Higher EGT's with Banks Exhaust??

[3-Fan]

I had my first big pull (to the NASCAR race) with my new Banks exhaust this weekend with the 5'er. Probably close to 17,000# combined weight. When I made the same trip down through West Virginin back in March with a little less weight in the truck and camper with the stock exhaust, my EGT's were lower (50-100 degress) than this weekend with the 4" exhaust. But on the way home, my EGT's were consistitly 100+ degress lower than with the stock exhaust. I took some pretty good mental notes of my EGT's on my trip in March to compare to what they would be with the new exhaust.

I hit 1200 degress rather quickly on the way down and then backed off since I didn't want to get much hotter. My max EGT on the way down in March was 1090. But never got above 1100 on the way home (max on the way home in March was 1187). I tried to keep the speed limit pulling so I was pushing the truck relitiviely the same back in March as I was this past weekend. Hot Juice was on level 2 both times. The air temp was probably hotter yesterday than is was on the way down on Thrus and definetly in March.

Could this have been just some fluke that the EGT's were hotter with the new Banks on Thursday than my previous trip? What other factors could have influnced the EGT's like this?

Over all been impressed with the Banks exhaust. It was my first ever exhaust job and took me about 3 hours from start to finish. I expected it to be louder. IIRC, the stock exhaust may have been slightly louder, but the Baks definetly has a deeper grumble, but low volume.

Could I have put the muffler on backwards by mistake? What would that cause the system to do.

Thanks!!
Greg

[TST Tech]

Greg'
Did you notice an increase in the boost pressure with the larger exhaust?

[GMCTRUCK]

Your egts should be lower. The exhaust should definitely be louder than stock. Yes, you could have put the muffler in backwards. I believe there is a flow arrow stamped into the muffler to show the direction of flow. Do you remember the direction of the louvers inside the muffler. The air should be flowing with the louvers not against like a cheese grader.

[3-Fan]

I did notice a slight increse in the Boost readings. Of course my SPA gage (boost side) does give me fits sometimes. I haven't had the time to properly ground it yet so am getting some skewed numbers at times. Only when it is cold though. It does spool up alot quicker though.

I placed the muffler per Banks instructions. The stamped labeling on the muffler towards the front of the truck.

Maybe I'll pull the muffler to see if I have the louvers right. But if I had it in backwards, wouldn't it be louder than if I had it the correct way?

Thanks guys!!

[a64pilot]

I think you answered your own question. Outside air temps were hotter. Outside air temps will have a definite affect on EGT's

[sdaver]

a little headwind can make a big difference in wind resistance...............and increase the load......dave

[1822]

Summer diesel fuel has more BTU's in it than winter fuel. This often causes higher EGT readings. I have always seen a 100-200 degree difference driving the same route at different times of the year. This is a lot more evident in the 6.5 than in the 6.6 because the 6.5 can overfuel where the 6.6 does not.