Originally Posted by Doobie

I tow my 5k trailer in 3rd gear and still have TC lockup. I only see boost on hills, on ramps and passing.
Without towing I used to get 18mpg hwy but after last mod, Radix, I dropped to 16mpg. I believe it is due to parasitic loss from the Radix.

Originally Posted by DrX

Depending on how your tune is setup, even if you aren't into boost, you could be running close to it where the tune is starting the transition toward maximum enrichment.

Originally Posted by 06vortecmaxxx

Its not into boost except when passing or overpasses. I"m thinking my tune is setup on the rich side. I noticed a lot of black soot on the bumper around the exhaust.
Were camping for the week, I"ll have to deal with it when We get home. Sucks only getting about 160 miles per tank.

Originally Posted by DrX

1 bar or 2 bar tune? If it is in boost all the time due to engine load, then you will be running at a richer AFR. It may be richer than it needs to be if you are just barely into boost. IIRC I used to get better fuel economy in 3rd gear when towing with my Radix because I was able to maintain enough engine vacuum to keep the bypass from closing. This was even though I was running at a higher RPM.

I believe that Magnuson used to sell "towing" kits that came with a larger pulley, so you wouldn't be into boost all of the time. If your truck does mostly towing, that makes sense. If you want to play, then you give up some major ponies with a larger pulley.

Originally Posted by DrX

1 bar or 2 bar tune? If it is in boost all the time due to engine load, then you will be running at a richer AFR. It may be richer than it needs to be if you are just barely into boost. IIRC I used to get better fuel economy in 3rd gear when towing with my Radix because I was able to maintain enough engine vacuum to keep the bypass from closing. This was even though I was running at a higher RPM.

I believe that Magnuson used to sell "towing" kits that came with a larger pulley, so you wouldn't be into boost all of the time. If your truck does mostly towing, that makes sense. If you want to play, then you give up some major ponies with a larger pulley.