Just went into the shop & checked about 9 350 blocks with caps all are factory numbered 1,2,3,4,5. I have built at least 2 dozen sm blocks since the 70's I don't remember any without numbers, I could be wrong but.....
Pretty hard to get the caps in the wrong place. maybe on backwards? That is why I suggested that clearances should be checked. Instead of guessing what may be wrong start at the beginning and find out what may be correct. Some of the fellas here are pretty sharp most of them sharper than I am but I know from experience that no one knows what has been done from where they sit. Suggestions can be made but to figure it out one should start at the startin place.
Put the crack pipe down and step away from the engine stand. I don't know where you heard that information but shoot the guy who told you that and put him out of his misery. This time period is when I was the most heavily involved in racing and NEVER did I or any of the fellows I built engines for EVER turn a new chevy crank .060 to reduce friction. After having set and building engines for a number of National Record holders during that time period your statement ranks right up there with the beliefs of the "flat World Society. The ball is in your court. Frank
well, lets take a look at this step by step. First off, its $129 theres no good reason to spend, that could be used for something more productive. Secondly, he already has a perfectly good crank on hand, why order one from summit and wait a week for it to get there? I would say that should about cover it. If you, or any other HAMBer for that matter, have $129 that you really have no idea what to do with, and have no further use for, please feel free to send it to me, and I PROMISE I will put it to good use buying car parts. You have my guarantee on that.
Plasitgauge is more than accurate enough to show if you are within tolerance for the average garage builder. Stock main bearing cleanances for a 350 are .0008--.0015 and # 2 and 4 mains are .0011--.0023. At least that is what my manual says. Plastigage is more than accurate enough to let you know if you are out of tolerance and need to get a mic out to check closer.
The clearances might be too tight based on these numbers and my plasticguage measurements. Either way, the crank is still not turning as easy as I'm being led to believe. I even took the main bearing caps off and tried to start over. Its become pretty clear I need to pay a visit to a machine shop because I have obviously exceeded my pay grade. Many thanks to all those who have contributed. You all have been a HUGE help!
On a sbc, for what most people do it'll be FINE, however it should be noted that a 350 likely has a cast crank so i wouldnt trust it as much as say my small journal forged crank that is .030-.030 Just my opinion though, i havent really broke enough to be called an expert
Do you think that removing and extra .020 from a journal (.030 vs .010) is going to make a noticeable difference in the strength of a crank? In fact if you spend some time and make the fillet radius bigger while doing the grind its probably stronger. The problems I have seen with buying regrind cranks on line is the quality... yea they are cheap but you get what u pay for. If Summit can sell it for $129 what did they pay some shop to clean inspect grind and package it... $75-$80 maybe? And that shop has to make a profit, think they are spending a lot of time on each one? Guys used to bring them in (cheap regrinds... not saying Summit)to my shop and many of them were scary... measured different for very journal.. most journals had taper and or were out of round, none were chamfered and some of the radius's were just scary I even see some that werent polished after the grind. Crank grinding needs to be done by someone who knows what he is doing... when you find a quality crank grinding shop stick to it as they are getting harder to find these days. It will cost a little more but its worth it.
Wow! None of you guys ever polished the jounals on a crank using the "shoelace" method??? I must be older than dirt...
I don't know how well that would work today. Nylon doesn't make a very good polisher. I have used a cut up leather belt before.
If you installed one or more pistons before the crank seized you may have the rods turned around. The bearing is offset toward the center of the journal to provide clearance for the radius. If the crank seized before any rods were installed, Did you put the thrust bearing on the correct journal?
Sure, those fat white cotton ones used in hi-top sneakers. Another old timer used to clean crank journals with sanitary napkins to make sure all the polishing grit, etc was off. Bob
This is why I very deliberately mark everything before it comes apart, take notes and draw cave sketches so it goes back together in the same order. Of course hind sight is always 20-20. Lately I use the good old digital camera to capture anything important. Bob
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