512 Build

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Garys72Duster

Garys72Duster

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Starting a 512 build. So far, of the 3-400 blocks I have, 2 are .060 over and 1 is .030 over. So will get them sonic checked to see which one has the thickest cyl walls and go from there. One of the .060 over blocks has very little wear, was a truck block, and the pistons are like new. ICON has pistons in .033, 040 and .060 oversize. IC823-040 is the one I like. I can get 13 to 1 C Ratio with that flat top piston :usflag:
 
What years of 400 blocks do you have? I have always heard the earlier ones are bad to be thin on a couple of cylinders but I forget which cylinder numbers. Care to share your findings with us? I know that A/R engineering has already done some research concerning wall thickness in blocks but more information is always better.
 
Here is a pic of my earliest one. Has the strongest mains, but it's already 60 over with about six thousands of wear. I wont even sonic check this one. Prob work as a street 451.
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The other 2 are 530 blocks from 1975. I'll let you know what the cyl wall results are. If the .060 over block has thick enough walls, may just have that one honed, and put in New ICON .060 OS pistons.
 
Wow! 230 cold weather block, casting date two months before they went to the smaller main webbing. Looks like may be a very light sign of cap walk on that one main journal. If your building a 13:1 race engine, it would almost be worth it to sleeve that one in the thinnest cylinders. A BCR main cap and girdle kit would make that the strongest factory production block imaginable, possibly even strong enough for a set of B-1 original heads.
 
Garrett Ellison said:
Wow! 230 cold weather block, casting date two months before they went to the smaller main webbing. Looks like may be a very light sign of cap walk on that one main journal. If your building a 13:1 race engine, it would almost be worth it to sleeve that one in the thinnest cylinders. A BCR main cap and girdle kit would make that the strongest factory production block imaginable, possibly even strong enough for a set of B-1 original heads.
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i was thinking sleeves for that early block too :thumbsup:
 
Garrett Ellison said:
Wow! 230 cold weather block, casting date two months before they went to the smaller main webbing. Looks like may be a very light sign of cap walk on that one main journal. If your building a 13:1 race engine, it would almost be worth it to sleeve that one in the thinnest cylinders. A BCR main cap and girdle kit would make that the strongest factory production block imaginable, possibly even strong enough for a set of B-1 original heads.
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Yes! That's the one I was going to use for my 512 build, until I pulled the heads off, and found 60 stamped on the pistons. Ha! Now I don't know what to do with it. Anyone want to buy it, and sleeve it?
 
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How much would you have to have? Sonic check it first to see what you got, it’s doubtful, but there may be enough metal to use an oversized ford 429/460 piston that uses a .990 pin. More than likely there is already one or two cylinders that are thin and need sleeves already. You never know though, sometimes you get lucky.
 
Well I paid $1000 for the motor with a 727. Not much else that can be used, other than water pump, oil pan, and a few brackets. I would like 500 for the block. May sonic check it after we check these other 2- 400 blocks. Need to get a block to the machine shop, and order pistons soon. It's almost March! Yea!
 
Ok, I checked the .060 over 230 block, and the .030 over truck block. Looks like they are both usable! So will try the truck block, and go another .010 to 40 over. Here are results of the sonic test.
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Only one a little thin is #2, only .186 at top, Which seems unusual since all the others on that bank are in the .200s at top and 200s at bottom. He may have wrote that one down wrong.
 
That seems reasonable, I read that one of the cylinders always came up thin on the right bank, I have read its usually numbers two and four on the 230 blocks, IIRC.
 
Did you have the readings of 230 block? Just curious how much is left in the bored after a .060 over.
 
Garrett Ellison said:
Did you have the readings of 230 block? Just curious how much is left in the bored after a .060 over.
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Sure, here they are. Looks like this one could go another .020
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Filling the bottom half of the water passages with block cement would strengthen the walls enough for it to go up to .080 oversize. On an all out race motor, may want to fill the block up with cement to near the top. This 230 block has not seen it's last day yet! LOL
 
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Wow, those are some impressive results for a .060 over block, that would make a good drag type engine with the jackets filled.
 
