I built a couple 392 Hemi's a few years ago and had the blocks shot blasted and they came out looking like new, the factory number stamps remained unaffected.
The lifter valley looks a little shiny as it was slightly smoothed before blasting.

Rick..Im getting ready to send off a batch to be thermal cleaned..i will take before and after pics for ya...

i have some 2.02 69 heads etc...it will not remove pitting, but it will not touch striations and extrusion marks...i have some steel and some alum going tomorrow...i will get some pics..it takes my guy a week..but i am never in a real hurry..he has an ampro system like your pics...i use it on everything like clutch pedals, brackets, pullies..i have a good asst going in..so it will give a good idea

the whole secret is new media...it makes a diff..a big diff..he called me last week and said he changed the media...so its really nice on alum..i run the separate...alum first then steel..

if you have really rusty steel..the alum will have a brown haze...if you do the steel first

i want to do a steel wheel this time...ive wanted to for some time..and am running one thru..i have concerns because it will burn the paint out of the joints..i wonder what that wull do..i want to experiment on a couple..im afraid rust will bleed out of the cracks etc...

I have a block (bbc) that has had the lifter valley that appears to have been shot peened. I can only assume it was to aid in oil drain back? The texture is smoother than the rest of the cast surfaces. If it had not been for my penchant to test fit everything before assembly, I would not have caught that the peening had distorted the tops of each lifter hole preventing lifter installing. Deburring corrected this. But be aware that distortions are possible.
On another bb I have that was rusty, the shop put it in a blast cabinet with a caustic soda rinse. Now, you have to use a magnifying glass to read the pad. Guess the shop screwed that one up? So, be careful. I like the magnet idea On the pad mentioned

I would by a 55 gallon drum of safest rust remover and drop it in.

I was going to suggest evaporust. I think it is comparable to safest. Might be expensive, but it does a great job of removing rust and leaving everything else.

Rick, In another thread you, I and others were discussing cleaning parts in general.

Ive had all kinds of the other chassis parts, eng brkts etc etc....run through a local
shot blasting machine. What with all the massive shop time you charge customers
to stand in front of your slow glass beading machine, you need to take most of your other steel parts to the shot blaster assuming the cost is acceptable.
My shot blast guy also has a enclosed basket that I place fasteners into and then
shot blast. Ready to replate or you could quickly run thru your glass beader


Ive also bought a used MrDeBur shaker/vibrator which is another option to clean
restore metal finishes.

Chuck, glad to see you have analyzed how I run my business and seem to know how and what I charge our customers.

I currently use several forms of blasting for our customers; plastic, aluminum oxide, sand and shot. However, we normally do these in large quantities to keep the costs down low not to mention the drive time, fuel and labor costs to deliver and pick up. The glass beading cabinet is used primarily for small trinket parts and ones that will be dipped in paint as I do not want them to be etched. Also when we need to have something blasted immediately and cannot wait to take them to the commercial blaster.

I get your point though about wasting peoples time and money. Had it done to me a time or two.....

Just as effective and cost a LOT less is white vinegar. I can get a gallon at the dollar store for a buck. I would think a 55 gal. drum could be bought through Costco, GFS, Aldi, Sams?

I actually bought a tub, sprayer, hose and several gallons of Evapo-Rust (which I use lots of anyway) and just decided this block was just too crusty to go that route when for considerably less time and money I could have it shot blasted. I use Evapo-Rust on brake pedal assemblies, e-brake assemblies and many other components that were bare steel when assembled and it works quite well.

Rick....You had earlier stated " We spend hours a day at the glass bead cabinet for things like spindles, steering arms, brackets, clips, etc and it is a complete waste of time when I could be having a machine do it automatically for me while we do something more constructive. The expense does not really bother me as that could be paid for in less than a week in saved production time alone."

I certainly didnt mean to imply you were overcharging anybody. I was suggesting that shot blasting and vibratory tumbling/shaking would cut down on your labor hours and increase your shop productivity.

My best regards,
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