1963 Corvette High Performance Oil Pan..Clearification Needed

[Richard S.]

The 63 Judging manual says there should be 2 dimpled 1 1/2 long depressions on each side of the high perfromance oil pan. The sump length for high performance is 13 1/2 inches long as opposed to a 10 1/2 for the non-high performance, thats clear however all the pans I see stating high performance have 3 dimples on one side and two on the other...is the 63 Forth Edition Judging manual incorect?

[Tracy C.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

we are at rev6 with the 63/4 jg.

[Edward J.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Rich, the new 6th ediion manual is correct. It still has the same description which is correct. the dimples are really more like depressions on each side of the pan.

[Richard S.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Thanks for the replt Ed but it is still not clear as the manual says 2 dimples on each side but the pans seem to have 3 on one side such as this one on ebay:

http://www.ebay.com/itm/1963-72-CORVETTE-327-350-NOS-GM-6-QUART-TRAP-DOOR-OIL-PAN-FUEL-INJECTION-LT1-/281534747706?pt=Motors_Car_Truck_Parts_Accessories&hash=item418cc7543a&vxp=mtr#ht_371wt_817

Is this one correct?

Rich, the new 6th ediion manual is correct. It still has the same description which is correct. the dimples are really more like depressions on each side of the pan.

[Joe L.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Thanks for the replt Ed but it is still not clear as the manual says 2 dimples on each side but the pans seem to have 3 on one side such as this one on ebay:

http://www.ebay.com/itm/1963-72-CORVETTE-327-350-NOS-GM-6-QUART-TRAP-DOOR-OIL-PAN-FUEL-INJECTION-LT1-/281534747706?pt=Motors_Car_Truck_Parts_Accessories&hash=item418cc7543a&vxp=mtr#ht_371wt_817

Is this one correct?

Richard-------


Not exactly (but it has nothing to do with the vertical impressions on both sides). The pan pictured is a GM #359942. This was a 1975 SERVICE replacement for the original pan, GM #3820001. The primary, if not only difference between the two pans is the radius of the front oil pan gasket surface. The original pan was 2-1/4" radius; the 359942 was 2-3/8". Otherwise, they are the same.

Attached are photos of an original GM #3820001 oil pan. The example pictured is a VERY old NOS pan, most likely manufactured in the 1963-65 period. I am extremely confident it's the same as those used in PRODUCTION during that period. Note that the pan has three vertical impressions on the driver side and 2 vertical impressions on the passenger side, the same as the 359942.


GM#3820001 001.jpgGM#3820001(a) 001.jpg

[Harry S.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Beat up but it may help.....

http://www.ebay.com/itm/1963-Corvette-Original-Oil-Pan-/251783597934?pt=Motors_Car_Truck_Parts_Accessories&hash=item3a9f78cf6e&vxp=mtr

[David L.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Pictured below is a NOS 3956670 oil pan.
As per Chevrolet & GM Parts History:
GM # 3820001 was replaced (service parts, not assembly line) in June 1970 with GM # 3956670 which was then replaced with GM # 359942 sometime in the mid to late 1970's.

Oil pans 3820001 and 3956670 both use the 0.22" thick front rubber gasket.
Oil pan 359942 used the 0.41" thick front rubber gasket.

I believe that oil pan 3956670 was redesigned to accomodate power steering but I am not 100% sure. Maybe someone else will know the actual difference.

Dave

[Joe L.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Pictured below is a NOS 3956670 oil pan.
As per Chevrolet & GM Parts History:
GM # 3820001 was replaced (service parts, not assembly line) in June 1970 with GM # 3956670 which was then replaced with GM # 359942 sometime in the mid to late 1970's.

Oil pans 3820001 and 3956670 both use the 0.22" thick front rubber gasket.
Oil pan 359942 used the 0.41" thick front rubber gasket.

I believe that oil pan 3956670 was redesigned to accomodate power steering but I am not 100% sure. Maybe someone else will know the actual difference.

Dave

Dave------


If that baffle was supplied with the pan, then I expect that the 3956670 was actually a unit involving a GM #3820001 oil pan + a GM #3927136 baffle (which is what the baffle pictured is). The strange thing is that I am unaware that baffle was ever intended for use with the 3820001 or 359942 oil pan. It was intended for use with the GM #3927134 (and supercessive part numbers) oil pan which is sometimes known as the "Z-28 Oil Pan". However, it was also used on 1975-79 Corvettes with L-82. The 3820001 and 359942 oil pans were designed for use with the GM #3769768 baffle which is essentially "flat".

In any event, the oil pan pictured, assuming it is some oil pan different from the 3820001, certainly does not appear to be modified from the 3820001 in any way which would accommodate power steering.

[David L.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Joe,

I found the photos of the oil pan on the net and the GM part # was stated as 3956670.

