to get 500 miles from a tank or 35 mpg in a 2000 Monte Carlo SS with roughly 170k? My friend who lost his white monte awhile back in a wreck (I had a thread about it with pics), is looking at getting an 04 Gold Impala with gold leather and a 3800 with 157k for 6k and claims he can't wait to get it because then he will be getting 35 mpg again I told him I literally know of no one btween owing a Monte/Impala/Grand Prix.Bonneville etc etc anything with a N/A 3800 that gets 35 mpg. He basically went on to tell me when he had his white Monte he did and usually got 500 per tank on regular 87 gas. Has anyone here gotten that? Just wondering if I was crazy of if its totally possible with every tank like he claims.

 

It's definitely possible. I know of a guy who's ex-gf's 97 Grand Prix gets 36mpg on the highway. It was tuned so that helped but the exhaust was redone as well. He thinks with a little more fine tuning (he still erred a little on the rich side cause he didn't have a wideband, just not as rich as the stock GM tune) he could eek out a little more fuel mileage.

I got about 460 miles out of around 13 gallons (can't remember the exact #s) in my 96 3800 powered Camaro. Granted, it was a stick so less driveline loss but keep in mind the 96 Camaro ECM was non-flashable, so I could fine tune things.

For that matter, when I went to NC for Thanksgiving I got 33mpg. That's through the mountains (the 35mpg I got out of my Camaro the time I measured was through the mountains as well).

 

Best I've ever achieved was 33 mpg on the highway driving extremely good.. haven't gotten anywhere close to that since I starting modding..

 

Same here 33 is my top so far, and his car was all stock minus the grill and the 5th gen painted monte wheels.

 

Thats awesome, I have normal driving habits my higest speeding is 63, since most roads around here are 55 mph, and my 3400 got a tops of 430 a tank.

 

When I first removed my cat I was getting 38 mpg than the check engine light came on & it went to hell on mileage lol, when I went to Vegas last year with the Monte I avg 460 miles to a tank

 

my Monte last year did 38 average mpg going from Illinois to Minnesota, the entire trip was 640 miles and i had filled up the car with 16.5 gallons before i took off, soon as i got to my destination (i had the low fuel indicator on for a while by then) i filled up again and took almost exactly what i put in 16.4 gallons that puts me at 38.8 miles to a gallon, i drove 65-70 on cruise almost the whole way there no stops.

 

I don't know how you guys are hitting 30 mpg with your 3800's. The best I've ever done is 24 mpg, even on the highway. The best I've managed with dad's 3400 LS is 27 mpg. I don't beat on them either. Fuel filter and air filters are new (suggestion from the forum). I'll be doing spark plugs on both cars soon, but I don't expect that to give me a 6 mpg gain on my 3800 and a 3 mpg gain on my dad's 3400.

 

i got 33 mpg on mine and that's the 3400, so should be getting better mpg.. that was highway, with CAI and tune... i'd say it's possible, outside of driving in the city

 

On a long highway trip driving easy I think it's possible. I was averaging about 230 or so on a half a tank ( I usually don't run it down past half). I haven't checked it lately but now I'm only driving in the city, no highway.