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1969 The motor is numbers matching to the VIN (Vin=194379s710637) but why is there an "I" in the date code? The HX should be 350 L46 Rochester Q-jet spec. cam, A/C, and 4 speed. Is that "i" a one in number? V-Flint engine then !204HX = VI204HX
I was used in place of 1 to varying degrees. I believe that date would be December 4th.
Your block has been decked - or at least aggressively sanded - and the engine stamp has been tampered with in some way. The factory did make mistakes and regrind these stampings at times but I'm not certain your block shows typical factory grind-out.
I was used in place of 1 to varying degrees. I believe that date would be December 4th.
Your block has been decked - or at least aggressively sanded - and the engine stamp has been tampered with in some way. The factory did make mistakes and regrind these stampings at times but I'm not certain your block shows typical factory grind-out.
I scraped and light sanded with paint removed because the paint was think and did not reveal the numbers. Do you think it's not numbers matching?
I scraped and light sanded with paint removed because the paint was think and did not reveal the numbers. Do you think it's not numbers matching?
The pad surface does not look factory. To be honest you may have bungled the pad by sanding it. Big no-no. Outside of that the numbers and date look good to me.
The pad surface does not look factory. To be honest you may have bungled the pad by sanding it. Big no-no. Outside of that the numbers and date look good to me.
That first pic does not really show what it looks like (super close up in magnify camera mode) here is more what it looks like to the eye.
I really don't know. The VIN stamp appears untouched, so I'm not really questioning whether the block came with the car. I believe you can see straight factory broaching marks above the VI204 so maybe it wasn't ever decked and merely aggressively sanded at some point. Your light sanding and scraping isn't going to create those circular scratches - the head had to have been off to do those. The engine code stamp is definitely non-typical for engines that were not altered at the factory. You can tell that portion of the pad has been abraded differently than the rest of the pad. I'm not at all familiar with how a grind-out and restamp at the factory typically appears.
While everything looks ok from a numbers and date perspective that pad looks like it was tampered with at some point. Could it be a factory grind out, maybe but I would want an expert on the subject to tell me that.
Because these L-46 engines were stamped with different codes depending on trans and A/C, it could be that this engine was originally stamped for some other configuration than the HX (i.e., HW, HY, HZ) and on the assembly line was ground out and restamped to reflect your car's options. This would have been done at the same time as the VIN stamp. But I'll let others who are more familiar with this type of situation step in.
Because these L-46 engines were stamped with different codes depending on trans and A/C, it could be that this engine was originally stamped for some other configuration than the HX (i.e., HW, HY, HZ) and on the assembly line was ground out and restamped to reflect your car's options. This would have been done at the same time as the VIN stamp. But I'll let others who are more familiar with this type of situation step in.
The HX code is exactly correct for what the car is option wise.
Last edited by 2HD's2vettes; Mar 20, 2022 at 02:59 PM.
i think that is an OE grind-out and re-stamp. they did not care about pretty. and could not have cared a little bit about NCRS juidges in 45 years. all they cared was it was the correct date and code and vin....
i think that is an OE grind-out and re-stamp. they did not care about pretty. and could not have cared a little bit about NCRS juidges in 45 years. all they cared was it was the correct date and code and vin....
That seems to make the most sense. The sanding I did was very fine grit, and light bristle wire brush after some paint remover, can't see how that could do much to a hardened steel block pad? The numbers were filled with orange paint/repaint and were not readable prior to cleaning that pad area up.
Last edited by 2HD's2vettes; Mar 20, 2022 at 05:45 PM.
Because these L-46 engines were stamped with different codes depending on trans and A/C, it could be that this engine was originally stamped for some other configuration than the HX (i.e., HW, HY, HZ) and on the assembly line was ground out and restamped to reflect your car's options. This would have been done at the same time as the VIN stamp. But I'll let others who are more familiar with this type of situation step in.
The grind out would have been done at Flint, the vin stamp at St. Louis.
That seems to make the most sense. The sanding I did was very fine grit, and light bristle wire brush after some paint remover, can't see how that could do much to a hardened steel block pad? The numbers were filled with orange paint/repaint and were not readable prior to cleaning that pad area up.
The pad is not hardened steel, but regular old cast iron. It's scratch-able with just a screwdriver or razor blade. Someone prior to you (and not an assembly line worker) used a sander/grinder on the pad to create the directionaly non-uniform large diameter swirls separate from the grinder marks of the engine code. Factory finish on the pad is a series of relatively fine straight lines running from front to back. These lines were created by a broaching machine that flattened the cylinder deck when it was first machined after casting and prior to assembly. I mentioned they may be evident above the V1204 characters.
Originally Posted by 62corvette
The grind out would have been done at Flint, the vin stamp at St. Louis.
How would Flint have known that an engine would need to be swapped into a chassis not coinciding with the stamp and thus requiring a grind-out? Seems as though that would be a St. Louis fix.
How would Flint have known that an engine would need to be swapped into a chassis not coinciding with the stamp and thus requiring a grind-out? Seems as though that would be a St. Louis fix.
All engines were stamped at Flint and a grind out would have happened at Flint, St. Louis only stamped the VIN number on the engine pad. Flint built over 5000 engines a day in a verity of configurations and had gang stamps setup for each of those configurations at the start of the day. A grind out was most likely due to the assembly line worker grabbing the wrong gang stamp and having to restamp it.
I too believe it to be a factory grind out. As stated there were a number of different L46 engine configurations, with both TI & AC, with TI, With AC, and without either. The build date appears to have been the same prior to the grind...
Minor differences in configuration which could be easily altered if the required engine was not on hand.
If not mistaken the engine date - and VIN number point to late december early jan build, for which the holidays could have kinked the supply chain.
Not sure this has been mentioned, but front sway bar with a 427 in '66 should be 7/8" diameter unless it's got the F41 option, which would then be 15/16". Your rear spring pack would also be different with the F41, so there is a correlation there.
Your '66 would not have a tank sticker, that started in '67.
Bottom line is paperwork or an original block stamp is the only way to prove the L72 option in '66. Everything else can be changed or added. If your car hasn't been restored, and shows typical patina throughout, it's much easier to verify, but when things are cleaned, painted, upgraded, or altered, all bets are off.
All this will effect value, then the car will be valued on it's presentation, not necessarily it's pedigree.
Not sure this has been mentioned, but front sway bar with a 427 in '66 should be 7/8" diameter unless it's got the F41 option, which would then be 15/16". Your rear spring pack would also be different with the F41, so there is a correlation there.
Your '66 would not have a tank sticker, that started in '67.
Bottom line is paperwork or an original block stamp is the only way to prove the L72 option in '66. Everything else can be changed or added. If your car hasn't been restored, and shows typical patina throughout, it's much easier to verify, but when things are cleaned, painted, upgraded, or altered, all bets are off.
All this will effect value, then the car will be valued on it's presentation, not necessarily it's pedigree.
Not sure this has been mentioned, but front sway bar with a 427 in '66 should be 7/8" diameter unless it's got the F41 option, which would then be 15/16". Your rear spring pack would also be different with the F41, so there is a correlation there.
Your '66 would not have a tank sticker, that started in '67.
Bottom line is paperwork or an original block stamp is the only way to prove the L72 option in '66. Everything else can be changed or added. If your car hasn't been restored, and shows typical patina throughout, it's much easier to verify, but when things are cleaned, painted, upgraded, or altered, all bets are off.
All this will effect value, then the car will be valued on it's presentation, not necessarily it's pedigree.
Engine pad numbers - asembly date question??
