balancing a 351

Reply Subscribe

Thread Tools

Search this Thread

Jul 9, 2008 | 06:55 AM

z1121jack

Thread Starter

Senior User

Joined: Feb 2008

Posts: 176

Likes: 0

balancing a 351

I'll soon be overhauling the 351w for my street rod. This is my first experience with a performance engine so t need some help.
My questions for the moment relate to engine balancing:
How do I find a good shop for engine balancing?
What exactly should I expect the balancing shop to do?
Do I take the engine block to the shop partially assembled?
What is the probable cost for engine balancing?
What other things do I need to know that i8 am to inexperience to ask?

Jul 9, 2008 | 07:36 AM

BaronVonAutomatc

Postmaster

Joined: Mar 2005

Posts: 2,949

Likes: 6

From: Earth

Depending on what else you're going to have done to the engine, the shop will balance the crank, damper, and flexplate/flywheel using jigs to simulate the weight of the pistons/rods. They'll spin the crank/balancer/flexplate on what looks kind of like a tire balancing machine, then drill the crank and add slugs in the throws, and spin again to confirm the balance. Most any reputable machine shop can do a balance job. Usually runs ~$175.

Jul 9, 2008 | 09:29 AM

z1121jack

Thread Starter

Senior User

Joined: Feb 2008

Posts: 176

Likes: 0

thanks Baron

Jul 12, 2008 | 06:31 PM

doug1222556

Posting Guru

Joined: Mar 2007

Posts: 1,649

Likes: 2

The first thing you want to do is have the block looked at. You can take the other parts with you and have them looked over ,too. If the block needs to be bored oversize, then new pistons of that size will have to be purchased- so there is no point in balancing the assembly with the old ones or a size you think you need,but wind up needing different. They don't need the block for balancing, but they need all the parts you intend on using as BVA stated. Word of mouth is the best way to find a good machine shop. Ask people who have street rods, small shop mechanics and racers at the local drag strip. BTW- where are you located? You may be close enough to use one near me or BVA.

Jul 12, 2008 | 08:09 PM

Dave Severson

Posting Guru

Joined: Nov 2005

Posts: 1,302

Likes: 0

From: Madison, SD

You will also need the pistons, pins, rings, rods, and rod bearings you will be running, along with the crank, flywheel, and balancer. They all go into determining the correct bob weight to balance the crank with. Balancing should be in the neighborhood of $200-$300. Internal balancing is a bit more expensive then external balancing. Internal balance can also get real spendy if much mallory metal is required for the crank weight.

Jul 13, 2008 | 07:12 AM

z1121jack

Thread Starter

Senior User

Joined: Feb 2008

Posts: 176

Likes: 0

thanks for the comments. Iive about 60 miles east of Houston,Texas.

Jul 13, 2008 | 10:50 AM

BaronVonAutomatc

Postmaster

Joined: Mar 2005

Posts: 2,949

Likes: 6

From: Earth

Oh, there should be plenty of good machine shops around you then. Call around to a few local speed shops and they'll be able to steer you in the right direction.