NSX Mod Turbo gets (nearly) 22 MPG!

[Black&Tan97Tnewportbeach]

Hey guys, on my recent return-run from vegas to orange county, I got 277.2 miles from 12.66 gallons of gas-o-line, putting the MPG at 21.89. This is pretty good I think, I drove pretty normal, averaging about 80-85 in mild traffic. I got boost several times, particularly in the hill climbs and passing pesky trucks. Also, I am running 370cc injectors and my SFMU raises fuel rail pressure when it senses boost, so its not EXACTLY a stock motor with just some extra air being crammed into it.

Has anyone else with any FAI system taken any MPG data?

Thanks & Happy New Year!!!

 

[Gerry Johnson]

I am getting 22.5 miles to the gallon with a passenger and running the A/C, I have 680cc injectors, running 15psi when under boost. I am running the Electromotive Tech-3 Engine Management.

 

[David]

I get 21 - 22 mpg at 80 mph. 720cc injectors and 510hp to the wheels on pump gas. Motec engine management.

 

[jackmac]

LOL Chris,
I average about 21 mpg too! Quite surprised but it's true.
JACK

 

[MvM]

My NSX is standard engine-wise.
Over the last year I averaged 8km/liter, which equals 18.8mpg. I can do better but then I have to watch my speed and not hit 8000 rpm so often. Getting 20mpg is not really difficult unless you go over 100 mph all the time

 

[Black&Tan97Tnewportbeach]

DAMM! Gerry & David you guys are running big injectors! Me & Jack have 370s both I think, but we only run 6-8 pounds or so. When we used 440's on mine it smoked like a jet engine at idle. How do you get such big injectors to be "daily-driver" friendly? Is it the engine management you had mentioned? Also, do you use a SFMU or is that what the engine management system eliminates the need for?

 

[sjs]

Originally posted by Black&Tan97Tnewportbeach:
DAMM! Gerry & David you guys are running big injectors! Me & Jack have 370s both I think, but we only run 6-8 pounds or so. When we used 440's on mine it smoked like a jet engine at idle. How do you get such big injectors to be "daily-driver" friendly? Is it the engine management you had mentioned? Also, do you use a SFMU or is that what the engine management system eliminates the need for?

I you are running 370s without additional engine management then the ECU must be dialing the duty cycle way back when in closed loop mode (most of the time for a street car) to keep the A/F near stoich. But even if it can do that I would think that there are times when it goes very rich as you leave closed loop. Not healthy. How is your part throttle response?

 

[Black&Tan97Tnewportbeach]

Part throttle response is great. I dont understand closed loop. It is a stock ECU, with a vortech SFMU, so it raises the pressure on boost, I have it set to 40psi static (at 0 vacuum), and at idle vacuum it drops to about 25psi. Then on boost it comes up considerably. I also have a TMC1 retarding the timing on boost.