So, I take many long 250+mile trips, and I dont want to kill my fuel economy.

I've heard of turbos actually increasing gas mileage.

Granted, it all depends on how it's driven... But does anyone with a Turbo/Super installed have any data on gas mileage, after forced induction, on the Renesis?

Any predictions?

 

Around town driving it has gone down a little bit, get maybe 180 miles, whereas I used to get about 200 miles per tank. On the freeway for long trips, no noticeable difference. About 250 miles per tank.

 

If I can get my extra Shell card back from my daughter - I will get better gas mileage

How does the turbo behave with cruise control on?

 

I tried the cruise control on my way up from San Diego. Unfortunately, since the turbo is making boost at around 3000 rpm & I had set the CC on for around mid 70's/4000 RPM it was on/delivering boost & the EGT temps were going up. I don't think CCat 70 mph+ is a good thing. You have to vary speeds a bit so that the EGT can go down & boost isn't constantly on.

 

The turbo shouldn't be on unless you're also giving it a lot more throttle than normal cruising . . . . . . .

Though I did suspect the gearing would be disastrous with a turbo once I went on a long road trip and found my 6th gear cruised at around 4000 rpm. I'd like wider gears or a 7th one for the turbo.

 

The boost starts at 3000 RPM, and when you are cruising at 75-80 mph we are right around 4000 RPM, so the turbo is running. Not much but it is twirling so heat is building up. Since it was on cruise control, I was not giving it any throttle. Just went to high 70's set the cruise control on, & watched the EGT gauge. It steadily moved up about 200 degree C, and I decided to turn it off. It is the fact that our cars are running at 4000 RPM in 6th that the turbo is not good for the CC, unless you are doing under something like 65 mph. Like you said, we need a 7th gear, or we can't really use crusie control for the turbo.

 

Or you could get an ECU that will cycle the wastegate during closed-loop operation to get to a lower (nonboost) level. Would cause some lag tho. But there's likely a timer before it falls into closed-cycle at cruise, so it probably wouldn't feel all that different coming out than it does now. There's a definite hesitation when you hit the throttle in cruise as it switches modes (and hence a/f's). If you we're varying the throttle, it would stay out of closed loop and stay responsive.

 

Wow- this is a serious shortcoming I think- any thought on how this could be implemented?

Is there sucha think as a remote wastegate that could just be switched open?

 

Thats why I figured I'd ask this fuel economy question.

4k @ 80mph roughly... Figured the turbo would either be helping or hurting. But I hadnt thought of the turbo temp.

 

So what's the cruising MPG?