4L60E Versus 4L80E Horsepower Needs/Losses?

[LS1GMCTruck]

In other words, how much horsepower is lost by using the 4L80E, over the 4L60E? thanks

[ls1ram]

In other words, how much horsepower is lost by using the 4L80E, over the 4L60E? thanks

I think its mainly the converter, they are normally 15lbs heavier, may cause the motor to rev a bit slower....

[pl4yboy]

Small diameter converter helps a lot. That, and the 4l80 has larger components that just take more power to spin.

[sprayedenali]

everything about a 80 is bigger and heavier, so therefore it will have more parasitic loss than the 60, id GUESS around 4%-6% more than a 60, but i really have no idea

[aj06bolt12r]

I don't have any experience with destroying a 60e. I've never owned one. But from what I've been reading, if you make much more power than stock with bolt ons and a tune and you plan to drive aggressively a 60e will become a money pot with no bottom. I've also seen people claim that they have been running well over 500rwhp through a stock 80e with a shift kit with no problems. I've seen it said that the stock 80e is stronger than a race built 60e. If that's is all true than does the few% tq loss really matter to you? I don't see how it could. Seems like it would b cheaper to make an extra 25ftlbs than it would be to repeatedly repair a 60e. Just plan your rear end ratio and tire size around the very tall 1st gear ratio found in the 80e. The truck in my sig doesn't shift out of firsts untill over 60mph and can't spin the tires for more than a few feet on dry pavement. And its putting about 360 ftlbs to the ground. I'm getting either 4.88 or 4.56 gears next mod.