700r4

[lilhomy10]

what do you think about going with a 700r4 on my 461 stroker in a 77 bonne instead of the th400. i should have bout 500+hp 500lbtq. ican get a fully done warrantied for a yr up to 650hp for 1500 and 160 for adapter kit.

[79Bandit]

if you have the extra cash why not...but the th-400 is a pretty decent trans.. and if your in a bind i would stick with it i have a 461 and i plan on using the th-400

[MagicRat]

IMO it depends on the use it gets. For racing, the 400 is best; stronger and with closer gear spacing than a 700 through the first 3 gears. This is best for a relatively peaky engine.

But for any kind of highway use, the 700 is the way, especially if you have a nice, broad torque curve.

[MrPbody]

Actually, TH700R4 is NOT the best choice for the Pontiac. TH200-4R is considered stronger and will bolt up to the Pontiac without an adapter, where the 700 will need one. A good friend is a transmission builder. He says, if you install the aftermarket sun shell and sun gear (TCI, Level 10, etc.), and use good replacement parts all through it, 200-4R is WAY past 700 for both toughness and shift quality.

All that being said, TH400 is FAR stronger than any of the OD transmissions. If the 461 is built "right", TH400 may be your only good choice. Of course, all the low-end power 461 makes, can be put to good use by simply raising the axle ratio. Smokey Yunik said it best, regarding Pontiacs and performance: "Don't REV it up, GEAR it up...."

Jim

[sub006]

mrpbody is correct. The 700R4 is not noted for its strength or longevity. All kinds of beef-up parts are available but they don't address the basic problem of key bearings that are too small and/or made of inferior metal. Typically 150,000 miles tops in GM truck service. With auxiliary oil cooler and Mobil 1 ATF my last Suburban 700R4 made it to 215,000 gentle miles before bearings fragged. Now trying for more with Redline D4 ATF, which should help.

Still, at 16-17 mpg highway and 30,000 miles per year, I can't see going back to a 3-speed auto which might give 12 with my 3:73 rear end! Gas savings will easily buy a pro rebuilt trans every six years.