View Full Version : 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?
Vega$69
02-10-2015, 05:46 PM
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
TheJDMan
02-10-2015, 05:49 PM
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..
Kk1SR-8NkB4
glassman
02-10-2015, 06:50 PM
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.
ironworks
02-10-2015, 06:51 PM
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.
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.
kevin_l
02-10-2015, 08:11 PM
I doubt that a 4.8 would hit it, but the ecotech is interesting.
http://417motorsports.net/index.php/customer-builds/car-1
Shmoov69
02-10-2015, 08:12 PM
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.
kevin_l
02-10-2015, 08:13 PM
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!
Shmoov69
02-10-2015, 08:17 PM
Here too:
http://www.lateral-g.net/forums/showthread.php4?t=30130&highlight=%22Green+bean%22
T_Raven
02-10-2015, 09:15 PM
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.
JB400
02-10-2015, 09:42 PM
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.
ArisESQ
02-10-2015, 11:39 PM
What about a C3 Corvette with a 5.3?
LS1-IROC
02-11-2015, 03:52 AM
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.
Che70velle
02-11-2015, 04:25 AM
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.
wiedemab
02-11-2015, 05:10 AM
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..
ironworks
02-11-2015, 05:45 AM
I doubt that a 4.8 would hit it, but the ecotech is interesting.
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.
Moose
02-11-2015, 06:07 AM
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.
andrewb70
02-11-2015, 06:15 AM
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
Evan Iroc-Z
02-11-2015, 06:18 AM
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?
turnhard
02-11-2015, 07:03 AM
Chevy did a 1933 coupe with an ecotec that made 500 horse power
http://www.autoblog.com/2007/10/29/sema-2007-34-chevrolet-coupe-e85/
andrewb70
02-11-2015, 07:16 AM
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?
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/powertrain/en/product_services/2009/09car.htm
Andrew
Wissing72
02-11-2015, 07:34 AM
: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.
ironworks
02-11-2015, 08:00 AM
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/powertrain/en/product_services/2009/09car.htm
Andrew
Your right.
http://en.wikipedia.org/wiki/Pontiac_Solstice#.23GXP_.282007.E2.80.932009.29
ironworks
02-11-2015, 08:06 AM
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=item27d2cbe64f&vxp=mtr
OLDFLM
02-11-2015, 08:10 AM
http://www.hp2g.com/main.html
This guy is from near my hometown in NW Ohio.
craig510
02-11-2015, 08:12 AM
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.
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=item27d2cbe64f&vxp=mtr
Thanks for the link
http://www.hp2g.com/main.html
This guy is from near my hometown in NW Ohio.
Anyone ever see under the hood of this car?
ironworks
02-11-2015, 08:22 AM
Thanks for the link
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.
Chassisworks
02-11-2015, 09:48 AM
Just throw a Duramax diesel in it. Problem solved!
This Chevelle (http://www.chevyhardcore.com/news/1970-thriple-threat-chevelle-lights-em-up-duramax-diesel-style/) 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/diesel_chevelle_2-640x517.jpg
THIS CAMARO (https://www.facebook.com/media/set/?set=a.577138045712487.1073741857.360398240719803&type=3)has a Duramax, our front clip, and our Eliminator-II backhalf.
DBasher
02-11-2015, 10:26 AM
^^^^^ X2!
If it were mine, this is the route I'd be taking.
:thumbsup:
Vince@Meanstreets
02-11-2015, 10:38 AM
6 speed auto and 3:08 gears. http://www.tciauto.com/tc/6x-six-speed-transmission-package-gm-bellhousing-outlawtm-shifterhtml
Do a 5.3L for a bit more low end but an efficient cylinder ratio. And alot of Carbon Fiber.
HPIcustoms
02-11-2015, 11:11 AM
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.
srh3trinity
02-11-2015, 12:13 PM
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.
ironworks
02-11-2015, 12:15 PM
Does it defeat the purpose of the good gas mileage when you spend 100k in parts to get there?
