Posted By: 6PAX
Big block 727 question - 11/05/19 03:40 AM
Can someone tell me what the difference is between a 440 non-hp 727 and a 440 hp 727? The transmissions I am looking at in particular are 3681056 and 057 for late 1972 and 1973 cars.
Posted By: 451Mopar
Re: Big block 727 question - 11/05/19 07:48 AM
I don't know by part number, but the HP trans usually has the 4-pinion front planetary gear and 4-clutch front drum, and some non-HP just have 3-Pinion, 3-Clutch Drum.
Not sure if the governor is a different shift point.
The parts interchange, so no problem upgrading a low performance to HP specs.
If in the budget, Bolt-in super sprag and Billet front drum (5-clutch) are great upgrades for safety and performance.
Posted By: blewbyu
Re: Big block 727 question - 11/05/19 12:36 PM
I don't know by part number, but the HP trans usually has the 4-pinion front planetary gear and 4-clutch front drum, and some non-HP just have 3-Pinion, 3-Clutch Drum.
Not sure if the governor is a different shift point.
The parts interchange, so no problem upgrading a low performance to HP specs.
If in the budget, Bolt-in super sprag and Billet front drum (5-clutch) are great upgrades for safety and performance.
I believe only Hemi trans had the 4 gear planetary?
Posted By: John_Kunkel
Re: Big block 727 question - 11/05/19 07:10 PM
The earlier 440 HP had 4-pinion planetaries front and rear, 440 standard performance had them in the front only. Any 440-4 will have 4-disc front and rear clutches. Governor is different in the HP.
In '72 most 440's had the 4-pinion in the front only.