That makes perfect sense. If you can't spool your turbo you won't be getting enough air. But with a stock turbo that spools with stock fueling you get 12 to maybe 14 hundred degrees EGT. Add fuel and you won't have enough air to burn it and EGT goes up. Put in that elbow and screw it in so you max out the stock turbo that mine will pull 28PSI. With the stock programing and no elbow it pulls 20 psi. 28 psi puts more air in and burns the fuel better before the exhaust valves open and so the EGT goes down. So a small turbo as the second turbo in a twin set up that is somewhat larger the small turbo spools quickly and provides enough exhaust to spool the bigger turbo and really lower the EGT. I want twins but I just want it for the better fuel economy and EGTs. I have no intention of turning my engine fast enough to make all the horsepower. I have no concerns about it hurting the engine, I know it could run at 3,000 rpm for a bazillion miles. It's for my comfort and the efficiency of my fuel usage. Most tuners don't have the same concerns that I have, I know that. They want horsepower and are willing to spin the engine high enough to get that. I'm not. I like the torque and fuel efficiency at lower RPM. Perfect for cruising down the freeway but not so great for the drag strip or the truck pull. I'd like to have a 5.9 in a 72 cadillac with 2.50 gears and an overdrive. Imagine a C-7 Corvette with a Duramax (only because a corvette couldn't handle a Cummins.).