If your concerned about saving that much fuel but willing to spend how ever much to accomplish it, seems kinda counterproductive.
SBDave
02-11-2015, 12:15 PM
love that Green Bean build
I love the idea of these alternative engines, unfortunatly the guys paying the bills usually just dont want to take any risk away from the LS norm. If I had my choice though......
kevin_l
02-11-2015, 01:27 PM
Does it defeat the purpose of the good gas mileage when you spend 100k in parts to get there?
If your concerned about saving that much fuel but willing to spend how ever much to accomplish it, seems kinda counterproductive.
Great point, You can buy a lot of gas for 50k :D
Chassisworks
02-11-2015, 01:30 PM
Does it defeat the purpose of the good gas mileage when you spend 100k in parts to get there?
If your concerned about saving that much fuel but willing to spend how ever much to accomplish it, seems kinda counterproductive.
Since when do muscle cars and counterproductive not go hand-in-hand? :lol:
I had a customer mention to me earlier today that he should have bought a Rolls Royce for the amount of money he was dumping into his Mustang. But anyone with the right wallet can go out and buy a Rolls Royce, I said, and his Mustang will be completely unique.
96z28ss
02-11-2015, 05:07 PM
I would start with a smaller lighter car.
1962-65 Nova is about 2500 lbs with the straight 6.
put the turbo charged ecotec engine in it from a Pontiac solstice. 28mpg
Shmoov69
02-11-2015, 08:57 PM
Well if you're thinking about Alternative fuels.... Blake at 417 Motorsports (green bean) also did a TT dura max in a 66-7 Nova wagon. He could tell you the mileage on that one as well I'm sure. :thumbsup:
http://www.hotrod.com/cars/featured/hrdp-1112-1966-chevrolet-nova-station-wagon/
GregWeld
02-11-2015, 09:20 PM
Did the customer change his mind now that gas is $2 a gallon... LOL
I agree with Rodger.... WTF does a guy care about MPG if he's spending 150K to build a car. To the folks that say strip everything out to save weight... who'd want to drive that every day?
MPG has been figured out by every OEM... small lightweight cars with tiny engines... or you buy a New Corvette and keep your foot out of it... but then why would you want a Corvette? LOL I don't get it.
cluxford
02-12-2015, 01:35 PM
I get 17 MPG out of a 61 Buick, driven daily (ave over 100 miles a day mostly Hwy driven) with a poorly tuned carbed 350 SBC,
It's heavy, not aero, and very poorly tuned.
30 MPG is very doable.
Anyone ever see under the hood of this car?
X2. I'm curious.
Did the customer change his mind now that gas is $2 a gallon... LOL
I agree with Rodger.... WTF does a guy care about MPG if he's spending 150K to build a car. To the folks that say strip everything out to save weight... who'd want to drive that every day?
MPG has been figured out by every OEM... small lightweight cars with tiny engines... or you buy a New Corvette and keep your foot out of it... but then why would you want a Corvette? LOL I don't get it.
The appeal for me is just to be different more than the mpg. But if the real reason is saving gas then yeah, that doesnt make much sense!
He does not want to drop a zillion on this car, he just does not like new economy cars and wants to see if something old could do the trick. I think using as many OE parts as possible from donor cars would help keep the costs down. The Duramax idea is killer, but just too much work for this project.
andrewb70
02-12-2015, 05:50 PM
He does not want to drop a zillion on this car, he just does not like new economy cars and wants to see if something old could do the trick. I think using as many OE parts as possible from donor cars would help keep the costs down. The Duramax idea is killer, but just too much work for this project.
Kevin,
I totally get the appeal. There is nothing cool about driving any econobox made today.
I think you first need to nail him down to a specific car. I would go with something that isn't super popular, readily available, under 3500 pounds, and cool (whatever that means...you'll know it when you see it...Cougar?). Then go with your idea of using as many OEM parts as possible.
