set up for the cut, I color part of the deck in black magic marker.
When the cutting wheel turns the black marker to gray, then you know you are at "zero" - anything more and you are now taking material off the block. In my case, I cut another .005"
Here is a picture as it is beginning the cut
And done! The cut takes about 2-3 minutes. The setup can take over an hour!
So, how did it turn out? Here is cylinder 8:
...and here is cylinder 1
The above is not a great picture, but it is off about .0005" front to back. Both sides are now also within .001". Nice and square with a smooth cut.
Ready for honing!
To deck the block, I first had to remove the alignment pins. This tool goes on the pin
Then it tightens around the pin. Turning the nut on the black collar pulls it out.
To set the block up for decking, your two reference points are the crank line and the cam line. This plate gets attached between the two and it is held in the machine.
You then align the block side to side using the metal plate with the gauge on the actual cutting head. The gauge reads to .0005", but I try to get it within half a line, or about .0002". The deck might not have been cut square - this assures your cut will be square and correct. You can't use the actual deck of the block because that might not have been cut right.
After this, you can check the block itself and see how it measures up (no pictures of this). This block was really pretty nice. My father-in-law says many of the Mopar blocks in the day were off by .016" or even more. This one was off by .003", and really didn't HAVE to be done. But I have the machine, so why not try to improve it? (Plus, I wanted a smoother surface).
To set up for the cut, I color part of the deck in black magic marker.
When the cutting wheel turns the black marker to gray, then you know you are at "zero" - anything more and you are now taking material off the block. In my case, I cut another .005"
Here is a picture as it is beginning the cut
And done! The cut takes about 2-3 minutes. The setup can take over an hour!
So, how did it turn out? Here is cylinder 8:
...and here is cylinder 1
The above is not a great picture, but it is off about .0005" front to back. Both sides are now also within .001". Nice and square with a smooth cut.
Ready for honing!
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64fury74charger
Well-Known Member
Thank you for your time to post pictures and clear explanations on what your doing and why. Awesome
I then set up my block for honing. We will take out only about .001" to tidy up the walls and give room for my coated pistons.
Here I am with my block about to be inserted into the honing machine.
Once in the machine, a torque plate is bolted on and properly torqued to the block. This mimics a head and provides the same metal distortion in the bores as the head creates. Then it is honed. When a head is bolted on for good, the bores should be perfectly round.
I haven't run the honing machine yet, and it takes some "touch", especially given that my block only needs about .001" honed out of it. So my father-in-law will do this - hopefully this week!
As an aside, next to the honing machine is my father-in-law's 409 that he runs in his 62 bubble top Bel Air. It runs low 10s in nostalgia trim (no turbos, nitrous, blower, original style carbs, etc.)
Like the Hemi, I think the 409 is a very distinctive engine.
Hopefully next week I can get to some other tasks and get this engine done soon!
Here I am with my block about to be inserted into the honing machine.
Once in the machine, a torque plate is bolted on and properly torqued to the block. This mimics a head and provides the same metal distortion in the bores as the head creates. Then it is honed. When a head is bolted on for good, the bores should be perfectly round.
I haven't run the honing machine yet, and it takes some "touch", especially given that my block only needs about .001" honed out of it. So my father-in-law will do this - hopefully this week!
As an aside, next to the honing machine is my father-in-law's 409 that he runs in his 62 bubble top Bel Air. It runs low 10s in nostalgia trim (no turbos, nitrous, blower, original style carbs, etc.)
Like the Hemi, I think the 409 is a very distinctive engine.
Hopefully next week I can get to some other tasks and get this engine done soon!
Last edited:
Hawk, did you take any pictures of the piston skirts before you had them coated? I'm dying to know how those short skirts held up.
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