30 MPG daily driver muscle car... how would you?
 

We received a call today from a guy who is interested in an old car for a commuter.

He said he could go buy a new 30+ mpg car, but doesn't like 'em, so we is thinking about having us help him build a 1970 Nova he could use daily as a commuter car.

He wants to hit 30 MPG and still make some power.

Novas are not aerodynamic, but they are pretty light.

We found a '70 on Craigslist with a factory 6 and a 'glide that might make a good start. I'm thinking a 4.8 with a 6 speed manual, but he wants an auto.

How would YOU do it?

LS 5.3L with DOD with an OD auto tranny

I'm wondering if anyone has ever attempted to transplant a hybrid power plant into a classic muscle car? Some of the newer models of hybrids are pretty potent performers and high mileage. It might make for a very unique build, and unique builds are difficult to find these days.

hmm... DOD... interesting.

We had some thoughts on a hybrid a few years back..

I was/am getting about 24 mpg at 80mph with a LS1, t56 and 3:73's on highway.

Set the rev limiter to 2400, auto, and carbon everything, and as Steve Magnate calls it "radio delete". JK of course, but not sure 30 mpg is obtainable, but maybe as light as you can go and a 4.8 or 5.3 F.I.

Will a 4.8 6 speed get 30mpg in stock form?

I might consider a turbo ecotech from like an hhr ss with a solstice 6 speed.

I doubt that a 4.8 would hit it, but the ecotech is interesting.

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!

Here too:
https://lateral-g.net/forums/show...2Green+bean%22

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..

I had an HHR SS years ago for a shop run around and it got amazing mileage and ran 13 second quarter mile in stock form.

I have a ls1 with heads and cam, victor Junior intake with a TB on top. 4.11 gears and a T56. When we were on the power tour we averaged 26.8 mpg on the way home. we stayed around 75 most of the way on the highways.

My point to this is,, a regular LS6 intake, a smaller cam, and 3.42 gears.. we would have been over 30 mpg IMO..

Could you do a 5.3 with a small Cam, and a turbo? turbo really doesnt pull any power until you're into the gas.

good luck with the quest. Going to follow along.

I'd keep it simple. Do an aluminum block 5.3L, preferably a LH8. No dod, no vvt. Put a T56 behind it. You said that the goal is 30mpg, but you didn't say at what speed. Speed makes a huge difference with older cars that are not aerodynamic. So we must assume the speed limit, since the OEMs use that as their marker. Let's pick 70mph. I would then gear the car so in 6th gear it cruises around 1500-1600rpm.

I bet you'll get very close to your goal. Close enough that it'll be good enough.

Andrew

What about a Dart with a SRT4 in it?

I get the allure of the V8, but you can make a ton of power and still get decent MPGs with a turbo 4/6.

I love Green Bean! That is one of my favorite builds on here.

This is all great feedback. The 30 MPG is not really mandatory, just a target thrown out by the customer.

I'm digging the HHR Ecotech idea. Is that Solstice 6-speed an automatic?

Chevy did a 1933 coupe with an ecotec that made 500 horse power


http://www.autoblog.com/2007/10/29/s...let-coupe-e85/

I don't believe the Solstice ever came with a 6 speed. Both the auto and the manual were 5 speeds.

https://archives.media.gm.com/us/pow...2009/09car.htm

Andrew

:y0!:
How about an early Nova? 62-65 era? Pretty light, still a few out there that can be had for reasonable price. Use a v-6 out of a new Camaro (323hp) with auto, and gearing. Unique, not a new idea but is different. The new Camaro is roughly 3700lbs and the nova would be less, helping the efficiency of the v6. Just another idea to throw out there.

Your right.

http://en.wikipedia.org/wiki/Pontiac...2.80.932009.29

http://www.ebay.com/itm/Chevrolet-Pontiac-Solstice-Sky-Ecotec-LNF-LDK-2-0L-Turbo-Engine-Brand-New-RWD-/171040302671?pt=Motors_Car_Truck_Parts_Accessories &fits=Model%3AHHR|Submodel%3ASS&hash=item27d2cbe64 f&vxp=mtr

110mpg & 400hp on E85
 

http://www.hp2g.com/main.html

This guy is from near my hometown in NW Ohio.

Pizza cutter tires and light wheels will get you a couple MPG's as well. Some 16's with 205's would fit the bill.

Thanks for the link

Anyone ever see under the hood of this car?

I have wanted to put this turbo engine into my 62 notchback VW for along time. Just no spare time.

So I wanted to check ebay real quick.

Just throw a Duramax diesel in it. Problem solved!

This Chevelle is a daily commuter, it has a Gear Vendors OD, and gets 35 MPG on his commute and ran 11s at the drag strip. It runs in the 9s now, so I'm sure fuel economy isn't so hot anymore, but I figured I'd throw it out there. It has our cage, VariShocks, and some misc pieces.

http://speednik.com/files/2013/02/di..._2-640x517.jpg


THIS CAMAROhas a Duramax, our front clip, and our Eliminator-II backhalf.

^^^^^ X2!
If it were mine, this is the route I'd be taking.
:thumbsup:

6 speed auto and 3:08 gears. http://www.tciauto.com/tc/6x-six-spe...tm-shifterhtml

Do a 5.3L for a bit more low end but an efficient cylinder ratio. And alot of Carbon Fiber.

Diesel swap, carbon fibre (hood/ trunk/ panels/ seats) and aluminum/ fiberglass (panels/ hood/ interior parts) where needed.
Also weight reduction of removing things that are not needed, (air conditioning/ carpet/ rear seats/ etc) depends on comfort of course. And aerodynamics of course, front splitter, rear diffuser/ spoiler that will help cut the car through the air and help with handling at the same time.

I would think of an Ecotec or a Ford Ecoboost power plant or as others have mentioned, a mild LS with low gearing and a 6 speed manual or auto or even a gear vendors overdrive.