fury fan
Senior Member
If wanting to go the GM-trans route, there are more options to consider.
700R4, 4L60E-series (electronic version of the 700R4) and 4L80-series. Oh, and 6-speeds also, but those are huge $$.
The electronic control boxes for the GM electronics are <$1000. I saw a manual VB kit for the 4L60 series, too. Perhaps there is one for the 4L80?
The later 4L60 series has a bolt-on bellhousing, and there are aftermarket conversion bells available, both steel and aluminum, for SB and BB. I've heard reports that the steel ones (Quick Time) sometimes have fluid leak issues. The 4L60 is a smaller trans, but in the higher-torque versions (4L65 and 4L70) it's pretty stout for its size (and can be beefed, of course). It has a 3.0x first gear ratio, so better suited to lower-torque vehicles that need the help, where you tolerate the large ratio step to 2nd gear.
The 4L80-E has the modern-day durability reputation of the 727. But it's significantly larger in girth, so more difficult to install. A 4L6x trans will probably fit with no tunnel mods.
The players, in no particular order:
Gear Vendors (has a less-beneficial OD ratio than all the others)
NAG1 (mercedes-based)
A545RFE (5-speed pickup trans)
8HP70 (although the gear ratio spread is so wide that axle ratio/tire height is important, and in some installations all 8 gears might not be practical to use)
A500RH
A518RH
4L60E-4L65E-4L70E
700R4
4L80E
6Lxx-E
The biggest question to the original question - is this for a SB or BB engine?
That *really* drives what transmission makes more sense.
700R4, 4L60E-series (electronic version of the 700R4) and 4L80-series. Oh, and 6-speeds also, but those are huge $$.
The electronic control boxes for the GM electronics are <$1000. I saw a manual VB kit for the 4L60 series, too. Perhaps there is one for the 4L80?
The later 4L60 series has a bolt-on bellhousing, and there are aftermarket conversion bells available, both steel and aluminum, for SB and BB. I've heard reports that the steel ones (Quick Time) sometimes have fluid leak issues. The 4L60 is a smaller trans, but in the higher-torque versions (4L65 and 4L70) it's pretty stout for its size (and can be beefed, of course). It has a 3.0x first gear ratio, so better suited to lower-torque vehicles that need the help, where you tolerate the large ratio step to 2nd gear.
The 4L80-E has the modern-day durability reputation of the 727. But it's significantly larger in girth, so more difficult to install. A 4L6x trans will probably fit with no tunnel mods.
The players, in no particular order:
Gear Vendors (has a less-beneficial OD ratio than all the others)
NAG1 (mercedes-based)
A545RFE (5-speed pickup trans)
8HP70 (although the gear ratio spread is so wide that axle ratio/tire height is important, and in some installations all 8 gears might not be practical to use)
A500RH
A518RH
4L60E-4L65E-4L70E
700R4
4L80E
6Lxx-E
The biggest question to the original question - is this for a SB or BB engine?
That *really* drives what transmission makes more sense.
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