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Settled for a 440

I don’t think that I would use that balancer with a chunk broken off of it and the elastomer ring appears to be separating.

Okay thanks for letting me know. I did notice the chip. New balancer it is. I wonder if 440 source's is any good...
 
Just pop for a new balancer best thing you could do. I would never put an old one on and refreshed motor. We went 20 over on a stock bored 383. Could not find flat top piston's. so put half dome in the motor. What head's do you have. If you have the 906 head's their is room. Your engine shop should be able to tell you if that is an option.

Thanks for the recommendations. I will buy a new balancer. I have seen 20 over KB pistons, but I do not know if they are any good. I have 906 heads, and I could ask my machinist about the pistons.
 
Thanks for the reply Jerry. You are correct. Next stop is the machine shop. I have seen Keith Black pistons that are 20 over. I am thinking 20 over to leave myself with more boring potential in the future.
See what's available in 10 over also. I honed my last 440 standard bore build as the cylinders were still true and only a few thousandths out and used file to fit rings on the stock pistons. Sure it was a PITA, but I still have a basically stock block.
 
It's not a steel crank damper. Get a new one. The motor price seems good for today. An .030 bore should be good. A quality machine shop will tell you what it needs.
Don't think any of my 440 cranks had casting numbers. Stand it on end, with no damper bolt, tap each counter weight with a hammer, listen to see if it sounds like a tuning fork. I they all ring like a tuning fork, the steel crank is good. Then just get it ground to the size that works.

Thanks for your comment. I am thinking .020 or .030 bore, whichever one is the lowest I can go. Yes I plan to go to my machine shop soon. That's good to know about the crankshaft. I will have to try that to see if my crank is good.
 
See what's available in 10 over also. I honed my last 440 standard bore build as the cylinders were still true and only a few thousandths out and used file to fit rings on the stock pistons. Sure it was a PITA, but I still have a basically stock block.

Thanks for the reply. I haven’t found any 10 over pistons. The lowest I have found are 20 over KB pistons. I have not heard of filing piston rings before. I will have to read up on that. A stock block is great!
 
If you can go with a .020 overbore, forged pistons that's real good. Mopar blocks didn't wear much but some weren't as square as I like. The closer you can get to stock bore the better. Thicker cylinder walls make more power. File fit rings are real common. Takes patience to get them right. Ring filer tools are readily available at fair prices.
 
Something to remember, certain types of rings are very fragile. Take care when filing and installing on the piston.
 
If you go with the half dome piston's. You need shorter length on the spark plug electrode's. One of my pistons was just lightly touching my spark plug. Bought AC Delco with shorter electrode. Good luck on the build wish you the best. 440 source is a good place to get motor part's.
 
The first oversize in a "Off the Shelf" forged piston will be 0.030". A "Custom" forged piston can be whatever size you want. The KB pistons are a good choice for a street motor, but need the top ring gap opened up due to the configuration of the piston, "Heat Dam", that isolates the top ring and not to mention the higher silicon content of the piston to reflect heat up towards the cylinder. On average, the top ring will need to be opened up to 0.026" to 0.028" gap.

Filing the rings is not difficult, but depending on what you have to use, care and patience counts. A simple flat file placed vertically in a vise can suffice. With the gap away from you, squeeze the ring onto the file at the portion of the file closest to you, and to carefully proceed to push the ring towards the vise. Once you finish with the stroke, release pressure on the ring to open the gap, and start over. NEVER stroke the ring back towards you as you will damage the moly coating on that type of ring. In order to maintain parallel ring ends at the gap, you squeeze the ring together and look up to the light to see how you are doing, and adjust stroking angles in order to keep the ends as parallel as possible. Before you put the ring into the bore to check the gap, use a small file to dress the 8 edges (top, bottom, in, and out) on both sides. Just a few strokes will suffice to break the sharp edge, and once again, only file into the Moly outside edge so as not to lift the coating.

In order to "square" the ring in the cylinder to check gap size, put the oil rings or second ring in a piston, and use it to push the ring being checked so it is square in the cylinder. The oil or second ring acts as a stop so the piston itself is square also. If you have (or get) a hand rotary filer which is inexpensive, the work will go faster, but you still need to adjust the angle of the ring end to maintain the parallelism of the ends. I would stay away from the cheap Chinese electric filers as they are JUNK!!

Steel rings are even more fun. It took an hour to file just one Cummins top steel ring by hand so I sprung for a professional electric filer...

Ring Filer.jpg
 
If you can go with a .020 overbore, forged pistons that's real good. Mopar blocks didn't wear much but some weren't as square as I like. The closer you can get to stock bore the better. Thicker cylinder walls make more power. File fit rings are real common. Takes patience to get them right. Ring filer tools are readily available at fair prices.

The 20 over pistons I have found are KB Hypereutectic pistons. I will keep searching. Thanks for telling me about filing pistons. I have not had any experience with them. Thank you
 
If you go with the half dome piston's. You need shorter length on the spark plug electrode's. One of my pistons was just lightly touching my spark plug. Bought AC Delco with shorter electrode. Good luck on the build wish you the best. 440 source is a good place to get motor part's.


Thanks for your reply. I will keep that in mind when looking at half dome pistons. I have been looking at 440 source for engine parts, as their prices seem very reasonable. I have read that the quality on their parts for the most part are solid.
 
