Machining my Block
Thread Starter
Member
Joined: Feb 2009
Posts: 37
Likes: 1
From: Montana
Machining my Block
How can you tell if you need to bore your block out vs. honing it? What else should I look or ask for when I take my block to get machined, the real critical Must haves? like rebuilding the head, getting my crank turned ect??
Senior Member
Joined: Feb 2008
Posts: 4,658
Likes: 28
From: Henderson, NV.
Select a dependable machine shop that comes well recommended and trust them. Manuals show using telescopic T-gauges and a micrometer to measure out of round and taper, thats older technology than I am. Machining is best left for them and go by their recommendations.
GLOBAL WARMER
Joined: Dec 2008
Posts: 62
Likes: 0
From: Gilbetown, Alabama
Knowing if a block need boring comes down to a few factors, overall bore size, piston to cylinder clearance, ring-end gap, bore out-of-round, and scarring. I think there is some more but those are some of the bigones.
I agree with GOB, you have to trust the machinists recomendations. But make sure HE is RECOMMENDED! Know before you go, the basic way you want to take the build Street, towing, street/strip, All out race.
Most likely he will recommend a bore job unless you piston require a finish bore slightly larger than your existing bore, you may get lucky. He won't finish hone the block untill you get pistons (different pistons require different clearances). You will pay more for torque honing, if you not building a race engine you really dont need this step.
The crank may not need turning sometimes they can just be polished and they can just need a over sized bearing (0.001-0.003) instead of a full turning.
If you plan on changing rod bolts he will probably resize the rods with the new bolts. Also if you use pressed-style pistons and rods they have to be assembled.
Tell him if you plan on running a roller cam, sometimes the blocks need special attention in areas. Like our machinist prepped our chevy block for a double roller timing chain even though he didn't know we were going to run one and some he did some other small things just because it how he does it.
Be prepared to pay for good work. A good machinist is going to recommend what he thinks is needed and offer you options. Remember this his lively hood rest on his reputation.
Make a list of your questions.
No customers, No Cash.
I know this does not cover everything, but I hope it helped.
I agree with GOB, you have to trust the machinists recomendations. But make sure HE is RECOMMENDED! Know before you go, the basic way you want to take the build Street, towing, street/strip, All out race.
Most likely he will recommend a bore job unless you piston require a finish bore slightly larger than your existing bore, you may get lucky. He won't finish hone the block untill you get pistons (different pistons require different clearances). You will pay more for torque honing, if you not building a race engine you really dont need this step.
The crank may not need turning sometimes they can just be polished and they can just need a over sized bearing (0.001-0.003) instead of a full turning.
If you plan on changing rod bolts he will probably resize the rods with the new bolts. Also if you use pressed-style pistons and rods they have to be assembled.
Tell him if you plan on running a roller cam, sometimes the blocks need special attention in areas. Like our machinist prepped our chevy block for a double roller timing chain even though he didn't know we were going to run one and some he did some other small things just because it how he does it.
Be prepared to pay for good work. A good machinist is going to recommend what he thinks is needed and offer you options. Remember this his lively hood rest on his reputation.
Make a list of your questions.
No customers, No Cash.
I know this does not cover everything, but I hope it helped.