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ok so im just about to start building my 383 motor for the nova. im wanting help on the best proses at clearanceing the block for the rod bolts.

a step by step guide would be a big help.

i have all the tools and im ok with doing the work my self but would like to here form someone who as done it them selfs and and can tell me the do and donts!
 

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I use cap screw rods because they generally don't need any grinding done to clear the cam. And the smaller 12 point ARP bolt heads require less grinding on the pan rail than the larger 6 point nuts on standard "Through bolt" rod bolts.:yes:

As for the block.....Mock it up!! Assemble one piston and rod (floating pins makes it NICE). Wrap a SINGLE layer of painters tape around the piston to avoid scuffing and keeps the pin in. Either use an old set of bearings or just go to your local parts house and get a cheap set. Clearance is not a big deal at this point as long as they don't bind. Gently lay the crank in place and just run the main bolts down by hand. USE TONS OF THICK LUBE!!! Install the assembled piston and rod on the first journal. Slowly rotate the crank until you see the closest point of interference on the pan rail. Mark it with a Sharpe and repeat the process on all of the other journals. Once you've done all of the grinding, repeat the process on all 8 journals to check the clearance.

I've known some people who would rotate the rod away from the interference point, grind it and rotate it back to avoid a LOT of the assemble/disassemble process. I just don't like all of the grindings on my new parts.:no:

It doesn't take much grinding. A 1/4" zip tie will make a good go/no-go gauge.:yes: Just be careful no to gouge too deep on the pan rail....You'll find water!!
 

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I think Scat makes a nice stroker rod that doesn't require block clearancing.
Their cap screw rods don't require the typical grinding on the "Beam side" of the big end to clear the cam but the "Cap side" still typically meets a few different places on the pan rail of the block. The REAL nice thing about a cap screw style rod is that you don't have to run a reduced base circle cam either!! That leaves the door open to SOOOO many more camshaft options.:yes:





Clearanceing "Through-bolt" style rods for camshaft clearance.
 

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thanks D-MAN for the help!

im going for a scat i-beam rod and thay do come with 12 point cap screws.
They will minimize the amount of grinding needed but you'll still have a few places to touch......like in the top photo I posted.

Glad I could help!!:D
 

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Pre assemble and inspect. I built a 383 that had to have no clearancing done to the block. The rods were bought from Speedway already clearanced for the cam.
 

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When I did my 383 for my truck I didn't do any clearancing on the pan rail side there was plenty of room. I did have to touch the cam side of the rod because I didn't use a small base circle cam. Even used the stroker profile I beam rods and had a couple of lobes touch.

My wifes 383 I used 6" rods and hers was a 89 roller block so I clearanced the block alittle to be on the safe side. I also touched the cam lobe side of the rods just to be safe, I had the factory roller cam reground by camgrinder.

Always check and clearance as necessary.
 
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