Yes! I wonder if you filled the jackets to about 1" below the deck, you could still run a water pump, and cool the cyl heads, Right? That would help, since the heads get a lot of heat. Maybe even just run an electric water pump? Would that work?
 
It would be doable in a short cycle engine as long as there were no head bolt or reinforcement bosses protruding downward from the deck that would cause the water jackets to get blocked. A flow cooler pump and aluminum heads would help, but not as much as an external oil cooler. The most important thing to do is to talk to your piston and ring tech support. The piston to wall clearance and the ring end gap clearance both need to be opened up to at least air cool settings, and a little extra doesn't hurt. How much wear do the cylinders have as far as oval and taper? .060 over pistons with file fit rings may still work. With a BCR girdle and caps, aluminum rods, and red line 50 weight oil, I wouldn't be afraid of running it on ethanol with 15:1 SCR and B1 heads, but numbers 5 and 6 would be the go-no go gauge according to if they needed sleeved. Anything is possible, but if it costs almost as much as an aftermarket block...
 
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What would be the recommended piston to wall clearance on the 530 block, at .040 over? I'm thinking .005 to .006". Is that enough on a 6500 RPM motor? 13 to 1 C Ratio, Stage VI alum heads, Roller Cam, tunnel ram. I want to run them as tight as practical, to reduce piston rock/slap. ICON 823-040 Premium flat tops.
 
That piston is 2618 aluminum, which requires a little extra clearance for the higher expansion rate. I would err to the large side of the tolerance specs at 13:1 compression, a little piston slap/rock is a lot better than scuffing and cold seizure. If building tight, I like the looks of the Mahle pistons with the skirt coatings and metric rings, but they are pricey, P/N 120375F08 on this list. http://www.us.mahle.com/media/motorsports/bbm-web.jpg
Mahle shows piston clearance of .004-.005. Here is the list for Icon from the friendly folks at hughes, notice the drag race specs, which is what I would think a 13:1 512 would be, .006 to .008.
http://www.hughesengines.com/Upload/productInstructions/iconinstallation.pdf
 
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I've been wanting to do a 470 build for a while, so I have looked at piston options pretty hard. I got to put Mahle pistons in a few bike builds before, I like their products.
 
Garys72Duster said:
What would be the recommended piston to wall clearance on the 530 block, at .040 over? I'm thinking .005 to .006". Is that enough on a 6500 RPM motor? 13 to 1 C Ratio, Stage VI alum heads, Roller Cam, tunnel ram. I want to run them as tight as practical, to reduce piston rock/slap. ICON 823-040 Premium flat tops.
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I am assuming based on the math that this build takes a 4.25 inch crank, 1.12 compression height, and rods in the 6.7 inch range. I wasn’t able to find your piston listing, but haven’t tried too hard yet.
 
I wish I had the cubic Dollar$$$ to fund the cubic Crazy. I’d like to take one of those 230 blocks and do an all out on it to see what it could do before the block split at the pan rail...
 
Garrett Ellison said:
I am assuming based on the math that this build takes a 4.25 inch crank, 1.12 compression height, and rods in the 6.7 inch range. I wasn’t able to find your piston listing, but haven’t tried too hard yet.
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4.25 stroke, 6.535 rod, 1.322 C Height. Go to Summit, type in IC 823-040. It has all the specs. That's the piston I like. And yes you are right, it is the 2618 Aluminum Alloy.
 
Garrett Ellison said:
I wish I had the cubic Dollar$$$ to fund the cubic Crazy. I’d like to take one of those 230 blocks and do an all out on it to see what it could do before the block split at the pan rail...
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Probably need to be over 1000 horsepower to break them. I think they begin to split/crack between the crank main journals, and cam bearings. That's where these 230 blocks have the added strength.
 
That’s a good build combination. I like the 1.32 inch compression pistons, it’s better to have the stability of the full skirt with that much stroke. Are those the Chapman Racing stage VI heads? With the quick revving light no weight and the 1.54 rod ratio, airflow is everything, no such thing as too much cylinder head!
I imagine that one of the 230 blocks with a full fill (no cooling) and the BCR caps and girdle would be good for upwards of 1500 hp.
 
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