also wanted to see everyones take on using bearing spacers on a high rpm motor? (350 main to 283 main) or would I be better off using thick bearings. (cost more $$$) what would a safe rpm assumption be on the spacers? THX

 

I don't know why it would be a problem.

Why do you want a small journal crank?

 

can get a good deal on a bryant crank 3.268 stroke with bb snout and lightened to around 35 lbs. but kinda wanna try it in an 87 roller block. or may just find a 327 block? but I like the roller setup better so far because of cam duration.

 

One of those "one race only, big-name team" deals off eBay?

Don't sink alot of money into a motor around it, if it is. There's a reason they change them out after a race and sell them cheep.

Bearing spacers are not a problem, if properly installed. They make measuring for proper clearance a little more troublesome (possibility of introducing errors). Other than that, they work fine.

 

any idea of how high you can spin a motor with spacer before getting worried?
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I talked to a guy at hendericks ms where alot of the cranks come from there is no problem using them but when you are going for a check as big as nextel you can never be too cautious especially with their bank accounts. Their would be no problem with them but I am not looking to spend a whole lot anyway around $3500 or so. not sure if I want to switch out my 406 yet anyway (especially since I haven't even heard it run yet, LOL)

 

also as far as checking them out that won't be a problem I work at Atlas Crankshafts we do cranks for ford, caterpillar, military. But most of our grinders are cnc so can't really do sbc branks since they are set up for v12 and v16's. but our metullargy lab is open to me. also callies is down the road.

 

RPMs with spacers is not an issue.

The identity of your employer isn't going to be able to scare the steel in that crank into not cracking from the abuse it already has in its history. As to whether it wil show up in a metallurgy test of some sort, I have no idea. All I know is, if those cranks were any good for anything, you wouldn't be able to pick them up for so cheeep on eBay all the time. There's a reason they're not going back out onto the track; and there's also a reason they're so cheep, and you can bet your bottom dollar, it isn't because they like you so much.

 

without trying them who's to say it is any better than a forged eagle or scat crank? for the small amount of track time it would see a year from me I think it would be fine. plus mine would be coming straight from Hendericks not Ebay so who knows that may help?

 

Yeah who's to say....

I don't think that just being on eBay, as such, deteriorates cranks any; so whether it passed through eBay or not doesn't make a whole lot of difference. It still is what it is: a used part that its prior owner is disposing of because it can't be trusted. Now granted, that owner puts it to a whole lot more rigorous use than any of us here is likely to, and has alot more on the line if it fails; but all the same, the fact remains, if it could be trusted, it wouldn't be being disposed of. So the risk is till the risk.

I hope it works out well for you; but like I said, I wouldn't go putting a whole bunch of money into making that crank work if I was you, because for all you know, first pass down the track, you could be looking for a new crank and whatever else besides. Bearing spacers don't count as "a whole bunch of money" although you probably need something other than regular small-journal small block bearings to fit that crank. Rods with Honda-sized big ends but 6.xxx length, balancing, and so on, that sort of thing is what I'd advise against sinking gigabucks into.

 

well taken and on the big bucks I was talking about the oversized thickness on the bearings not the spacers. king and clevite both make them. they are bearings that are pretty much spacers and bearings all in one. They are around $300 or so.