I think this whole project can be done for under $10K (plus your labor).
Andrew
cluxford
02-12-2015, 10:04 PM
BTW
@ 30MPG x 60 miles travelled daily @ $2.50 per gallon for gas = annual fuel bill = $1,750 (50 weeks a year where all 7 days in the week travel 60 miles. Assumes some weeks will be less).
@ 15MPG it's double that
so the difference between 15 MPG and 30 MPG is an annual expense of $1750
OLDFLM
02-13-2015, 07:14 AM
Kevin,
I totally get the appeal. There is nothing cool about driving any econobox made today.
I think you first need to nail him down to a specific car. I would go with something that isn't super popular, readily available, under 3500 pounds, and cool (whatever that means...you'll know it when you see it...Cougar?). Then go with your idea of using as many OEM parts as possible.
I think this whole project can be done for under $10K (plus your labor).
Andrew
^^^ Agreed!
Any mid-60s big 3 economy cars with a modern economy powerplant would do the trick:
SRT-4 = 285hp/265tq... Dart/Valiant/Barracuda
EcoTec = 260-290hp/260tq... Tempest/Rambler/Nova/Corvair/AMX
EcoBoost = 310hp/320tq... Falon/Mustang/Comet
I'd DD any of the above! Just need to nail down the car!
andrewb70
02-13-2015, 07:38 AM
I'd keep it V-8 for simplicity sake and cost. All the above engine options are good, but direct injection and forced induction integration really start to add to the cost. A stock 5.3L will make more power than all of the above and the rest of the driveline can be easily sourced. It may not get 30mpg, but it'll be close. The trick will be to gear it so that at highway speed the RPM is 1600-1700.
Andrew
The customer wants a '70 Nova. Not the best aero, but kinda light.
I'd keep it V-8 for simplicity sake and cost. All the above engine options are good, but direct injection and forced induction integration really start to add to the cost. A stock 5.3L will make more power than all of the above and the rest of the driveline can be easily sourced. It may not get 30mpg, but it'll be close. The trick will be to gear it so that at highway speed the RPM is 1600-1700.
Andrew
And if we go V8, it would probably be a 4.8. Our mechanic Trevor has a 4.8 / 4L65 with a 3.73:1 gear in a '68 Chevy truck that gets upper teens for economy, and will burn the tires for blocks.
Chassisworks
02-13-2015, 09:24 AM
I sold my 65 Rambler American station wagon about a year ago. It got 24 MPG, 3 on the tree and Auto OD. Not a 70 Nova, but it had a lot more trunk space.
Fitz78ta
02-13-2015, 01:52 PM
Just my opinion, but I think you would be money (or fuel mileage) ahead doing a 5.3 over a 4.8. I know my foot stays further on the floor to get and keep the 4.8 in my work truck moving more so then my wife's Tahoe or my old personal truck with 5.3's in them.
Also the tune can play a lot into MPG depending on how he drives. You can always be more lean on a daily driver than you can on a car that you are going to beat the snot out of, so keep that in mind as well. Just be sure to let him know this in advance :)
Che70velle
02-13-2015, 08:40 PM
Just my opinion, but I think you would be money (or fuel mileage) ahead doing a 5.3 over a 4.8. I know my foot stays further on the floor to get and keep the 4.8 in my work truck moving more so then my wife's Tahoe or my old personal truck with 5.3's in them.
Also the tune can play a lot into MPG depending on how he drives. You can always be more lean on a daily driver than you can on a car that you are going to beat the snot out of, so keep that in mind as well. Just be sure to let him know this in advance :)
Agreed. We purchased a couple of 4.8 work vans in 2005 for the fuel economy. The advertised mpg was higher with the 4.8 option, so instead of going with the 6.0 liter vans, which were the same price by the way at the time, we opted for fuel economy. BIG mistake. I have to keep my foot in the gas way more to keep the van up to speed, which kills my mileage. Flat ground is ok, but not a lot of that in North Georgia. Lesson learned.
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