Do you engine builders here on the board mark rod caps when they're brand new? The second pic, end rod cap has a V or maybe A on the cap. I am used to marking caps when i tear down-and that's because when they were brand new and going into the motor they were never stamped. rick
The plugs still look great for a grenaded bottom end, no detonation there! While detonation is a strong opposing force, you'd still see some tell tale sign from it. Bob
The only detonation I have ever experienced caused more of a "burn through" condition, not this kind of carnage.
Phil I hate to do this to you but I took another look at those pictures and I have to agree with these guys. Those don't look like ARP rod bolts. Those rods don't look new. Nobody that I know marks rods for position if they are new. If you want someone to help you look over your next build I'm here for ya. Just let me know! But for now, I'm off for the Carlisle swap meet. I'll pick up on this thread and see ya when I get back.
I just went and looked through the paper work and it does indeed say that resized big end of rods. Why would he tell me crank,rods,pistons when I ask him what was in the kit ? It only stated that the pistons were Hyper Claimer 383 and the crank was cast steel and he balanced it. So the rod i.d. was right on by you guys.
Get a second opinion from an other engine builder. If detonation was the cause the spark plugs and rod bearings will show it, not just a burn pattern. Also maybe it's the pictures but the cilinder wall finish doesn't look right. And as i said before check the lenght of the piston pins, in that one picture it just doesn't look like a 3" pin in a 4.060" bore. That he used stock rods is one thing but if he also used the stock rod bolts and not ARP bolts that would be realy risky(stupid). And get a new engine builder....
I have had several major failures like this in my road race cars - one thing I can tell you is you will NEVER know the exact cause, as parts are too badly destroyed. Move on, start again, and get on with life. But, ALWAYS know what your timing is - I usually set at full advance, but you need to know whole curve, 'cause you can get into trouble at partial advance also. And be very careful with parts you re-use - I've seen a lot of engines promptly blow up again because schrapnel was not entirely removed. Generally, you can never get an oil cooler, pushrods, and lifters clean......
Phil, Ive been waiting to hear something about balancing. I see no less than 6 rods on the first page of your thread. There are NO signs of any weight removed from the balance pads on the 6 rods??? The rods are stock, and the bolts also appear to be stock, but moving on about the balancing aspect. I'll very gladly admit, there are thousands of guys here that have seen and rebuilt more stockers than I have ever even seen. That said, the maybe 5% of my engine building career, and the balancing Ive done with stock{ performance reworked } rods, there has always been some amount of material that needed to be removed from the big end as well generally as the small end. Regardless of the increased bore size, change of stroke, what have you, stock rods will require some weight removal to bring into any kind of parameters necessary to balance a rotating assembly. Carrillo, Lentz, Callies, Crower, these can come from out of the box plus or minus 1 or even 2 grams on the big end, but not stock rods, not even close. Harmonics can break a 4340 Billet crank, imagine what it can do to some Claimer Hyper Pistons. Second, I would like to say this because of the mention of dyno tuning elsewhere in the thread. It saddens me anytime ANYONE has to experience what Phil has been going through. The $500 for a few hours on the engine dyno is well worth it, and this is just one example, I;ll explain why. I am very confident in saying, at least on my dyno with a " KNOCK SENSOR " on each cylinder head, that missfire at 5000, probably would have pegged the sensor needles to red-line!! From that point, you stop, shut the engine down, pull all the plugs, cut open the oil filter, and try and diagnose why. Yes, in this case as well as many other times, the engine would eventually need to be torn down, and completely gone through again, this time by a more experienced builder. The good news it would only cost time and a gasket set, and not a new rotating assembly or parts of it. This case the block is trashed also. I'm sorry Phil had to experience this, and hope they truly get his engine going again without any further issues, TR
Did you say that it was .060 overbore ? That seam's like an awful lot for a 350 block .That wall look's very thin where it failed .
I stripped down my other 3970010 block and dropped it off for hot tank and magnuflux. My crank is still good out of the blown up engine 375 stroke. I was offered a set of forged JE pistons 60 over for a 6.0 rod and a 400 crank, my crank is a "400" crank correct ? So I would need to come up with a set of 400 rods to make this combo work ? The dampner and flex plate should also work on this combo ?
Most stock SBC rods are 5.7", the stock 400 rods are shorter. So you would need a set of 6" rods. Might be quicker/easier/cheaper to but a set of good pistons and use your rods, with new bolts.
