Something different Building for MPG.

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AdamR

AdamR

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I thought this could be an interesting topic. With gas price just about at $4.00 a gallon in CT and my trucking getting about 12mpg I have a feeling if I ever get the Dart together it will probably get better millage then my Dakota.

So if you were to build a car to get great gas millage how would you do it ?
 
AdamR said:
I thought this could be an interesting topic. With gas price just about at $4.00 a gallon in CT and my trucking getting about 12mpg I have a feeling if I ever get the Dart together it will probably get better millage then my Dakota.

So if you were to build a car to get great gas millage how would you do it ?
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/6 with a 4 speed OD trans and 3.23's in a really lite A.
 
crackedback said:
/6 with a 4 speed OD trans and 3.23's in a really lite A.
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Ditto, E or DFI'd /6 with a modified 4-spd OD trans, 2.73s in a Featherlite Duster along with that new aftermarket setup that you manually switch on to cut the fuel to 50% of your cylinders when at cruising speed. I really need to read up on that. It is being developed by a group of investors in SoCal. I know that the technology is all ready being utilized but this is an aftermarket piece for the masses ... supposedly.
 
Hmmm....Good question. 318 with the smallest port heads and combustion chamber I could find. Heads should be iron too. Cam would be roller with no more than 200 degrees of duration @ .050. Aluminum roller rockers to reduce weight and friction. Roller cam bearings. 200 degree thermostat and port fuel injection. Electric fan. Manual transmission and a 2.73 rear gear. Aluminum driveshaft. Synthetic oil in everything.

Fiberglass hood and trunklid. Anything and everything to reduce weight and friction.
 
Rabbit 4 cyl deisel with 5 speed and remove the rear end to save weight. 0 to 60 5 min. Run veg oil mix from left over hamburger and fries.lol
Bruce
 
speedyb-cc said:
Rabbit 4 cyl deisel with 5 speed and 2.76 rear. 0 to 60 5 min. lol
Bruce
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Bruce, we had a '79 diesel Rabbit we bought in Hawaii and shipped it over here to CA. That was a great little car and we were getting anywhere from 48-52 MPG too. That's when the petroleum companies still priced diesel at $.70/gal.
And yes, merging onto the freeway was challenging but I'd still drive it if it were around today.
 
Yea the diesel's are great but the way to go is elec on all four wheels like the German company is doing with the Mini Cooper. Little 2 cly gas engine for spare power and extended range, the elec motors switch to generators when you let off the pedal and recharge the bat, also work as brakes. Pretty slick set up. I've seen some elec motors putting out 250hp, that x4= yee haa!!
Bruce
 
Engine and trans out of 318 out of a 86 cop car. (39K miles)
Used the 8 1/4 ear too. Relocated spring perches. 2.73 gears, as I recall.
(600 dollars for the Diplomat)
Got rid of the electronic Q jet and re-jeted a junk yard Q jet on the lean side.
Running cop rims (215/70R15)
Stock exhaust. (single)
23 mpg highway when I checked.
Can't bring myself to go to hedders.
No time and more trouble.
 
I know this is brand X but I just bought a '96 s10 2.2L 5 speed and am going to turbo it (not for performance but economy). The turbocharger is the best way to utilize some extra free HP. I have talked to guys who claim to get 34+MPG with this combo and I need something better than my Z71 that gets a whopping 16 MPG for parts hauling.
 
I would probably fasten a 2X4 under my gas pedal, that's the only way I'm gonna get true economy :thumrigh:
 
My 360 powered 68 Barracuda is getting 17-18 mpg around town and 22-23 mpg on the hiway, the same as my v6 powered 4x4 Dakota pick-up. It's also the same mileage I got when the Barracuda had the hotrod \6 in it.

The engine is a 10.6:1, magnum headed LA360 with a Comp XE268 cam, crosswind dual plane, 670 Street Avenger, headers, A833OD and 3.55 gears. The car gets this mileage while still running very traction limited 13.7 sec @ 102 mph quarters. This equates to approximately 370 HP.
 
Dave, Your motor is very close to min. Only difference is mine has worked 302 heads with 1.88/1.60 valves instead of the Magnums and currently has a torker intake. Im still up in the air with what intake/carb Im going to run and if Im going with Headers or manifolds.

What year is your Dakota ? Mines a 98 Sport, club cab with 391s and 31X10.5-15s, 3.9L auto. The millage is no were near as good as yours.
 
When I start putting the wifes cuda back together I'm thinking of going with fuel injection on the 340 I'm dropping in, and maybe swap the 3.73's for a 3.55 or 3.23
 
speedyb-cc said:
Yea the diesel's are great but the way to go is elec on all four wheels like the German company is doing with the Mini Cooper. Little 2 cly gas engine for spare power and extended range, the elec motors switch to generators when you let off the pedal and recharge the bat, also work as brakes. Pretty slick set up. I've seen some elec motors putting out 250hp, that x4= yee haa!!
Bruce
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Just thought I'd interject something here since I worked for Hyster forklifts for 11 yrs. and about 50% of the lifts I worked on were electric powered so I had allot of factory training on the subject. The power is great as Speedy said but I don't think 4 250 hp motors would fit into a car. One possibly driving a conventional rear axle. A 250 hp motor is HUGE. The only thing I can say negative about them is the part about them recharging the battery when you let off the gas. It's a bunch of hogwash. It does but it is such a minute amount it don't even affect things. We calculated the charge put back into a battery after a normal 8 hr. shift (the average run time of a forklift battery before it needs recharged). It came out to be replacing approx. .1% of the charge used in the 8 hr shift. It does work good as a brake though. That's it's main benefit. This technology is called regenerative braking. If it weren't for the size and mass (and price) of the batteries I'd build a electric car.
 
