400/450 stroker....Cheap parts, lotta work.

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IQ52

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Kinda got the 346 iron heads ready for the KB251 pistons. Flat chamber depths were from .084"-.102" and they are all now .110". The quench pad on the pistons are .260" tall and we'll have to mill about 1/2 that off or rather some .125" with the preliminary measurements.

Cody and I are having some fun with this engine. Just went and bought the 251's because they were the cheapest stroker piston I could buy. We'll be using rebuilt stock 6.358" 400 rods. They are of course just a teeny bit shorter now.

400-450 001.JPG
400-450 008.JPG
 
Kinda got the 346 iron heads ready for the KB251 pistons. Flat chamber depths were from .084"-.102" and they are all now .110". The quench pad on the pistons are .260" tall and we'll have to mill about 1/2 that off or rather some .125" with the preliminary measurements.

Cody and I are having some fun with this engine. Just went and bought the 251's because they were the cheapest stroker piston I could buy. We'll be using rebuilt stock 6.358" 400 rods. They are of course just a teeny bit shorter now.

View attachment 1715685393 View attachment 1715685394


WOW...that was a ton of work. Looks damn nice.
 
Wasn’t there a recent post where someone said something along the lines of, “Dad....... just no more iron”.
 
Wasn’t there a recent post where someone said something along the lines of, “Dad....... just no more iron”.
Way less pressure and more fun when you are doing it for yourself. We have three more besides this......just for us. A 440 for the Trail Duster hunting rig, and two 383's. One for the 4-wheel drive 1968 Chrysler Town and Country wagon and the other for the 833 4-spd '67 2-wheel drive Coronet wagon.
 
We're using the cheapo 400 6.358" factory rods. I didn't think to measure the rod lengths before the rebuild but they are now.....

#1) 6.355"
#2) 6.355"
#3) 6.357"
#4) 6.351" from a different engine
#5) 6.356"
#6) 6.356"
#7) 6.357"
#8) 6.355"

Probably move them around some and use #4 in the smallest combustion chamber. Lotta work, just like the cheapo 346 iron heads.............

400-450 rods 002.JPG


After we measure all the crankshaft throws and before the balancing, I'll cut the quench pads for each cylinder so there is zero piston to head clearance with no head gasket and then use the 8519PT1 head gasket for .039" clearance. Should be enough.
 
What will the final quench be? I did similar about 15 years back, but I had the recesses in the heads machined, didn't do it by hand.
 
What will the final quench be? I did similar about 15 years back, but I had the recesses in the heads machined, didn't do it by hand.

He told you. .039".
 
What will the final quench be? I did similar about 15 years back, but I had the recesses in the heads machined, didn't do it by hand.
Most work was done on a vertical mill with hand touch up.
 
After decking the block all four corners are 9.968"..............

400-450 004.JPG


This is the test rod of know length, 6.356". I had the press fit pin end honed so the pin will slip in/out and I can test the machined crank (standard 400 mains and .020" under rods) for stroke length on each throw. Any piston I want to use will just slip on and off.
400-450 test rod 001.JPG
 
... This is the test rod of know length, 6.356". I had the press fit pin end honed so the pin will slip in/out and I can test the machined crank (standard 400 mains and .020" under rods) for stroke length on each throw. Any piston I want to use will just slip on and off.

I have one of those plus others for different engines.
 
After decking the block all four corners are 9.968"..............

View attachment 1715685919

This is the test rod of know length, 6.356". I had the press fit pin end honed so the pin will slip in/out and I can test the machined crank (standard 400 mains and .020" under rods) for stroke length on each throw. Any piston I want to use will just slip on and off.
View attachment 1715685920

What are you going to do for the difference in rod lengths. I read it, but I'm so dumb I cannot comprendo. Can you stupid it up some?
 
I have four pistons @ 1.722" CH and four @ 1.723". Once I have checked all the rod throws for stroke length using my test rod and one piston, I can do a dance with rod length, CH, and stroke length to get all deck heights as close as possible. It won't make any difference on the stamped rod number as I may use it in a different cylinder number (i.e. #1 rod in place of #6). Then before the balancing is done I will machine each quench pad for a specific cylinder depending on the deck height. After the dance if #3 piston is .003" lower in the bore than #7, I will leave the quench pad .003" taller on #3 than the pad on #7 piston. I can do it this way because all the flats in the head combustion chamber are all .110" below the head face.

