It seems to me that when you're making a Gasser get better mileage, you want to reduce exhaust backpressure...
Why wouldnt this apply to diesels too?
I do understand that if you're driving for economy, backpressure is nearly non-existent , but what about those of us that enjoy our torque on a more frequent basis?
I've read that the stock OBS
turbocharger has an approximate drive/boost ratio of 2:1. this would mean to me that most of the time, i'm under 10 psi
of backpressure, but on occasion (assuming the ratio above is reasonably accurate) I could hit as much as 50 psi
of backpressure... not good for fuel economy. ( yes, i realize that the heavy right foot is worse, but...)
I think that maximizing for economy should include those of us with little self control.
so- i've been thinking, of three things.
First: I've heard that Tubular headers greatly reduce spoolup time, and some say backpressure. I have heard that they also may improve economy. My only source so far is Jon_Ford (sp?) on here. Has anyone else used these? if so, what was your experience?
Second: Ceramic coatings. Ive heard these also reduce spoolup time by keeping exhaust heat in the exhaust.
third: Larger Exhaust housings. I understand that spoolup would be reduced with these, but you'd also have lower backpressure. Has anyone put a larger housing on?
another question on that topic- has anyone ever put on a performance turbo, such as the D66 or QSSB and gained mileage?
I understand that these may not make near the difference as just slowing down, or putting a aero-bed cap on, but sometimes, i just cant help but mash the pedal and listen to the turbo, engine and wind.