96 classic gas help

[eaglebreath]

I am very interested in buying a 96 caprice classic ,which is a creampuff.
It has the 4.3 v8 , and I am skeptical at the manufacturers city/hwy.
mileage ratings, 18 and 28mpg. Can such a big car get that mileage?
Can anyone out there confirm these numbers?

['97ventureowner]

It's possible. My '95 Roadmaster (cousin to the Caprice/Impala)has the LT1 V8 and I'm getting around 25 on the highway and high teens city driving.

[Blue Bowtie]

I feel 28 is a bit optomistic, but ALL USEPA fuel mileage estimates are optomistic. Realistically, 25 is not out of the question.

My '94 LT1 does over 26 in pure highway driving, and that's with heads/valves/cam/exhaust and programming and without driving it like a baby. To be fair, the reprogramming included enabling of highway fuel and spark modes, so it would probably be unfair as a direct comparison, and would be even better with the factory cam.

[96capricemgr]

When I still had the L99 it averaged mid 20s highway full loaded running the AC and driving somewhat aggressively. Current motor is well over twice the power the L99 made and with drivetrain mods to support that sort of setup I still get high teens in mixed driving. All the highway trips I made were too the race track so I have that skewing the milage and still averaged 19.x on those trips.

With the L99 the only time I got high teens for milage was when it had serious mechanical issues like broken exhaust manifold bolts.

[Blue Bowtie]

I think someone is running a bit steeper gear, and probably a bit of a loose converter, costing a few MPG up to lockup.

[96capricemgr]

Originally Posted by Blue Bowtie

I think someone is running a bit steeper gear, and probably a bit of a loose converter, costing a few MPG up to lockup.

Yes that is what I meant by drivetrain mods to support the current power, I should have elaborated. 3400stall and 3.73s are the numbers and 470-480fwhp.

My point was if I average what I do mid 20s all highway is certainly attainable for stock vehicles in a good state of maintenance.

One overlooked milage factor is tires. I lost milage with both the 255/55/17 rubber and the 215/75/15 snow tires over the original 215/75/15 (continuous circumfrence ribbed) all season Generals, that were horrible in the snow.

For a mild climate non-performance driver, tire selection will absolutely help economy and I think this is somewhere most of us endup missing EPA ratings, performance tires or snow tires hurt economy, but it is a tradeoff many enthusiasts are willing to make.