High Gas Mileage Engine Swap Options

[deimox]

I was searching around but had no luck: Are there any common swaps people do in an effort to obtain high gas mileage?

I'm hoping to find a fuel injected, diesel engine that would present itself as a feasible swap. I was also curious about the potential of turbo charging said engine so that some power would be available when needed, while keeping the gas mileage high if kept below boost.

Turbo is optional and any help is appreciated.

Thanks,
Adam

[RallyBob]

I don't know of anyone doing a swap just to increase fuel economy. Most swaps are for the purpose of increasing power and performace. That said, what mileage are you striving for? Assuming you are referring to a GT (you didn't mention the model of Opel you have), then you are already starting with a car with a fairly low CD, and capable of 30-34 mpg with a stock 1.9.
Through attention to detail (narrow high pressure tires, lower ride height, front air dam, flush wheel covers, etc) and an overdrive gearbox, nearly 40 mpg is possible. 40 mpg is very possible with a 1.1 litre GT engine.

I suspect a prepped 1.9 could also attain this mileage, but at a price. Internal engine modifications to enhance mileage could be utilized with the application of modern technology, as the CIH engine is rather antiquated.

Bob

[opelwasp]

i had heard someone was going to try to attempt a Geo Metro 3cyl and a Geo Tracker 5 spd tranny swap into a GT. But have as of yet heard any results. As soon as funds allow I will be trying this myself, but will be adding a EFI turbo from the Canadian version the Pontiac Firefly. I will also be attempting a GT hybrid in the future too.

[PROPEL]

How about 113 mpg?
http://www.rsportscars.com/eng/cars/speedster_eco.asp

Too bad the U.S. won't get Ecotec diesel engines any time soon. Imagine doing a conversion and then running it on vegetable oil. Talk about fuel economy! And it would actually have guts, too.

http://www.findarticles.com/p/articl...33/ai_20021278

[deimox]

Thanks for the replies, just need something to bump me in the right direction. I'll probably end up finding a car with a high gas mileage diesel engine stock, just investigating my options. Thanks again.

Adam

[oldopelguy]

i had heard someone was going to try to attempt a Geo Metro 3cyl and a Geo Tracker 5 spd tranny swap into a GT.

Actually it's a Samurai transmission. I still have all the parts to do it, but the tranny bolt pattern looks like I might be able to put the 5 speed tranny on an Opel 1.1L without too terribly difficult an adapter. Then the entire EFI system, a throttle body type, could be grafted onto the Opel motor. It is a fuel only system, and I think if I use the Samurai 4-cylinder computer with the Metro injector I should be just about right for the 1.1.

This project of mine is on hold until after the new motor goes in the Admiral, which if all goes well will be this weekend. I'll post some pictures/mesurements of the Geo/Suzuki drivetrain combo if anyone's interested.

One option perhaps worth considering would be an actual Opel diesel engine. The later Kadetts had a 1.5L unit, that I think was in the Kadett C so it should be able to be fitted if you can find one in Europe and get it sent here. Otherwise, I'd look for a Chevette diesel. The Isuzu diesel in them is legendary for it's long life (90% of the refrigerated semi trailers use them to drive the compressors) and the Chevette diesels all averaged 45-62mpg. It also helps that they are basicly the same car as ou\r Opels, so there shouldn't be a whole lot of engineering to drop one in.

[GoinManta]

Actually, as an added bonus the chevette diesel came with a 5-speed

I have thought of this conversion in a Manta if gas gets to pricey. I also have a 2nd car to do for my other son.. and was contemplating the suzuki thing as well. This is what I found..

A 94 Suzuki Swift GT had this in it:
Twin cam, 16 valve, Port Fuel Injected, 4 clyinder, 1.3L motor.

Specs:
100 HP @ 6500, 83 Ft/lb @5000
MPG 29/36
Curb weight of the Suzuki was 1951 lb, 2625 lb gross w/ manual.

The 1988 Chevy Sprint had a 1.0L 3cly, single cam, intercooled turbo.

Specs:
70 HP, 107 ft/lb
(YES.. it would seem to be reverse.. but thats the specs I found)

MPG 37/43

Curb Wieght 1620lbs

Looks like with a little work a light 1.3L dual cam (or turbo 1.0L) can easily get a GT in the 40 MPG range. Possibly a Manta too.. without losing any horsepower at all.. possibly with a decent gain (especially on the 4 cly).