Even though the flats are all the same in the heads, the combustion chambers are a little different in cc's. Because rod #4 is so short I may shuffle it to a combustion chamber that is smaller in cc's than the others to attempt to balance the compression ratios from cylinder to cylinder.

Still clear as mud right?
 
I have four pistons @ 1.722" CH and four @ 1.723". Once I have checked all the rod throws for stroke length using my test rod and one piston, I can do a dance with rod length, CH, and stroke length to get all deck heights as close as possible. It won't make any difference on the stamped rod number as I may use it in a different cylinder number (i.e. #1 rod in place of #6). Then before the balancing is done I will machine each quench pad for a specific cylinder depending on the deck height. After the dance if #3 piston is .003" lower in the bore than #7, I will leave the quench pad .003" taller on #3 than the pad on #7 piston. I can do it this way because all the flats in the head combustion chamber are all .110" below the head face.

Even though the flats are all the same in the heads, the combustion chambers are a little different in cc's. Because rod #4 is so short I may shuffle it to a combustion chamber that is smaller in cc's than the others to attempt to balance the compression ratios from cylinder to cylinder.

Still clear as mud right?
if you didn't do any of that, and kept the rpm maxed at 5500 rpm, it wouldn't matter too much would it? It would affect longevity, and smooth operation, but the bearings wouldn't suffer immediately would they?
 
I have four pistons @ 1.722" CH and four @ 1.723". Once I have checked all the rod throws for stroke length using my test rod and one piston, I can do a dance with rod length, CH, and stroke length to get all deck heights as close as possible. It won't make any difference on the stamped rod number as I may use it in a different cylinder number (i.e. #1 rod in place of #6). Then before the balancing is done I will machine each quench pad for a specific cylinder depending on the deck height. After the dance if #3 piston is .003" lower in the bore than #7, I will leave the quench pad .003" taller on #3 than the pad on #7 piston. I can do it this way because all the flats in the head combustion chamber are all .110" below the head face.

Even though the flats are all the same in the heads, the combustion chambers are a little different in cc's. Because rod #4 is so short I may shuffle it to a combustion chamber that is smaller in cc's than the others to attempt to balance the compression ratios from cylinder to cylinder.



Still clear as mud right?

Just spitballin.....why not play around with the big end center line and get the lengths equal? index the crank first of course and then even the lengths of the rods with the big end placement. Bad idea?
 
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What is your goal for power production ? What kind of torque curve ?
 
if you didn't do any of that, and kept the rpm maxed at 5500 rpm, it wouldn't matter too much would it? It would affect longevity, and smooth operation, but the bearings wouldn't suffer immediately would they?
I don't think it would cause any problems at all.

Just spitballin.....why not play around with the big end center line and get the lengths equal? index the crank first of course and then even the lengths of the rods with the big end placement. Bad idea?
If I had the equipment to do so I would have tried to make them all the same length. However I'm dependent on others to rebuild the rods.

What is your goal for power production ? What kind of torque curve ?
I have no idea what this engine will do. I've never built one like this. We'll test it with the stock cast iron intake and HP exhaust manifolds, shop headers and two or three different aluminum intake manifolds.
 
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I guess my question should have been ...
What is it going in ? Truck , hotrod , cruiser ?

Please post a picture of that 4x4 T&C wagon . I have to see that ...lol
 
I guess my question should have been ...
What is it going in ? Truck , hotrod , cruiser ?

Please post a picture of that 4x4 T&C wagon . I have to see that ...lol
We've had this original 400 big block '73 Dodge Charger sitting out back with no engine for some 10 years....going in that.

Then here is the 4x4 Wagon...................

T&C 4x4 002.JPG
 
I've run 2.25"/1.81" valves in factory iron heads before. This time I'm using 2.20"/1.84" valves. I wonder how much cylinder wall to valve clearance I have at .700" lift.

400-450 vlv 2 cyl wll 005.JPG


Intake valve..........
400-450 vlv 2 cyl wll 003.JPG


Exhaust valve............
400-450 vlv 2 cyl wll 008.JPG


As the plan is to run about .550" with a solid flat tappet we seem to be really safe.
 
I don't think it would cause any problems at all.


If I had the equipment to do so I would have tried to make them all the same length. However I'm dependent on others to rebuild the rods.


I have no idea what this engine will do. I've never built one like this. We'll test it with the stock cast iron intake and HP exhaust manifolds, shop headers and two or three different aluminum intake manifolds.

Well that splains that Lucy!
 
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