Are any of you guys having trouble with going 60 over on a 350? We have ran into cracked cylinder walls with a couple and just wondering about this guys problem. I have also grenaded one that had a miss like that just at the top of the gear change. I didn't go with my gut and it blew one pass later.{wrist pin}
The piston could have hit the garbage flying around from cylinder to cylinder caused the pistons to frag? It could have started with something falling down the intake or from hydraulic pressure if the head gasket went A Buddy hauls cars. he put a 2 barrel carb on a used 1994 ford 460 to convert it from fuel injection. His third or 4th trip out it started running with a miss and using oil. when he got home his oilpan has a little of the junk i see in yours but there was a piston completely missing. the rod was there and the pin was gouging into the cylinder wall but hadn't got into the water jacket yet... but the piston was completely gone except for a small portion of schrapnel in the pan. He figgured his was detonation since fuel injected 460's run about 10.5 or 11:1 I'm running KB flat tops in my 460 with 1977 heads for about 10.75- 11:1 I can;t run anything with less than 91 octane or it will ping but I've got 20k on it and just swapped head gaskets. The detonation froma sticking thermostat helped burn out the fire ring on my #7 cylinder and a small piece of the piston crown at the ring land was chipped off.. but i just slapped on gaskets and she is still running strong. when my thermostat went bad ti was not overheating just running too hot but not boiling out
Out of curiosity when you let off the gas how far did you let off? And did you clutch in as well? IIRC normally the failure I'm thinking of would break the rod. High revs + closed throttle + no load = broken rods. I'm a little beat so I may be off. But if the pistons were weaker than the rod...
You shouldn't have any detonation running 91 octane or better with those head and those pistons looks like a 10:1 engine at the most. I'm going to go with something got between the piston and the head causing the pistons to totally fragment. Can't say what it was. If your pistons were set too hight on the deck the carbon would be washed away from the squish. and if the pistons contacted the heads... you'd see piston reliefs in the head and see the outline of the combustion chamber hammered into the piston tops. It looks liek the kind of damage from when the pistons slap the heads except for any evidence showing the piston touching the head. but theres lots of evidence the piston hit something that was between it and the head. I'll bet it was a simple thing that cascaded into a catastrophy
That theory doesn't explain this piston: To my thinking, it did not fail in compression. Looks more like a failure in tension.
Could have cracked between the oil drain holes from something (Pressure wave from detonation?) hitting the top. And then pulled free under vacuum
I'm a bit late to the party but I don't see the normal signs of detonation that should be present in more than one cylinder. No damaged insulators on the plugs and no normal erosion of the piston tops. One scenario might be that the top ring in that cylinder either missed getting gapped or missed getting gapped correctly due to one reason or another such as a phone call or customer walking in and breaking the routine. What ever happened that is one of the best jobs of grenading an engine and not loosing a rod bearing that I have seen.
Ive been waiting to see if anyone would question - PISTON TO WALL CLRNCE. These modern claimer CAST pistons run a fairly tight PTW, even slightly more so, the coated ones. Now, you take a loose or excessive PTW clrnce., these CAST pistons will rock back and forth in the bores, and DO NOT handle side loaded very well, and yes they can and will self destruct as in the pictures. It will happen fast and violently. Old CAST pistons were made with steel side plates cast inside the piston, "partially" for just this reason. There are several resons for the side plates. Now a days, with modern honing equipment, dial bore gauges reading to .0001", its easy for a good machinist to closely hone these cast pistons to thier respective cylinders. Between this and better alloys and improvements in modern design, Cast pistons generally no longer need these reinforcing plates, at least not all of them. The old days the routine was to hand hone and then stick a piston in the cylinder, and a strip of feeler gauge was pulled between the piston and bore. Now we can still check Phill's remaining good cylinders and pistons for the PTW clrnce, but these might show in spec. The cylinders and pistons that self destructed are probably not able to be checked for the running clrnce that was honed into them. I'm not saying this is definatively what happened here, just more to think about. Probably not, Piston-to-Head, one of the very first things I considered, and as mentioned there are no signs of that occuring, TR
get out of here with that avatar of yours, we can't consentrate on broken engines with that thing hanging around lol I picked up the empty block last Friday and spoke more with the builder. He wants to make things right for his name sake as well as customer relation. The new block is being hot tanked and magged this week, I told him I didn't want anything to do with these pistons this time around.
Ya know what I have not heard about yet is the cleanliness of the shop that built the engine, that the shop is well lit, the floors are clean, short block looked properly (obviously, only from what I cold see) assembled, piston/deck height looked good, plus the builder is more than willing to work with Phil. Doesn't look like a fly by nite operation to me. Did the owner assemble the short block or did a helper? If the pins were press fit, were they pressed into the rods or into the pistons? Without going on and on (oh, by the way, specifically, who made those pistons? Don't tell me a "jobber". Gotta come from some one and somewhere) "claimer" pistons, rods, etc. are the best that a certain amount of money will buy. And they will be sourced from all over the world. Hate to ask this but how much did the short block cost? Specifically, how much did each parts group cost (set of pistons, set of rods, crank & bearings, etc.)? Along with machine work pricing? Might be nice to sonic test the cylinder walls. Come to think of it, is the crank stright? Was it sent to a grinder and put on v blocks and really checked? Put in a machine and had the throws checked? I'm sorry swade41/Phil(?) if I have asked too many questions. Sometimes shit just happens. My feeling .... tight piston/pin clearances. Someone could have assembled them, found one a little tight and said "it'll will wear in". Best of luck, John
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