Also looking at weights..

The GTs Curb weight is : 2105
The Mantas Curb weight is : 2232

Take the heavier 94' model at 1951 lbs.

The Opel 1.9L wieghs about 275 (according to Bob), the tranny wieghs 75 (Shipped a few). That's 350 lbs. Add alternator, manifolds, etc.. we are looking at about 400 lbs. For the drivetrain.. according to teamswift.net consensous there is the entire drivetrain with accessories wieghs in at around 250 lbs. Lets call it 275 due to the Samuaris tranny.

We save 125 lbs of the front of the Manta/GT, bringing our weight close to that of the Swift. Heck and the swift had A/C, etc.. so that can be added to the engine.

Now gearing.. How much are the larger gears in the Samuari going to affect 0-60? Better or worse?

The trannys ratios:

'94 FWD Tranny in the Swift are 3.41/1.89/1.28/.914/.757

'88 Samuari RWD Tranny 3.65/1.94/1.42/1.0/.795

Since 0-60 in the '94 Swift GT was 9.8 sec, a full sec. faster than a high compression Opel GT (10.8 is what I found) ad the Low compression Mantas were in the 13 range. Wonder what the differences would be with this set up. Anyone able to do the math?

Really thinking about doing it now.. Of course my wife would kill me.

Charles

[GoinManta]

http://cgi.ebay.com/ebaymotors/ws/eB...gory=6468&rd=1

Buying a whole car seems cheaper than getting a Opel engine rebuilt.

This one even has headers and some other mods to the motor...

Hmm... It would be cool to convert my sons Manta.. and the gas mileage would probably be a good thing for a teenager..

I think I need my medication.. I am thinking of getting into another project and have no money for it... Maybe my wife was right and I finished my sons car too soon...

Charles

[GoinManta]

Getting more info..

Tranny to look for is the 1.6L from a Geo tracker 2WD.

Ratios are:
1st 3.65
2nd 1.95
3rd 1.38
4th 1.00
5th 0.86

Can handle the power of the dual cam 1.3B better.

There are also headers and computer chips available for the Suzuki motor. Also you can use Nissan throttle bodies, they bolt on. So supposedly it's VERY easy to get over 125 HP from it and about 100 ft/lbs of torque from this little dynomo.. with only bolt on mods. Which in our GTs and Mantas should be real fun especially since they will be lighter anyway.

BTW see attach power curve of the 13B.. I am thinking this maybe a easier conversion than a V-6 and be more fun to drive since it will be a LOT lighter than the Opel motor making the car more lively.

Can someone do the math on the gear ratios and figure the 0-60, and other things that would change due to it.. Real curious.

Charles

[kwilford]

Charles, I think that the same engine also came in a turbo version...

Dare to dream

[GoinManta]

I looked, I found a factory 16V 1.3L Turbo mentioned in Japan but not the US. Only the 1.0L 3cly as far as I can tell came with it. But I could be wrong.. info is spotty online for these cars.

Charles

[kwilford]

Hmm, you might be right. We had the Chevy Sprint (and Pontiac Firefly) up here with the Turbo, but it might have been the 1.0. So, will THAT fit the Tracker tranny, or will the turbo from the 1.0 fit the 1.3?

[GoinManta]

Dont think the 1.3 16V can handle the 1.0L turbo if I read it correctly. But the Samurai tranny can fit either the 1.0L turbo or the 1.3L 16V DOHC motor.

Charles

[GoinManta]

Ratios are:
1st 3.65
2nd 1.95
3rd 1.38
4th 1.00
5th 0.86

Those are the ratios for the tranny I will use

The 4 speed Opel Manta tranny is geared such:
1st gear - 3.640
2nd gear - 2.120
3rd gear - 1.336
4th gear - 1.00

Use the same std Opel Rear Dif Gear - 3.44

Tires on Manta : 195/60r14

The Swift is set up like so:

1st - 3.41
2nd - 1.89
3rd - 1.28
4th - .914
5th - .757

The final drive gear is 4.10

Tires on Swift : 175/70r14

Assuming wieght and drag coeficents are the same..

