70-Olds-442-convt

Which would be a better solution for a 1970 Olds 442 with a 455, a 200 R4 or a 4T80E?

I am looking to go with an overdrive transmission, my turbo 400 needs a rebuild and freally want an overdrive to cruise on the highway.

Any specific suggestions on what to look for or model years transmissions to avoid or target.

Thanks in advance for the help.

joe_padavano

Well, the 4T80E is a FWD trans used behind the Northstar engines. The "T" stands for transverse. I assume you mean the 4L80E. That trans uses TH400 gear sets and hard parts for first through third, so basically it is a TH400 with overdrive. The OD is always a better solution on the street, but this trans is larger and heavier than the TH400. Floorpan mods may be required, and since it's a fully computer controlled trans you will need a stand-alone controller. Unless you can find one of the 1991-93 diesel truck controllers, the aftermarket ones are substantial dollars. And of course, the 4L80E was never made with a BOP bolt pattern, so you need an adapter plate.

Consider a beefed 200-4R. A properly built unit will cost about $1000 less than a 4L80E with controller, adapter, custom driveshaft, and custom e-brake cables (also about that much less than a Gear Vendors installation) and bolts right into your car. You will need a longer TH350 driveshaft, but the crossmember stays in the same place as for the TH400, so there's no need to change the e-brake cables.

Aceshigh

4L80e is an indestructible beast.
Joe's spot on tho.....tunnel mods absolutely necessary.

I'm looking at these 2004R's for now because I can't get my T-56 in without
spending $1000 on parts I'm going to toss later anyways.

http://cgi.ebay.com/ebaymotors/2004R...Q5fAccessories