The first oversize in a "Off the Shelf" forged piston will be 0.030". A "Custom" forged piston can be whatever size you want. The KB pistons are a good choice for a street motor, but need the top ring gap opened up due to the configuration of the piston, "Heat Dam", that isolates the top ring and not to mention the higher silicon content of the piston to reflect heat up towards the cylinder. On average, the top ring will need to be opened up to 0.026" to 0.028" gap.

Filing the rings is not difficult, but depending on what you have to use, care and patience counts. A simple flat file placed vertically in a vise can suffice. With the gap away from you, squeeze the ring onto the file at the portion of the file closest to you, and to carefully proceed to push the ring towards the vise. Once you finish with the stroke, release pressure on the ring to open the gap, and start over. NEVER stroke the ring back towards you as you will damage the moly coating on that type of ring. In order to maintain parallel ring ends at the gap, you squeeze the ring together and look up to the light to see how you are doing, and adjust stroking angles in order to keep the ends as parallel as possible. Before you put the ring into the bore to check the gap, use a small file to dress the 8 edges (top, bottom, in, and out) on both sides. Just a few strokes will suffice to break the sharp edge, and once again, only file into the Moly outside edge so as not to lift the coating.

In order to "square" the ring in the cylinder to check gap size, put the oil rings or second ring in a piston, and use it to push the ring being checked so it is square in the cylinder. The oil or second ring acts as a stop so the piston itself is square also. If you have (or get) a hand rotary filer which is inexpensive, the work will go faster, but you still need to adjust the angle of the ring end to maintain the parallelism of the ends. I would stay away from the cheap Chinese electric filers as they are JUNK!!

Steel rings are even more fun. It took an hour to file just one Cummins top steel ring by hand so I sprung for a professional electric filer...

View attachment 1164709

Thank you for all of the information!! Glad to hear that the KB pistons are good for street use. I do not know if forged pistons are worth it for my expected use. I would be using my car as a street machine/cruiser with probably no more than 450 hp.

Thanks for the instructions on how to file rings. I will definitely come back to your post when the time comes to start filing my pistons rings.

I can only imagine how tedious a job like this can be. Will stay away from the cheap electric filers!

Thanks a lot!
 
Although I've never run a hypereutectic pistons, hear they work well on moderate CR street motors. Manual ring filers will work finw.
 
Although I've never run a hypereutectic pistons, hear they work well on moderate CR street motors. Manual ring filers will work finw.
Agree.

For the power levels the OP is talking about, hypereutectic pistons will easily handle the power his engine will make, and they can be tighter in the bore than a forged piston since they do not grow as much with heat as a forged piston does. I put hypereutectic pistons in my 340->416 stoker build I just finished. Aluminum heads, blah, blah, blah, but a mild build making in the 400s for horsepower. The pistons will easily handle that all day long. @RockyPat stated you are on a budget, and hypereutectic pistons are also cheaper than forged. Spend money where you need to, don't spend it where it is not.

Power also comes from all the geometry of the block being correct. So check the deck height and see if it is consistent for all pistons. Also, boring can true up bores that are not perfectly perpendicular to the crank (although I'm not sure I would bore a lot just to do that).

Bottom line as many have said: Get the block checked before buying any parts. Then, based on the geometry of the block and the type of build you want, choose machining and parts as needed.

Good luck with your build!
 
Although I've never run a hypereutectic pistons, hear they work well on moderate CR street motors. Manual ring filers will work finw.

This is good to know! Thanks for your comment. I will ask my machinist what he thinks about hypereutectic pistons. I will look into manual ring filers.
 
Agree.

For the power levels the OP is talking about, hypereutectic pistons will easily handle the power his engine will make, and they can be tighter in the bore than a forged piston since they do not grow as much with heat as a forged piston does. I put hypereutectic pistons in my 340->416 stoker build I just finished. Aluminum heads, blah, blah, blah, but a mild build making in the 400s for horsepower. The pistons will easily handle that all day long. @RockyPat stated you are on a budget, and hypereutectic pistons are also cheaper than forged. Spend money where you need to, don't spend it where it is not.

Power also comes from all the geometry of the block being correct. So check the deck height and see if it is consistent for all pistons. Also, boring can true up bores that are not perfectly perpendicular to the crank (although I'm not sure I would bore a lot just to do that).

Bottom line as many have said: Get the block checked before buying any parts. Then, based on the geometry of the block and the type of build you want, choose machining and parts as needed.

Good luck with your build!

Thanks for the outline! Nice to hear that the hypereutectic pistons are working well for you. I think they should for me too, as you have said. I agree with not spending money where it is not needed. I will definitely make sure to have my machinist look at the block, crank, etc. I will go from there, and hopefully he will have good feedback for me! I appreciated the advice.
 
Thanks for the reply Jerry. You are correct. Next stop is the machine shop. I have seen Keith Black pistons that are 20 over. I am thinking 20 over to leave myself with more boring potential in the future.
Agreed - If the block truly does need to be bored, then bore it the absolute minimum needed to have a clean, true bore to be serviceable. Not just for ability to "redo" it down the line if necessary, but to retain block strength, rigidity, avoid having hot spots and resultant overheating. If/when I need mine done ('78 casting 440), it will hopefully just need +.020. KB makes great selection of .020 oversized pistons as does Silv-o-lite and others. Good luck with your build.
 
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