Does anyone know the average percentage loss with the 80E in the crewcabs?

I read it's 22% for the crewcab 60E.

 

It must be significant because of all the stock 6.2 dyno's I've seen on here the #s are much less than Automatic equipped LS2 vehicles. Thinking about getting a baseline dyno on my truck before the headers go on with a dyno tune since I'm betting the 9.5" rear might rob even a few more. 25% seems right if the 6.2/6L80Es are dynoing 310-315rwhp stock.

 

Thats what i was thinking if not a lil bitmore.

 

Four wheel drive trucks will also lose more since they are going through the transfer case as well.

 

I agree.