The gas mileage of the Suzuki swift setup is : 29 city / 36 highway

0-30 MPH - 2.6 Secs
0-40 MPH - 4.5 Secs
0-50 MPH - 6.3 Secs
0-60 MPH - 8.3 Secs
0-70 MPH - 11.5 Secs
0-80 MPH - 14.6 Secs
1/4 Mile time - 16.6 @ 84.7mph

What could I expect the Mantas preformance to be if I don't modify the engine in any way..

How does that compare to the current gearing.. ?

One more thing to note for anyone thinking of this conversion:
Just found it great site.. BTW Steven won't need those dimensions, but the wieght of the SOHC with all the parts on it would be great, and just for the record the wieght of the 1.0L 3cyl.

http://www.ado13.com/dohczuke/dohc.htm

Wieghts:
DOHC with an automatic tranny flywheel and no manifolds: 133
Samurai Transmission: 53

Total: 186 lbs

Add maybe 14 for misc.. (FI etc..)

You got 200 lbs max... for engine and tranny..

Bare 1.9L is 275 (According to Bob L.), tranny I know to be about 75 from shipping the thing. Thats 350, add 14 for manifolds, and alternator, etc..

Thats 364 ...

Looks like this setup will DEFINATELY lighten the rear by about 150 lbs.. Thats about a 7% total weight loss, if you add a smaller radiator, or AL one at minimum, you can get another few pounds.. Since this will be mostly at the front of the center of gravity, that should really balance the car.. shouldn't it? (Bob..?)

Hmm... I am thinking this will be a really neat winter project. Possibly have it ready for Carlilse next year.

Charles

[RallyBob]

Looks like this setup will DEFINATELY lighten the rear by about 150 lbs.. Thats about a 7% total weight loss, if you add a smaller radiator, or AL one at minimum, you can get another few pounds.. Since this will be mostly at the front of the center of gravity, that should really balance the car.. shouldn't it? (Bob..?)

I assume you mean it will lighten the front of the car....

Assuming 2250 lbs for a Manta and 56% front weight bias (1260 lbs), reducing the engine weight by 150 lbs (to 1110 lbs) will drop the total weight to 2100, and change the front bias to about 52%. Should make for a nice handling car I'd think.

[GoinManta]

Yep, I meant lighten the front..

I had a feeling the wieght loss would almost 50/50 the car.. Hmm...

I think I will leave work early and head to the pick-a-part, and see whats available.

So what do you think of the 0-60 times and how the free spinning engine will handle the Opel rear axle gear or the Samurai transmission gears.

Charles

[tom_laan]

what actually costs a gallon of fuel for a high compression opel engine? here it costs € 1,47 for one liter. and 1 euro is like 1,30 us dollar.

and i believe gallon is 4,5 liters wright?

that 1,47 is the recordprice right now. it hasn't been so high ever. and it keep getting worse.

[GoinManta]

Here in the US its $2.25-$2.50 or so a gallon, and also going up.

So a modern 25 City / 30+ MPG option for our older Opels that improves performance and handling, not to mention easily installed and economical A/C for probably under $500 complete is driving me towards this.

Charles

[jlthunder]

Here is a quick conversion off of my Coca Cola can.
12 oz = 355 ml
1 gal = 128 oz
128/12 = 10.667
355 ml * 10.667 = 3790.335 ml/gal or 3.790 liters/gallon.


1.47 euro/liter * 1.30 USD/euro = 1.911 USD/Liter

1.911 USD/Liter * 3.790 liters/gallon = $ 7.24/ per gallon YIKES!!!!

Feel free to check my math.

[Sportwagon75]

Charles - I bought a brand new 1987 Chevy Sprint that finally gave up the ghost after 320,000 miles. That 3 cylinder engine was one of the most remarkable engines I've ever known...as long as you kept RPMs up and kept it in the torque curve. I routinely got 50 mpg on the highway and around 44-45 in town. I had an opportunity to drive the injected/turbo/intercooled version of it just one time. I have to say it was one of the fastest cars I'd ever driven...and I've driven some pretty fast cars. I wish I had one today since they're as rare as hens teeth. Today I own the newer version of the same car (Geo Metro) and it sux compared to that Chevy Sprint.