MPG Q's
 

ok i need some tips on gettig better fuel HWY economy (IF POSSIBLE) timing is back down at 10 fuel pressure is at stock setting.... i still have 3.08 Rear end gears and im still getting 12-13 MPG... stock on the freeway i used to get 19-20 is it possible to get any better that 12-13.... (by freeway i mean cruzing at70-80 in 5th the whole way)

thanks

WOW, I get 21 MPG on the highway and 12 MPG in the city beating on it. I really dont do anything to make any changes to my MPG. I still have 19# injectors running at 42 PSI and im at 14 degres timing.

any more ideas????

please... i just added a Stock replacement KN that i got for free so im gonna see how that works on my week.ly treck to the valley (all freeway 50 miles)....

I get 19 freeway with 3.73s at 75mph.

I run 18 degree timing and 32psi fuel pressure on 24lbers.

Make sure your car is in good tune and give it more timing!

Skyler

When was the last time you gave the car a good tune up?(plugs, wires, pcv, ect....) I was getting like 12-15 when I first bought my mustang and once I gave it a good tune-up, to include the bad O2 sensors that were on it, I jumped up to 22-25. I think the kicker was the bad O2 sensors. Once I got those change out, it made a world of difference. Not that its your problem, just some suggestions. Hope you get it worked out.

Chris

I would also put in a thermostat (signature), if you don't have one in and you run that cold the computer is going to run open loop and consequently run real rich. try a 180 degree

You are going to stroke on this one. I drive 50 hard miles one way to work. Generally 40 of it are country/hwy 4lane. The last 10 are in the city. I travel at or above 75 on the hwy. I get 21/22 usually. My last race I drove 146 miles round trip to the track. Made 13 passes on the 1/8th mile track. Most of which were 8.30's (full 1/8th at 84mph). I got 21mpg round trip. On that cruise I usually get 26-27.9 maximum but travel only 55-65mph (filling up at the trackside). I have 3.55's and the car is 3127 with me in it. 351 heads, 19lb injectors and an EEC tuner with A9L EEC. Figure that one out. My last good v8 stang was a Stock 89 with 3.08 gears and never got over 23 or so and I treated it as if it were a hurse. My EEC tuner is set for a little leaner tune (hwy) but before this I was getting nearly the same mileage on it before the head/intake swap. Before I could muster an 8.80 on the stock engine. The engine came out of a stock 88gt with 99K miles showing when it was wrecked. The plug wires were 88 vintage as well as needing oil pan and valve cover gaskets. It will smoke decently on a 75 shot to show it's age. This car is an 83 fox coupe converted to mass air EFI from an 89. Talk about a builder. :)

i gave the car a complete tune up not 500 miles ago (exept the O2 sensors) and i just therw the thermostat in and the KN and i still got crappy MPG... im gonna go get new o2 sensors today....

????