How can this be?!!!

[PeteA216]

On my 1984 Chevy Caprice w/ the 305 V8, I've gotten rid of the computer, all emissions, and no longer have the torque converter lockup. I also have an edelbrock performer carb. Now with all this, you'd think I'd be getting horrible gas mileage especially with the exhaust so rich you can see the black just crusting all over the tailpipe.

Well I just got back from taking a 720 mile roadtrip to and from the mountians (Adarondacks) and it took me, NO LIE, only a tank and a half for the entire trip. I calculated the gas mileage to be on average 23 MPG (26 highway, and 20 city... well not actual city, but hilly, hick road driving) I want to know how is this physically possible?! I was flipping out at how miraculous this was. I never thought a V8 was capable of this kind of fuel economy, especially while revving so high on the highway w/o the TCC. The ETA estimated for the '84 Caprice sedan w/ the 305 was 17 MPG City, and 21 MPG Highway. Im so psyched right now! Its not even lyk the car's slow... its got way more balls than when it ran with the ECM. Any explinations guys??

[GreyGoose006]

i guess you just freed up all the horsepower that was being lost in the emissions crap. either that or you did your math wrong LOL.

[PeteA216]

Trust me, I checked my math numerous times.

[GreyGoose006]

i would too. hey whatever. dont complain or you may get your bad mileage back...

if you have cruise control, it could help your highway mileage, and driving easy could help your city mileage...

quick question... why get rid of torque converter lockup... i hate electronics, but this is FREE mileage...

[silicon212]

Originally Posted by GreyGoose006

i would too. hey whatever. dont complain or you may get your bad mileage back...

if you have cruise control, it could help your highway mileage, and driving easy could help your city mileage...

quick question... why get rid of torque converter lockup... i hate electronics, but this is FREE mileage...

If he has an overdrive and has forgone the converter lockup, he can expect to lose both 3rd and 4th gear in fairly short order (the 3-4 clutch will fail due to heat).

Oh, Pete? Don't expect it to run like this all of the time. I once averaged 24MPG on a 1975 Grand Am running near 100MPH, on a stretch of highway (topped off in Kingman, drive I-40 east to Flagstaff, topped off again and about 4 gallons total usage - made the run in just under an hour - 96 miles). This on a car that averaged about 8 in the city, and 14 on the highway. It turned out to be an anomaly, because I never again hit that except in my Caprice with OD (it does this mileage on the highway normally).

[G-man422]

Maybe you guys had the wind blowing toward the way you were going...that could really reduce air resistance.

[silicon212]

Originally Posted by G-man422

Maybe you guys had the wind blowing toward the way you were going...that could really reduce air resistance.

Not when you're climbing from Kingman (1000 elevation) to Flagstaff (7000 elevation). I did think of that, but I think it had more to do with "drafting" than a tailwind.

[GreyGoose006]

were you maybe going down hill??? that would help

[silicon212]

Originally Posted by GreyGoose006

were you maybe going down hill??? that would help

No, re-read what I wrote - I climbed in elevation from 1,000' ASL in Kingman to 7,000' ASL in Flagstaff. That's 6,000' climb in 96 miles, a little over a 1% ascending average grade.

Edit, sorry Kingman is 3,300', just looked it up, so that's about a .5% grade, still a climb.