Ah, here's something I'm planning out too. I'm shooting for a build that is almost exactly the same as dgc333's, but with a little more work done to the heads and a few different parts (but with same compression and basic drivetrain setup). First off instead of the COMP cam, I'm going with a Hughes HEH1928AL (less duration, same or more lift I'm not sure). I'm also going to put a LOT of time and effort into cylinder head porting and combustion chamber edge-radiusing. For the top end I'm going to go with an Edelbrock RPM Air-Gap intake and Thunder Series AVS carb, and an Overdrive 4-speed with the Passon Hemi Overdrive gearset and a 3.55:1 rear. Heck, if dgc333 can get 23 MPG in his slightly-heavier Barracuda with less work than this, then I sure as hell can get 25 in my 3000-lb. '70 Duster with a bit more time and money put into the engine (those tranny gears are going to be a PAIN to save up for though...).
 
AdamЯ;254797 said:
Dave, Your motor is very close to min. Only difference is mine has worked 302 heads with 1.88/1.60 valves instead of the Magnums and currently has a torker intake. Im still up in the air with what intake/carb Im going to run and if Im going with Headers or manifolds.

What year is your Dakota ? Mines a 98 Sport, club cab with 391s and 31X10.5-15s, 3.9L auto. The millage is no were near as good as yours.
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Mine is a 99 Dakota SLT, Club Cab, 4x4 with the offroad package which includes the 3.92 gears and 31x10.5-15's and I have the 3.9 v6 auto.

I have made a few mods to improve perfromance and economy.
1. The single biggest improvement was taking the snorkel off the air box and running a piece of 4" flexable hose through the core support next to the radiator and using a K&N air filter in the stock box. This provides a true cold air intake. Tried one of those e-bag systems with the cone filter but it just sucked hot air from under the hood and was worse than the stock setup.
2. I relocated the inlet air temp sensor from the side of the manifold to the air hose into the throttle body. The truck used to get real sluggish on hot days due to temperature soak of the sensor. Now it is less impacted and provides the ecm a signal more representative of the air coming into the engine.
3. I have been using a cat back exhaust on the truck for the past 6 years. The flowmaster system finally rusted out and I just replaced it a couple of weeks ago with a Dynomax System. Even though the pipes in and out of the muffler are 2.5" in diameter from the factory the stock muffler necks down to less than 2" inside.
4. Synthetic fluids in the both diffs and the transfer case.
5. I still run 31x10.5 tires but I use ones with a street tread. My only off road driving is on the beach and a street tread actually works better than an all terrain tread on sand. I will need to get tires again before next winter and I think this time I will get 265/75-15's. These are esentially the same size but there are more choices in street oriented tread patterns.
 
MOPEkidD-3 said:
Heck, if dgc333 can get 23 MPG in his slightly-heavier Barracuda with less work than this, then I sure as hell can get 25 in my 3000-lb. '70 Duster with a bit more time and money put into the engine (those tranny gears are going to be a PAIN to save up for though...).
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Weight difference is a marginal gain at best, but helpful and in the right direction. A smaller cam is also helpful.
 
Don't rule out turbocharging in any of the projects. The hidden benefit to turbos, beyond the force feed power when WOT, is the heat. Most run some type of cooler, to bring temperatures down to reasonable levels. It frequently does not get it below ambient. The additional heat better atomizes the fuel, for a more complete and efficient combustion. To compliment the turbo, alky or water injection. The alky has a side benefit in addition to the cooling, which is alcohol burns. SO if setup right, the alky can replace some of the fuel, further increasing efficiency. With the price of gas right now, a separate "bottle" of rubbing alcohol, for .79 cents that helps defer gas at 3-4 bucks a gallon, over hundreds of miles, is a excellent trade off.
 
My /6 build:
Stock slant 6. The 7.5 compression is begging for a turbo. An appropriately sized turbo, blow through on a small 2 bbl Holley carb. A well designed exhaust with minimal restriction, built for velocity, with a straight through muffler design. I would run some version of a 4 bbl intake, and port match to the head. The head would get a basic port job, premium valve job, and either a port matched intake, OR a shorty, basic tube header, for maximum flow velocity to retain the heat. Synthetic oil throughout, and (GASP) 4 wheel drum brakes (no drag) with sythetic grease.
Rear gears would be matched to tire diameter, and matched to overall goal. Highway MPG would get tall gears at expense of around town drive-ablity, and around town MPG would get a shorter gear, for better torque production.
 
I think electric motor, with built in magneto for charging is the way of the future. imo, also plan on e-85 becoming more widespread in the future.
 
I have a friend that built a 46? Plymouth coupe into a pro streeter. B5 blue,
tubbed etc. He put in a slant 6 and a 833-od. I don't know what gear he had in his narrowed 8-3/4 but he got 27mpg on the highway. That's economy!
toolmanmike
 
Adam i know this is to easy but my sons 04 srt-4 28 mpg. with 7.83 1/8 mile timeslips no brand X's all mopar in this house
 
I would slap a 4BT 4 cylinder Cummins or even a 6BT P-pump and run home made bio diesel!!! A friend of mine makes 586hp in a 96 4x4 3500 on home made fuel. He gets his oil for free from a few restaurants.
 
How about a late 318 roller motor with super light rod/pistons, maybe 9.5:1 cr. The pistons should be coated and you could use clevite h series coated rod and main bearings. The cam would get durabond coated bearings, it would be a low rpm high vacuum type with low valve spring pressure and aluminum rockers. Top it off with a set of 273 heads and the old offy dual plane intake. Use the 833 O/D trans and a 3:23 rear... Stuff that puppy in a 2800 lb car...what do you figure it would do??
 
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