[Blazin72]

About how much slippage in a torque converter can typically be expected when cruising at a constant 55mph at 3000 rpm? Will engine torque still have an effect on slippage under light load conditions?

The reason I ask is this. I just left a link for an RPM calculator to somebody who posted in the Engine forum and now I am somewhat confused. The calculator told me with 4.10 gears, 31 in tires (actual height about 30.5) and 3000 RPM (I used engine RPM and not tranny input shaft RPM) that I'd be cruising at 66 mph and I know that isnt the case.

Calculator

[M&M CUSTOM]

Many printed sources list the losses of a "stock" non lock-up automatic transmission at an averaged 12 percent or more.

[71C10]

Has your speedometer been re-calibrated for the rear gear and tire size?

http://www.tciauto.com/tech_info/speedo_gears.htm

From the NHRA site:
Before taking a closer look at the overall converter-selection process, one more item should be considered when dealing with high-stall-speed torque converters: efficiency. Typically, as stall speed increases, overall converter efficiency decreases ? though, to some degree, this relationship has been tightened in recent years. For example, a small-diameter performance converter will almost always slip more than a large, tight OEM converter. In most cases, a typical performance converter will slip from 3 percent to 5 percent at coupling (part-throttle conditions).

http://www.nhra.com/dragster/1999/is...echnology.html

[Blazin72]

Originally Posted by 71C10

Has your speedometer been re-calibrated for the rear gear and tire size?

Gears are original and the tires are pretty close to stock height too.