Real Fiero Tech

I got an email from someone interested in putting a SBC in his car, but does not want to use the stock transmission.

He wants to know if there is a stronger transmission that will fit a SBC in the Fiero, is there one?

I figured if there was people would be using those rather than blowing up stock trannies, but I don't know much about swaps.

4t65E

4t80E

Thats it. That is if you want to make real power and not V8Archie kiddie power.

That's what he's looking for, thanks :thumbleft:

You can have a 4T60 or 4T60e built to handle the power, but by the time you are done, you will be in farther than for a built 4T65e.

I say built 4T65e. The 4T80e will hold up to a typical SBC stock, but will weigh double what the 65e will, and will cost just as much.

Supposdly if he wants a manual, the f40 6speed is rated for a higher torque and a heavier load, but it still isn't going to be storng enough for the v8.

Aaron wrote:You can have a 4T60 or 4T60e built to handle the power, but by the time you are done, you will be in farther than for a built 4T65e.

I say built 4T65e. The 4T80e will hold up to a typical SBC stock, but will weigh double what the 65e will, and will cost just as much.

FWIW, I sold my 4T80E for $100 here on the forum:

http://realfierotech.com/phpBB/viewtopic.php?t=7029

I've seen them on craigslist for $200 and under pretty regularly. Usually from wrecked cars that somebody pulled the engine out of for a hot rod or to replace a bad engine (head gaskets) in their Caddy. I would say that $200 or less is pretty damn cheap, cheap enough that it might be worth the extra weight for most drivers. Those trannies are like a frickin' tank, that's for sure.

Bryce

4T65E-HD is my vote.

$200 isn't bad at all. Unfortunately a lot of places see that Cadillac symbol and think everything associated with it is pure gold, especially with the drivetrain.

However, even at the same price, I'd go with the 4T65e-HD, because of weight, availability, and buildability.

The 4t80e's are worthless. They hardly ever go out, so with no buyers, they go cheap. I've never seen one sell on ebay for more than $200. Most are about $100.

So if price is a concern, go with the 80e. If not, go with a 65e-HD. They're put behind LS4's with 300ft/lb so they'll last behind some moderate torque. They can be built to handle a lot more power as well.

Anyone have any info on the common gearing on the 80? I think the 300 hp version had 3.71:1 final=third, but what about the 275? Also, is there a 3.1-3.2:1 for the 65?

Atilla the Fun wrote:Anyone have any info on the common gearing on the 80? I think the 300 hp version had 3.71:1 final=third, but what about the 275? Also, is there a 3.1-3.2:1 for the 65?

According to GM Powertrain and wikipedia:

http://media.gm.com/us/powertrain/en/pr ... /08car.htm
http://en.wikipedia.org/wiki/GM_4T60-E_transmission
http://en.wikipedia.org/wiki/GM_4T80-E_transmission

4T80E factory final drives: 3.71 or 3.11
4T65E factory final drives: 2.86, 3.05, 3.29, 3.69

Thanks!