building

[shockcocker04]

i just plastigauged my mains and every single one was .003? is that ok? also i had to space the main brace with washers to clear the 4.2 crank. i also wanted to know the effects of not dishing the pistons. i did not dish my 677. sry if some of these topics were addressed im just freaking out lol im only 19

thanks alot guys

[oletshot]

I'm guessing the crank wasn't just reconditioned, if it was I'd ask the machine shop about it. Spec is .001-.0025 (.002 prefered). You can get a .001" undersized bearing according to my manual. Probably dealer item (if you wait you can pick em up cheap at their "going out of business sale", OK not funny), I've never needed them so I'm not sure. I myself would probably just go with it, it's only a half a thousandth over, a little extra clearance is always better than not enough.

Dishing the pistons lowers the compression ratio. High compression motors require higher octane fuel to keep from detonating. It also equals more power.

[shockcocker04]

thanks alot, the crank was reconditioned and im using 20 over bearing because the crank was 20 under. what oil is best for break in? i was going to use 15-40 diesel and continue to use diesel?

thanks again

[SilverXJ]

What is the API rating on the diesel oil you are considering? For break in I would suggest a good CI-4 diesel oil or something like Brad Penn or Joe Gibbs oil plus a bottle of GM EOS, Crane cam's cam break in or comp cam's cam break in fluid. I would also add one of the additives at every change. Also be aware that the cam break in procedure is different from the engine break in.

[shockcocker04]

im not sure the api but ill be using penns, how is the cam break in different from engine break in?


thank you

[seanyb505]

Cam break-in you rev the engine to about 2k while in neutral and hold for about 20-25 minutes then drain oil. You have to drain it while its boiling hot so you get all the bad stuff out. jk, dont do that. Engine break-in is where you drive it around, varying engine speed. You'll want to load the engine in 3rd gear or so, accelerate to 50, let off and let it deccelerate. Let the engine slow the vehicle down, not the brakes. Repeat that about 10 times or so to get the valves and other friction surfaces to seat properly.

[shockcocker04]

yea lets not drain the hot oil, lol i understand the break in now. what kind of reliability can i expect from this engine? as a daily driver and weekend warrior?


thank you so much

[seanyb505]

If you break-in everything properly, use the right oil, take general care of the engine, it should do fine as a daily driver.

[shockcocker04]

use the right oil? i want to run 15-40 all the time?