What all has to be done to a block (sbc) to prepare it to build up for about 350 HP? About how much would the machine work cost me and how much for the shop to build the bottom end for me?
thanks
brady

 

Bore it if it needs it, and any other cleanup work. 350 HP is well within the range of stock blocks, no special prep of any kind has to be done for that mild of a buildup.

You might want to drill a tiny (~ .016-.020", about a #65 wire gauge drill) hole in each of the 2 oil gallery plugs to the sides of the cam bore, NOT THE ONE ABOVE THE CAM BORE, before they are put in. This will oil the timing chain.

Block prep with boring should be in the $200ish range, probably another $250 to asemble it. I would strongly recommend using a racing shop, not Joe's Garage (unless of course, Joe just happens to be one of the circle-track guys in your area that wins alot). You want a specialist, not a slap-it-together-on-the-low-bid, mass-produced, bargain special.

 

thanks
basically this is the deal i am getting a free 350 4bolt with 2 piece rear main seal the engine comes with the block, crank, rods, pistons, and heads. the engine was burning oil before it was taken out and i would want to rebuild it before it goes into my car, does anything need to be done to the crank, or rods?

 

if your going poor man with just reusing all the stock stuff then corners can be cut, but if your going with new pistons and what not your going to need the rods resized, arp bolts installed, pistons pressed on, crank turned (if need be, usally allways) block bored and honed, block decked, R&R freeze plugs and cam bearings, and balance, this will run you in the 800$ range to do it right and have a reliable 100,000 mile plus engine, you can cut corners but the engine life and power will be cut short

 

so it would probably be easier and cheaper to just buy the a crate engine?

 

No.

A quality rebuilt short block engine, along stock lines, will be much cheaper than most crate engines. Probably around $800 in the US. Supply them with the cam of your choice, as well as the heads and intake, if you have them install the engine. 350 hp should not be very hard.

 

where do i look for a shortblock like that?

 

it's hard to know what you need without measureing the holes. the pins, and mains. a lot of people blindly bore a block over size and grind a crank undersize, i wouldn't unless i know it needed it. then again i do all my own measureing and how many people have the tools to measure a block with. if i sent a block to a machine shop i'd have it cleaned, bored, decked. for higher HP i'd have it aligned honed as well. i always change rod bolts to ARP and if you're getting new pistons the shop will resize the rodsif they need it. i alos like to grind all the burrs and casting flash off the block, plug the oil drain holes in the lifter valley, glue screens in the big oil drain holes. it's debateable how much some of this is but it's cheap to do and takes more time than money.

 

Ede had a lot of good recommendations in his post to this topic. One other thing you ought to consider while you're getting the machine work done is getting the whole rotating assembly balanced(i.e. crank, rods, pistons, balancer, and flywheel). This makes life much easier for all the moving parts in motor putting out a healthy amount of horsepower. The shop that did mine charged me $175 for the balancing.

 

i agree having everything done is the way to go, but you can cut corners for a budget rebuild. hot tank, magnaflux, and a bore (if needed, they usually reccomend it if it does) are usual, plan on $150-300 for this. you can get away with a lot but see what you need. have them check the crank and see if that needs to be ground also if your reusing it. balancing is a good idea but not necessary (usually the only factory motors that were balanced were the police motors as far as i know) i've seen "standard commercial rebuilds" that just clean the block, hone it and assemble everything right there (after taking all the necessary measurements) . usually these motors last the life of the car .