The 351w I just got is standard bore. I'm taking it in to have to cleaned and tested and was told by a couple guys last night that it should be bored out .010 regardless of weather it needs to be or not as well as having the deck plained. There is no pits or scoring on the deck or in the cylinder walls. Is this advice correct?

 

I am doing mine without either, my dad has been doing them without either for 15 years and not a one has come back for that reason.

 

i work at a high performance engine shop. davesenginemachining.com moparengineswest.com

you DEFFINATELY should have the machine work done. at least have the cylinders honed if you dont want to bore them. and it needs to be decked. no questions about it.

we just got a crate motor someone brought in cause it wouldnt run for ****.

i yanked it apart and it wasnt decked. so the head gaskets didnt seal and got water in the cylinders = rust = have to bore now anyways.

moral is, get the machine work done in the first place, itll save you time, money, and headaches. second, dont buy a crate engine. they are ****.

 

^ ohh, harsh!
not that I have much experience, but common sense seems to me that the machine work listed seems like a good idea. decking esspecially

 

if your boring why do 10 id do 30 over

 

i didnt mean to be harsh haha.

i just dont want someone else to screwup. cause thats what we do at my shop, fix everyones mistakes.

 

You'll prolly need to go at least .030 simply because you can't find pistons smaller than that without getting into the really expensive or custom stuff. If the cylinders are straight enough then you might be able to get away with just honing it and staying at stock size, but I seriously doubt they're in that good a shape.

 

lol I didn't take true66's reply as harsh myself, just that of someone who, as was said, fixes other peoples mistakes. I understand the straight forwardness of replies in that sense.

If the cylinder walls need to be honed I'd like to maintain as much as the walls as I can. I see no reason to bore out the cylinder walls any more than whats required. Ok, well I can understand why some people do it but its not needed in our application (wife's street car) as it'll have plenty of power for her. We're fairly sure they'll simply suggest honing anyways.

So I'm looking at decking the block. If I reuse the stock heads (small chance here but..) those should also be decked so the mating surfaces match. This leads to another question.. What about the intake? Makes sense to me that if the block and heads are decked planed then the intake will sit high and not match the ports. Would I be correct in this train of thought? Will be adding an Edelbrock intake.

Thanks for all the advice so far.

 

if you turn the motor down .01 by machining you can possibly get by using oversized rings if you don't mind possibly a little more drag. go moly faced rings if you do and you should be good. if i were you i would grind my own rings if you do that to fit your new honed bore properly. they most likely mean hone if you are only going .01 over the original bore

 

These guys are right. The odds of a used block having perfect cylinders and deck are slim. Machining will help insure your heads and piston rings seal correctly. It is actually desirable to build out a performance motor from a seasoned block becuase everything has already moved around and settled.

Many new blocks have undersized .01 cylinders and oversize decks so that you can hone the cylinder for standard size and machine the deck true when you build out the short block. Like 67 said, if your block is already standard bore and you want to hone, you many not have much choice in boring out to .03 unless you want to buy custom pistons. I did a quick look and did not see any .01 or .02 over pistons not to mention finding the PCH or dish you want. .03 over is pretty common and there is no reason the block should not last another 100k in a DD.

I have no experience running a std piston with "oversize" rings. I would guess this would not work very well or last very long.

As for decking...Yes people do deck both the block and heads. It really depends on if the heads are used or new. If they are used, I would have them checked out. If they are new and good heads, they should be fine. I have not heard of anyone machining the intake side. I suppose there is more play on that mating surface. The standard Windsor head gasket is .041 thick. Racers and performance guys (including me) sometimes use thinner gaskets to gain a little compression. I run a .039 gasket. Depending on how much they machine off, you can gain that back in gasket thickness if you want to or simply run with a little more compression than the block used to have.