emccomas

What do you think about this engine pad....

razman

nope......

Mike Ward

I like.

emccomas

Mike;

I assume you are thinking what I am thinking...factory regrind.

The original suffix code of LA (427 / 390 hp in a passenger car) is clearly visible. Changed to a suffix code of LM (427 / 390 hp in a Corvette).This is a late production (Dec of 1969, build date Q03) car that was banged up about 30 years ago.

It has been in dry storage since then.

I think that the changes between LA and LM were intake manifold, exhaust manifolds, carburetor, distributor.

There seem to be an inordinate number of 69 engine pad "corrections", relative to other years.

Yet another mystery.

bkvette3

Mike Ward

Yup, factory regrind. Al G has all sorts of info on these. I'll take this engine over one of the 'pretty ones' any day.

bkvette3

OK - school me on this one - I am not familiar with factory regrinds. How does one determine a factory regrind??? Thanks BK3

emccomas

I recently re-read Al Grenning's articles on grind outs to refresh my memory. This "grind out" seems consistant with those.

This engine will be questioned the rest of its life, but I think it is explainable.

emccomas

Al Grenning and MIke Antonick both wrote articles for The Restorer (NCRS publication) about engine pad grind outs.

"Factory Engine Pad Regrinds", M. Antonick, Winter 1996 issue
"Real Life 1963-1967 Engine Pads", A. Grenning, Spring 1995
"Looking at Engine Pads from a New Angle", A. Grenning, Fall 1994.

Alan 71

Hi bkv,
In my mind the 'uglier' the grind out is, the more likely it is that it was done at during production.
They did some real BEAUTIES!
Regards,
Alan

bkvette3

Thanks - will research the above. Is there archived articles on the NCRS site??? Would love to read these articles and learn.

Easy Mike

You can get a boatload of Restorer articles on CD. They are always listed in The Driveline.

Mike Ward

Much like original broach marks running fore-aft on a block (which are very very difficult to reproduce accurately), factory grind outs mostly have a typical look to them, one characteristic being just how sloppy they were as Alan noted.

They were, like this one, most commonly done before the engine was installed in the car so only the engine code was ground out and restamped and not the VIN.

Although a counterfeiter could possibly grind out and restamp a low HP Corvette engine and make it into a high HP version and maybe get away with it, in this case the engine was originally destined for a different car line. It was ground out and stamped before it left Tonawanda.

bkvette3

Cool topic - Gentlemen, thanks for the lesson. (I am getting smarter every day. ) BK3

Alan 71

Hi,
Not to steal this thread but....
Here's the transmission stamp on my 71.
The code looks fine, but obviously they screwed up the VIN derived stamp. Nice job Xing it out!
It appears they got it right the second time.
Regards,
Alan
'P' Muncie, '1' Model year (not year of production), 'T' December, '21' Day, 'A' Wide Range. Mid January 71 built car.

BKarol

FYI
I tried to find a Restorer article written by Gene Gamache about "M codes" so that I could read it (I am a member)

Emailed the ncrs web people after my search and they said the archived articles can not be read but if I know the year, I would need to buy the cd $50.

Perhaps someone can make a copy of the article you need.

Alan 71

Hi bkv,
I have those RESTORER issues.
I'll make copies of the articles and mail them to you. (That'll be easier/quicker for me than scanning them.)
Send me a pm with your address, and I'll do it this week.
Regards,
Alan

razman

that makes two of us Blair! very interesting info that i was totally unaware of, this is a GREAT hobby huh? Rick

emccomas

Factory grind outs are rare, but not as rare as some people think. And there is a "pattern" to them that is recognizable once you start looking at them.

And it is almost always a "judgement call".

Alan 71

Hi emc,
Your right about the 'patterns'
They're what makes Al G's presentations so interesting... he shows you a pad that you say NO WAY!.... and then he shows you the next one or two in sequence.... and they're just as ugly!
Regards,
Alan