63 427 block sonic test

[67xr7cat]

So I've been told the early 427 blocks had thicker cylinder walls.  Recently I had a chance to use my ebay special $100 sonic tester.  Have to say once found the right coupling fluid (used dielectric grease) and got used to how to use it I could get very good and repeatable reading.  I used the china wall as a check both before and after sonic testing the block. Was impressed it read the china wall within .001" of what I measured its thickness as being. 

So this is a an early 1963 427 block C3AE-6015-AB and is currently standard bore. Other than some core shift on cylinder 7 I was surprised at how overall thick this block was. I know a sample of one cannot draw any conclusion as to how the rest are, but I'd say this one at least did not disprove the theory that the early 427 blocks are thick. Anyway sonic sheet is attached. Steve

[galaxiex]

Wow, if accurate that looks pretty good!

[67xr7cat]

Well I can say I view a sonic tester as only as good as the operator.  I can say in some areas I could mechanically measure the thickness and did as a check.  I can say are spots where you could only get a .040" feeler gauge between the bores.  I am amazed that in 1963 Ford could cast a block that well.  Compared to a 390 the 390 looks to have the wide open spaces between the bores.  I've been told that Ford had used special fixturing on these blocks.  Don't know if it is true, but they certainly held a close tolerance between cylinders from what I can see. Steve

[WConley]

Ray Paquet used to say that the early 427 blocks had the best cylinder walls.  He always used center oilers to build the engines for his SS/A T-Bolt.  He sonic'd dozens of blocks before selecting the best few for his "stash"...

That was 25 years ago now, not sure if he's still running factory blocks.

[GJCAT427]

 What make tester are you using?

[pbf777]

     For calibrating ones' sonic tester you want to use:  a like material, that is of a similar thickness to that which is being tested, and of similar shape.  With this in mind, I cut sections of the cylinder wall out of junk blocks and use this to calibrate before each use.  Note that I consider Fe's and S.B.F.'s to be of similar metal, but for example 385 series engines seem to be of harder, cleaner cast material, and many race blocks to be quite different material.   

     Scott.

[XR7]

Ray Paquet used to say that the early 427 blocks had the best cylinder walls.  He always used center oilers to build the engines for his SS/A T-Bolt.  He sonic'd dozens of blocks before selecting the best few for his "stash"...

That was 25 years ago now, not sure if he's still running factory blocks.

I know for sure at least on one engine, Ray was using a Pond iron block, they are really strong.

I have a center oiler block, it was cast in November of 64, it had major thrusts all over 200. It also had the "clover leaf" or bulged four corners that are even thicker. It was a C5 block with 4 bolt engine mounts and had an XE 1 sand scratch on the back. 

[67xr7cat]

What make tester are you using?

The one I have is same as the one in post 2 of this thread:

http://fepower.net/simplemachinesforum/index.php?topic=5449.0;all

[GTwayne]

     For calibrating ones' sonic tester you want to use:  a like material, that is of a similar thickness to that which is being tested, and of similar shape.  With this in mind, I cut sections of the cylinder wall out of junk blocks and use this to calibrate before each use.  Note that I consider Fe's and S.B.F.'s to be of similar metal, but for example 385 series engines seem to be of harder, cleaner cast material, and many race blocks to be quite different material.   

     Scott.

Great News on the Block. I have an early center oiler that has a thin spot. Lower than the ring land so its alright.
Getting bake to the thickness checker, at an unNamed Aerospace company I worked for I had a crew of inspectors that used a thickness checker to measure skin thicknesses for Engineering repairs. One of the first thing is to validate a known thickness OF THE SAME MATERIAL. AKA 2024 T3 Aluminum, 6061 T6 etc. Straight at the thickness to be measured. (you can make it thicker if you angle it)
That said, now at least you know what ya got.

[Joe-JDC]

Does your sonic test head have an arc on it? IF not, then you are about .050" high on all your readings.  The head must have an arc to fit close to the cylinder roundness to read properly.  Joe-JDC

[67xr7cat]

Does your sonic test head have an arc on it? IF not, then you are about .050" high on all your readings.  The head must have an arc to fit close to the cylinder roundness to read properly.  Joe-JDC

Yes it does. First thing I did when I got it was sand on the transducer until it fit the cylinder curve. Have say that took some time to get right.

[67xr7cat]

     For calibrating ones' sonic tester you want to use:  a like material, that is of a similar thickness to that which is being tested, and of similar shape.  With this in mind, I cut sections of the cylinder wall out of junk blocks and use this to calibrate before each use.  Note that I consider Fe's and S.B.F.'s to be of similar metal, but for example 385 series engines seem to be of harder, cleaner cast material, and many race blocks to be quite different material.   

     Scott.

Great News on the Block. I have an early center oiler that has a thin spot. Lower than the ring land so its alright.
Getting bake to the thickness checker, at an unNamed Aerospace company I worked for I had a crew of inspectors that used a thickness checker to measure skin thicknesses for Engineering repairs. One of the first thing is to validate a known thickness OF THE SAME MATERIAL. AKA 2024 T3 Aluminum, 6061 T6 etc. Straight at the thickness to be measured. (you can make it thicker if you angle it)
That said, now at least you know what ya got.

Yes am a bit surprised on the block. Only thin spot really is at bottom side of 7.  I've always been suspect of sonic tester readings, but this one works well. The coupling fluid that came with it did not work well and you have to be a bit firm and hold the transducer correctly to get good reading, but is fairly easy to know when it is not right.

[pbf777]

The coupling fluid that came with it did not work well and you have to be a bit firm and hold the transducer correctly to get good reading, but is fairly easy to know when it is not right.

     Yes, as with many things, it takes proper technique to acquire the accurate result.     

     Scott.

[Joe-JDC]

I have found the white lithium grease to work very well on cylinder walls.  Some time you might need to run a ball hone through the cylinders to break any rust free, and wipe down with WD-40, but the lithium works really well after that.  Wear a latex type glove if you use it.   Joe-JDC

[67xr7cat]

I have found the white lithium grease to work very well on cylinder walls.  Some time you might need to run a ball hone through the cylinders to break any rust free, and wipe down with WD-40, but the lithium works really well after that.  Wear a latex type glove if you use it.   Joe-JDC

All good points.  It has been about 18 years since I sonic tested a block. Back then was white grease that we used.  I had bought a tub of it for this and when I went to test this block could not find it. Is frustrating when cannot find stuff.  So tried the dielectric grease which have to say worked great. Just a bit harder to remove afterwards.  I used a rigid hone on this one as was handy and also to give an idea what parts of the cylinder are low as well as get a clean surface to sonic. Is some wear at the top of some of the cylinders in this block for sure.  Also found some damage to cylinder one looks like a piston got jammed and is cracked.  When I get my magnafluxer together will check it, but looks like will need a sleeve.  Could not see this until honed the cylinder. Thanks, Steve