As far as I know a baffle was not included with a boxed GM oil pan purchased over the counter. The baffle in the photos does appear to be a 3927126 baffle used on 70 Z28 models as you mentioned. I have a NOS and a used 3927126 baffle in my collection.

I remember reading somewhere that the 3956670 oil pan was a redesign of the 3820001 oil pan so as to accommodate power steering in later models. I was hoping that someone who actually knew the difference would chime in.

I have a NORS 360010 oil pan and a gasket set, a 3951576 dipstick, and 3876870 dipstick tube were included in the GM box with instructions. The 360010 oil pan is a replacement for the 3974252 oil pan (used on 1970 Camaro SS350).

Dave

[Joe L.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Joe,

I found the photos of the oil pan on the net and the GM part # was stated as 3956670.

As far as I know a baffle was not included with a boxed GM oil pan purchased over the counter. The baffle in the photos does appear to be a 3927126 baffle used on 70 Z28 models as you mentioned. I have a NOS and a used 3927126 baffle in my collection.

I remember reading somewhere that the 3956670 oil pan was a redesign of the 3820001 oil pan so as to accommodate power steering in later models. I was hoping that someone who actually knew the difference would chime in.

I have a NORS 360010 oil pan and a gasket set, a 3951576 dipstick, and 3876870 dipstick tube were included in the GM box with instructions. The 360010 oil pan is a replacement for the 3974252 oil pan (used on 1970 Camaro SS350).

Dave

Dave------


A baffle was not included with the 3820001 or 359942. However, I don't know about the 3956670. I presumed that since the baffle is shown with the oil pan and box in the picture you posted, that the baffle was supplied with the pan although, as I mentioned, it's not the correct baffle for that pan.

The only way that the 3820001 oil pan could have been modified to accommodate power steering would be if the sump was either shortened or somehow re-configured on the front. However, neither appears to have been done to the pan pictured. In any event, no 1963-72 application using the 3820001 or 3956670 was ever equipped with power steering so there really would have been no need for GM to re-design the pan.

Some oil pans were supplied with an external baffle. The big block GM #14091356 is an example of one that is.

The GM #360010 oil pan was also used on all 1975-79 Corvettes with L-48. It was discontinued in February, 1979 and replaced by GM #465221 which was an oil pan + gasket set. Either pan is the same as the 3974252 except for the front oil pan gasket radius.

The "Z-28 Oil Pan" was originally known as GM #3916369. It was discontinued in February, 1968 and replaced by the GM #3927134. The latter was discontinued in February, 1969 and replaced by the GM #3961398. That pan was discontinued in October, 1969 and replaced by GM #3974251. GM #3974251 was discontinued in November, 1975 and replaced by GM #360009. The latter was discontinued in November, 1977 and replaced by GM #465220 which was an oil pan + gasket kit unit. Finally, GM #465220 was discontinued and replaced by GM #360450 which is an oil pan only with no gasket kit.

All of the above oil pans are "deep sump" and of virtually identical external configuration. The difference is that the "Z-28 Oil Pans" have sheet metal rails spot welded to the inner sides of the pans below the side gasket surface. These rails seat the sides of the 3927126 baffle.

The last iterations of the "Z-28 Oil Pans", GM #360009, GM #465220, and 360450, were also used on all 1975-79 Corvettes with L-82.

[David L.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Dave------


A baffle was not included with the 3820001 or 359942. However, I don't know about the 3956670. I presumed that since the baffle is shown with the oil pan and box in the picture you posted, that the baffle was supplied with the pan although, as I mentioned, it's not the correct baffle for that pan.

The only way that the 3820001 oil pan could have been modified to accommodate power steering would be if the sump was either shortened or somehow re-configured on the front. However, neither appears to have been done to the pan pictured. In any event, no 1963-72 application using the 3820001 or 3956670 was ever equipped with power steering so there really would have been no need for GM to re-design the pan.

Some oil pans were supplied with an external baffle. The big block GM #14091356 is an example of one that is.

The GM #360010 oil pan was also used on all 1975-79 Corvettes with L-48. It was discontinued in February, 1979 and replaced by GM #465221 which was an oil pan + gasket set. Either pan is the same as the 3974252 except for the front oil pan gasket radius.

The "Z-28 Oil Pan" was originally known as GM #3916369. It was discontinued in February, 1968 and replaced by the GM #3927134. The latter was discontinued in February, 1969 and replaced by the GM #3961398. That pan was discontinued in October, 1969 and replaced by GM #3974251. GM #3974251 was discontinued in November, 1975 and replaced by GM #360009. The latter was discontinued in November, 1977 and replaced by GM #465220 which was an oil pan + gasket kit unit. Finally, GM #465220 was discontinued and replaced by GM #360450 which is an oil pan only with no gasket kit.

All of the above oil pans are "deep sump" and of virtually identical external configuration. The difference is that the "Z-28 Oil Pans" have sheet metal rails spot welded to the inner sides of the pans below the side gasket surface. These rails seat the sides of the 3927126 baffle.

