ok...tore down a donor block that is 060 and recent build that went south really bad-major damage to head with sunk valve- rod bearing on two pistons spun- one of those ruined the crank- every rod bearing scored to some degree as a are a couple of mains. Cylinders look ok- would need to be honed.

tore down motor out of kids bronco-'83- got it done a bit ago...never been bored and i'm thnking bearings are all stock as well- copper showing on all bearings but no scoring at all- very smooth which is amazing to me given that there is metal in the pan and two broken rings. The cylinders are in good condition and there is not a huge lip from wear which has me a bit baffled- the top of the cylenders measured 3.990- can not measure inside- no tools for that yet. To me it seems like i could nearly hone this as easily as the 060- not much difference in the depth of ridge.

So....I have a great crank and rods from original motor- will buy a master rebuild kit. Using the 060 block saves me time and machine shop $$ as it is clean and should be ready to hone and go. Doubt I will have to anything but re-bearing lowr end- might have crank polished and rods resurfaced...looking for input here...

The original block would then be kept for a stroker build someday as i have a set of 4 bolt main caps etc and it is a sweet block.

looking for some advise on all aspects of what i am gabbing about as i have to finish this so i can get to my 400 build- and will start buying parts asap. Might also have another complete motor with 60k on a rebuild to consider...but am NOT counting on that cause when he says it's a strong motor he means it might hit on all cylinders.


build means all new parts cam, lifters, timin, pistons, bearings, maybe roller lifters, waterpump, oil pump on and on...just not a lot of machine work if I don't have to.
thanks

 

I gotta go with the fresh block. The 60 over's had a life already, and with damage done, it's time to put it out of it's misery. I'm doing a 60 over 302, but it's being stepped up from a 40 over and it was still running strong when I pulled it out of my '70.

 

I'm with Pete on this. Personally, I'm just really leery of going .060 over on a 302 or 351W. If you don't go through the side of a cylinder wall into the water jacket during the boring process due to core shift, you still can wind up with cylinder walls that are so thin that they can distort and cause sealing problems, not to mention the possibilty of it running hot if your cooling system isn't up to snuff.

On the other hand, lots of people report running .060 over with no problems...so you just never know.

 

Dan's got a good point. I wouldn't have considered going so far over without having the block sonic checked. Pretty cool stuff. They take a sample reading from material that they know the thickness of, then calibrate the machine to that reading, then just slowly "sweep" the cylinder walls to find the thickness. It's worth the extra few dollars any time you're boring, IMO.