The Ford Barn

Ross F-1 · 01-08-2015, 02:33 PM

Are the bellhousings from G-series flat-6's the same bolt pattern etc. as the H-series flat-6's?

cmbrucew · 01-08-2015, 02:49 PM

Ross
G is part # 6394 41-47 pass, com, truck 6 cyl G
H is part # 6392 47-48 pass 6 cyl H, 47 trucks 6 cyl H
Bruce

Ross F-1 · 01-08-2015, 03:12 PM

Thanks Bruce! Do you know if they are physically interchangeable? I know some were steel, some cast iron, which could mean a different P/N but they could still interchange.

DD931 · 01-08-2015, 07:06 PM

I don't know about passenger cars, but truck transmissions use the 78- series case for trucks '42 - '50/51 with both G and H sixes. After that they used the similar side-shifter case for column shift. So, I would say they are the same as far as matching the transmission, but don't know about the engine side. Hope this helps!

Ross F-1 · 01-08-2015, 08:24 PM

A member of the truck forum is swapping out one flat 6 for another, and the BH doesn't appear to align with the new engine's rear face holes. It's a cast iron BH, which would be Truck. It has the two lowest holes for the large bolts (at about centerline) tapped, meaning the bolts come from the front. Only two of the upper holes align with holes in the block. The old engine is gone, so we can't tell if it was a G series engine.

There's no issue on the BH-to-trans side, he's keeping the trans that was hooked up to the old engine and BH. (And it's a truck trans).

49fordv8f4 · 01-08-2015, 09:40 PM

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Ross, The photo he posted of the old engine has the distributor on the side, so I believe that would be an H. Apparently the G sixes had their own transmission case, as the half bell on the transmission was a different shape. It has a bump sticking out of the side of the bell to cover the starter drive.
Mark

1946 ford convertible · 09-28-2024, 10:39 AM

Hello, so, will a 49 H series use BH part #6392 to bolt up a 1946 3 speed side shifter? Thanks, Matt

38 coupe · 09-29-2024, 06:37 AM

The G series engines used a bell housing and transmission case specific to those engines. However, the G series had a removable bell housing. The G bell housing assembly can be installed on a later H or M series engine block and the later engine bolted to a G series transmission. 25 years ago dad had a 46 sedan with an H series engine bolted to a G series transmission using all factory parts.

rotorwrench · 09-30-2024, 05:41 PM

If I remember correctly, the H series six cylinder engines had a plate that bolts to the engine and the clutch housing bolts to the plate. The G series had a full clutch housing that attached to the engine. The fit there is likely the difference. The transmissions didn't change much in the years from 1932 up through 1950. In 51, the gears changed in all the Ford 259 series transmissions to what was referred to as the diamond shaped gear tooth. For pickups, the top shift was used for one more year period which was changed over in 1952 at some point.

mercman from oz · 09-30-2024, 06:04 PM

1942 Ford Six Cylinder Engine and Gear Box.

Rangerstan · 02-02-2025, 12:57 PM

Had to take all my G transmission internals and put them in a v8 case . Putting an H into a 1946 coupe

01-08-2015, 02:33 PM	#1
Ross F-1 Senior Member Join Date: Nov 2010 Location: NM Posts: 2,443	G-series vs H-series Flat Six BH's Are the bellhousings from G-series flat-6's the same bolt pattern etc. as the H-series flat-6's? __________________ '52 F-1, EAB flathead

01-08-2015, 02:49 PM	#2
cmbrucew Senior Member Join Date: Dec 2010 Location: North of sandy ago, CA. Posts: 2,080	Re: G-series vs H-series Flat Six BH's Ross G is part # 6394 41-47 pass, com, truck 6 cyl G H is part # 6392 47-48 pass 6 cyl H, 47 trucks 6 cyl H Bruce __________________ Works good Lasts long time

01-08-2015, 03:12 PM	#3
Ross F-1 Senior Member Join Date: Nov 2010 Location: NM Posts: 2,443	Re: G-series vs H-series Flat Six BH's Thanks Bruce! Do you know if they are physically interchangeable? I know some were steel, some cast iron, which could mean a different P/N but they could still interchange. __________________ '52 F-1, EAB flathead

01-08-2015, 07:06 PM	#4
DD931 Senior Member Join Date: May 2010 Location: PA Poconos Posts: 723	Re: G-series vs H-series Flat Six BH's I don't know about passenger cars, but truck transmissions use the 78- series case for trucks '42 - '50/51 with both G and H sixes. After that they used the similar side-shifter case for column shift. So, I would say they are the same as far as matching the transmission, but don't know about the engine side. Hope this helps!

01-08-2015, 08:24 PM	#5
Ross F-1 Senior Member Join Date: Nov 2010 Location: NM Posts: 2,443	Re: G-series vs H-series Flat Six BH's A member of the truck forum is swapping out one flat 6 for another, and the BH doesn't appear to align with the new engine's rear face holes. It's a cast iron BH, which would be Truck. It has the two lowest holes for the large bolts (at about centerline) tapped, meaning the bolts come from the front. Only two of the upper holes align with holes in the block. The old engine is gone, so we can't tell if it was a G series engine. There's no issue on the BH-to-trans side, he's keeping the trans that was hooked up to the old engine and BH. (And it's a truck trans). __________________ '52 F-1, EAB flathead

01-08-2015, 09:40 PM	#6
49fordv8f4 Senior Member Join Date: Aug 2013 Location: Yellville,AR Posts: 222	Re: G-series vs H-series Flat Six BH's Sponsored Links (Register now to hide all advertisements) Ross, The photo he posted of the old engine has the distributor on the side, so I believe that would be an H. Apparently the G sixes had their own transmission case, as the half bell on the transmission was a different shape. It has a bump sticking out of the side of the bell to cover the starter drive. Mark

09-28-2024, 10:39 AM	#7
1946 ford convertible Junior Member Join Date: Aug 2024 Posts: 2	Re: G-series vs H-series Flat Six BH's Hello, so, will a 49 H series use BH part #6392 to bolt up a 1946 3 speed side shifter? Thanks, Matt

09-29-2024, 06:37 AM	#8
38 coupe Senior Member Join Date: May 2010 Location: South Texas Posts: 2,135	Re: G-series vs H-series Flat Six BH's The G series engines used a bell housing and transmission case specific to those engines. However, the G series had a removable bell housing. The G bell housing assembly can be installed on a later H or M series engine block and the later engine bolted to a G series transmission. 25 years ago dad had a 46 sedan with an H series engine bolted to a G series transmission using all factory parts.

09-30-2024, 05:41 PM	#9
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 18,006	Re: G-series vs H-series Flat Six BH's If I remember correctly, the H series six cylinder engines had a plate that bolts to the engine and the clutch housing bolts to the plate. The G series had a full clutch housing that attached to the engine. The fit there is likely the difference. The transmissions didn't change much in the years from 1932 up through 1950. In 51, the gears changed in all the Ford 259 series transmissions to what was referred to as the diamond shaped gear tooth. For pickups, the top shift was used for one more year period which was changed over in 1952 at some point.

09-30-2024, 06:04 PM	#10
mercman from oz Senior Member Join Date: May 2012 Location: Queensland, Australia Posts: 12,568	Re: G-series vs H-series Flat Six BH's 1942 Ford Six Cylinder Engine and Gear Box.