The last iterations of the "Z-28 Oil Pans", GM #360009, GM #465220, and 360450, were also used on all 1975-79 Corvettes with L-82.

Joe,

As I stated previously I do not believe that the baffle shown in the 2 photos above came with the NOS 3956670 oil pan.

I would like to know the actual difference between the 3820001 and 3956670. Both pans visually appear to be identical. Both use the thin front seal.

I have researched Chevrolet and Corvette oil pans for a few decades. Here are photos of Chevrolet oil pans showing the differences in the shapes.

1st photo (primered pan marked "3rd Pan"): 1967 (GM 3912396 or GM 3916369, Z28) or possibly a 1968 (GM 3927134 or 3937914, Z28) oil pan. However, I believe that it is a 1968 pan as I had a pan that looked exactly the same that was removed from a 1968 Chevrolet engine but sold it a few years ago.

2nd & 3rd photos:
1969 oil pan (pained red), GM 3961399 (same as GM 3961398 for Z28 except for the baffles inside)
1970-1974 oil pan (painted gray), GM 3974252 (same as GM 3974251for Z28 except for the baffles inside)

Dave

[Duke W.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

327s use a "flat" windage tray (baffle). The semicircular version was used on 350s, and I believe the reason the design was changed was to accommodate the 350's longer stroke. I'm not sure, but I think if you use the 327 windage tray in a 350 it will interfere with the rotating assembly.

Duke

[Joe L.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

Joe,

As I stated previously I do not believe that the baffle shown in the 2 photos above came with the NOS 3956670 oil pan.

I would like to know the actual difference between the 3820001 and 3956670. Both pans visually appear to be identical. Both use the thin front seal.

I have researched Chevrolet and Corvette oil pans for a few decades. Here are photos of Chevrolet oil pans showing the differences in the shapes.

1st photo (primered pan marked "3rd Pan"): 1967 (GM 3912396 or GM 3916369, Z28) or possibly a 1968 (GM 3927134 or 3937914, Z28) oil pan. However, I believe that it is a 1968 pan.

2nd & 3rd photos:
1969 oil pan (pained red), GM 3961399 (same as GM 3961398 for Z28 except for the baffles inside)
1970-1974 oil pan (painted gray), GM 3974252 (same as GM 3974251for Z28 except for the baffles inside)

Dave

Dave------


The baffle may not have been included with the 3956670 pan. However, if it was included, that would explain the reason for the part number change. Actually, it may be that the 3956670 pan had the INTERNAL baffle slightly lowered to accommodate the longer stroke of the 350 as Duke suggests AND included the 3927136 EXTERNAL baffle in order to be compatible with the new INTERNAL baffle when retrofit to 327 engines. This is exactly what happened with the GM GM #3977591 and GM#14091356 big block oil pans. The oil pan contained in the GM #3977591 pan UNIT was the first 454 oil pan. It had an INTERNAL baffle that was lowered compared to the earlier 396 and 427 oil pans. However, if this pan was used on 396 or 427 engines the 454 EXTERNAL baffle, GM #3967854, had to also be used. So, it was supplied with the pan for 65-69 SERVICE application.

Something boding against the 3956670 being supplied with a baffle is that GM did not describe it as a "PAN UNIT". Still, there remains the possibility that it was a "PAN UNIT".

[Joe L.]

Re: 1963 Corvette High Performance Oil Pan..Clearification Needed

327s use a "flat" windage tray (baffle). The semicircular version was used on 350s, and I believe the reason the design was changed was to accommodate the 350's longer stroke. I'm not sure, but I think if you use the 327 windage tray in a 350 it will interfere with the rotating assembly.

Duke

Duke------


That's very possible. However, GM catalogs the GM #3769768 (the flat baffle) as the baffle applicable to 1969 with 350 SHP (i.e. 1969 LT-1 of which none were ever released). This could have been an error, though. For 1970-74 with 350 and SHP (except HD 4 speed), they specify the GM #3989075. The latter is a "curved" baffle identical with the 3927136 except shorter. However, I believe this baffle is designed for the "5 quart" oil pans used for most 1970-72 LT-1 and 73-74 L-82. The "except HD 4 speed" designation excludes those 1970-72 ZR-1 which were built with the "6 quart" oil pan. No external baffle was ever cataloged for 1970-72 with HD 4 speed (i.e. ZR-1). Of course, they did have a baffle, but it "slipped through the cracks" as far as SERVICE cataloging was concerned.

If anyone has a known GM #3820001 oil pan around (i.e. original 1963-65 "6 quart" oil pan), I'd love to know what the measurement is between the side rail gasket surface and the internal baffle. Also, a picture of the internal baffle would help. I have a few NOS GM #359942 oil pans [none for sale] which I presume have the same baffle height as the "mysterious" GM #3956670 and I can measure the baffle height for those. If there's a difference, then we'll know how the 3820001 differed from the 3956670 and the 359942.