Block Out to the Machine Shop

[timsweet]

Finally got the 351C dropped off at the machine shop.

It felt like I left the soul of the car across town.

Anyway I had them do some measurements for me so I knew from what point I was starting from.

1. Not sure the crank is going to be able to be turned, it was that bad. It was at .10 where it wasn't horribly worn.

2. The cylinders are at .030 and I'm going to have to go .040

3. Cam should be replaced.

4. They are going to check the deck and I may have them shave a bit off...but I don't want too much compression.

I'm going to wait until they've double checked the measurements and what the final verdict is on the crank is before deciding what I want to do with it.

But let's just say that I have to go .040 with on this 1972 351C block - that should be fine, I think.

Like to hear some of your opinions on a .040 build out.

Thanks

 

[Mister 4x4]

Well, I've mentioned many times the particulars of my build (click the "My Garage" button below for more details).

Mine would've originally been good-to-go with .020," except that it sat so long with the pistons rusted in-place - when I finally got the pistons out, the two worst cylinders required boring out to .060" just to get through the rust penetration 'scars' into the cylinder walls. My crank also needed .010"/.010" as well to clean it up.

Having said all that, I would've still gone with the same recipe, regardless of if the bore-specs were .020", .030", or .040".

I think yours will be awesome no matter what goodies you come up with. ::thumb::

 

[timsweet]

Hi Eric,

I've looked at your specs but I missed the .060 bore...that's got to be close to the max for this block? Maybe I've heard of .070 in some discussion.

My Crank is at .010 now and I'm not sure how much you can take off and I'm not sure I want them to build up. The shop will get back to me on my options there.

I have Performer LB 351-2V Made for 2 Barrel Heads w/Square 4 Barrel Flange coming...shipped today.

I do have to choose pistons and CAM next. I going to stick with the stock lifters since I've just replaced them all. Thoughts?

I had hooker headers on my 1970 - 302...those were great...the exhaust is new on the 73 so I have to think about that...but it can come later as well.

Well, I've mentioned many times the particulars of my build (click the "My Garage" button below for more details).

Mine would've originally been good-to-go with .020," except that it sat so long with the pistons rusted in-place - when I finally got the pistons out, the two worst cylinders required boring out to .060" just to get through the rust penetration 'scars' into the cylinder walls. My crank also needed .010"/.010" as well to clean it up.

Having said all that, I would've still gone with the same recipe, regardless of if the bore-specs were .020", .030", or .040".

I think yours will be awesome no matter what goodies you come up with. ::thumb::

 

[clevelandcoupe]

Tim,

I have had many Cleveland motors built and my builder states that due to the thin cylinder walls, no cylinders should be bored anymore than 30 over, period.... There has been many conversations on this great forum about this issue and for most people who intend on drive alot or possibly race these engines this should be the standard, unless you're a gambling man... and this is according to a builder of more clevelands than most, in my opinion.

Thanks, Jay

 

[Don C]

If they are flat tappets I would replace them. They are broken in and work hardened to your existing cam. I wouldn't want to take a chance on wiping out the new cam.

 

[Carolina_Mountain_Mustangs]

Tim,

A lot on the overbore depends on core shift when the block was cast. Also how much has rusted away. A good shop will have a sonic wall thickness checker to verify how thick it actually is. Racers use to sort through engines checking the wall thickness to find one that was near perfect. The ford cranks have way oversize bearing diameters. That is one fault that holds them back from high RPMs. Grinding the crank further would not concern me at all. It is not going to be weak over .010 - .020" in dia. change. I would not let them weld the crank and grind. Welding is ok if there is no other solution but requires someone that knows their stuff and not one of the spray welders they are so hit and miss. All the cranks are the same so there should be lots available.

Do have them check the diameters of the lifter holes. That is where lots of oil is lost on some engines starving bearings. We use to hone them to a specific size and have the lifters made to fit but don't have that connection today. You could have the lifters hard chromed or electrolytes nickel plated and centerless ground if you know of a shop so equipped.

Hey they use to build these engines in the 70's for NASCAR and run them wide open for 500 miles. As long as you have a good cooling system and don't go too wild on the cam you should not have heating issues.

We use to bore flathead Ford engines 3/16" over or more for racing. That was before thin wall castings came to be.

 

[timsweet]

Don,

They are flat tappet, but they are only a few months old and I discovered the knock after driving only about 40 miles total and then parted the Stang until I had time to pull the Cleveland.

Tim

If they are flat tappets I would replace them. They are broken in and work hardened to your existing cam. I wouldn't want to take a chance on wiping out the new cam.

 

[timsweet]

Thanks David.

Where do I find the dia. of the lifter holes?

Tim,

A lot on the overbore depends on core shift when the block was cast. Also how much has rusted away. A good shop will have a sonic wall thickness checker to verify how thick it actually is. Racers use to sort through engines checking the wall thickness to find one that was near perfect. The ford cranks have way oversize bearing diameters. That is one fault that holds them back from high RPMs. Grinding the crank further would not concern me at all. It is not going to be weak over .010 - .020" in dia. change. I would not let them weld the crank and grind. Welding is ok if there is no other solution but requires someone that knows their stuff and not one of the spray welders they are so hit and miss. All the cranks are the same so there should be lots available.

Do have them check the diameters of the lifter holes. That is where lots of oil is lost on some engines starving bearings. We use to hone them to a specific size and have the lifters made to fit but don't have that connection today. You could have the lifters hard chromed or electrolytes nickel plated and centerless ground if you know of a shop so equipped.

Hey they use to build these engines in the 70's for NASCAR and run them wide open for 500 miles. As long as you have a good cooling system and don't go too wild on the cam you should not have heating issues.

We use to bore flathead Ford engines 3/16" over or more for racing. That was before thin wall castings came to be.