Lateral-g Forums - 30 MPG daily driver muscle car... how would you?

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Quote:

Originally Posted by Shmoov69 (Post 594073)

Check out project Green Bean from 417 Motorsports, it's an earlier 66 nova more door and has a turbo'd ecotec. Not sure on the mileage, but bitchin car and Blake does AWESOME work, and I'm sure he'd tell you what he gets out of it.

Ha just beat you too it, check out the link above. :D

Very cool, I'll take a look. Thanks!

Gearing and aerodynamics are the 2 biggest factors for highway gas mileage.

No matter what engine you have, it needs to make the same torque to move a given car at a given speed/rpm, so as for engine choices, whatever can be the most efficient at that rpm and load is going to use the least fuel.

My 89 GTA with a LS1/t56 gets 28mpg doing 80mph. It still has the 3.23 rear and 27" tall tires, so with the .5 OD, it's very low cruise RPM at 80mph. I haven't played with the tune at all yet.

Unless someone is in the eco-modder crowd, Idk why people give a crap about mileage. The difference between 25 and 30 mpg isn't going to be a huge cost difference for the average driver.

Another factor is octane requirement. A car that gets 30 on premium, is going to cost more to drive than a car that gets 30 on regular.

My advice is to choose whatever engine and trans he wants, gear the axle as high as you can to get a cruise rpm that's as low as you can go with out being too low, have it tuned for mileage at that load and rpm, and be happy with what it gets.

How about using the drive train out of a wrecked, newer Camaro or Cadillac? By the time you put on a set of headers and a modified cold air intake, you'd be pushing around 450+ hp, more with a custom tune with it.

I'd also suggest maybe doing an almost full body flat floor with an integrated front splitter.

What about a C3 Corvette with a 5.3?

I think it's doable in that platform if you can keep it light. I was able to pull down 29-30mpg in a stone stock LS1/T56 in my IROC for several years. At the time the car weighed 3350lbs and had a 3.42 rear gear.

Also keep in mind that driving habits have a LOT to do with mileage AVERAGES.
My brother has a 99' silverado that gets 17 to 18, unless his teenage son drives the truck. Then he averages around 14. He always checks mileage at every fill up.

My stock '99 Vette got 31-32mpg highway all day long, but per earlier comments, it was pretty light, low and aerodynamic - -- none of which a musclecare will be.

IIRC - - It was also tach'ing about 1700RPM at like 80mpg!

What about doing a GM version of an Ecoboost setup? Use the DI 3.6 from the 5th gen or CTS with a small pair of turbos to help with the missing power. Drives in vacuum when you aren't in it and can be backed with a 6 speed auto.

Most major manufacturers say the DI setup is worth a big bump in mileage in heavier new cars. Plus you could tune it to run nice and lean in the cruising areas of the VE tables where the automakers can't.

Then do like others have said and work towards a very streamlined aero package. I think 30 could easily happen, unless the customer is talking about 30 average instead of 30 on the highway. Then all bets are off..