Swap options and MPG's.

Problems, ideas and comments specific to engine swaps.
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S15DET
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Re: Swap options and MPG's.

Post by S15DET »

My car (sedan, mostly stock SR20DET, 0.76 OD in 6th gear, 3.54 diff., 205/50-15 tires) commutes at 29 mpg and a best of 37mpg on a highway trip.
510tdi
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Re: Swap options and MPG's.

Post by 510tdi »

Sleepy's-14- Man, I guess my looker was busted. I found your ecotec build. Unbelievable! If I were a farmer like you're a builder I'd be growing pumpkins the size of my house!

Okay fine- The ca18 idea sounds interesting but have many people run these? If I go with a gas engine it would be to utilize more standard practices hopefully reducing X & $ while still making a significant improvement in mileage and performance.

Our driving is probably 70%hwy. The other 30% are excellent driving!

I don't think of this project in terms of cost pay back so if it took a $900 rear end to get the gearing right I'd probably do it. This wouldn't be a total hobby car either. My fun car needs to be my daily. Semi-daily driver really.Thank god I don't have a commute. Actually, it'd be fun if my commute stayed on my local roads. Another reason for this idea is that I'm realizing what a shame it is to live surrounded by scenic twistys and not be able to really enjoy them.

Is this a Prius alternative? I guess it is except with a simple, straight forward, communicative chassis and without the batteries, high-tech numbness or (most importantly) a slush box. The usable room in the goon is good, we've got the '93 Dodge Cummins for the big stuff. Speaking of the Dodge- I've gotten 26 mpg hwy with it and talk about a BRICK! maybe I should just lower it with some coil overs.....

Uber & S15DET- Are you all fairly confident with those mileage numbers' accuracy? 37 mpg sounds great.w
It sounds like gearing really can help .76OD and 3.54 diff gives you what RPMs at 60h?

One good reason to get sick- So I can have time to pick your brains.

Thanks
Sleepys-14
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Re: Swap options and MPG's.

Post by Sleepys-14 »

Thanks 510TDI, also I am willing to bet my engine and trans would be one of the cheapest/horsepower. I have $850 in the engine and trans, tuned ecu was another 200, and then just made the engine and trans mounts, and driveshaft. So I have about 1300 in the whole thing.
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Byron510
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Re: Swap options and MPG's.

Post by Byron510 »

All you gotta do is just.....
Sleepys-14 wrote:Thanks 510TDI, also I am willing to bet my engine and trans would be one of the cheapest/horsepower. I have $850 in the engine and trans, tuned ecu was another 200, and then just made the engine and trans mounts, and driveshaft. So I have about 1300 in the whole thing.
......

And access to about $60 000 in shop equipement :D
And, the most important part - a boat load of experience in modifying cars :D :D

You did however do a fine job, there is no doubt about that.

Byron
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because the opposite never works.
Three B's Racing
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Re: Swap options and MPG's.

Post by Three B's Racing »

dislexicdime wrote:my tan sr20det 510 with a r180 with 336 gears got 30 mpg on the high way and that was with me getting on it and screwing around . philcas1987 also got 30mpg on the same trip with his single cam ka with a r160 rear end with 411 gears
My NA S14 SR20DE with Poncams gets 31-32 high way and 25+_ 3mpg depending on the right foot around town. I'm running a stock SR 5-speed trans with a .82 5th gear 195/60/14 tires and a R160 LSD with 3:70 gearing. Best mpg I've ever seen was 33mpg on the way to Summit Point where I wasn't slowed going over the Shenandoah Mountain range by 18 wheelers or driving 90 + which is hard not to do at 0300 in the morning in the middle of nothing. This is calculated using GPS miles tracking and odometer.
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Byron510
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Re: Swap options and MPG's.

Post by Byron510 »

Man, 33mpg - that's nothing to sneeze at.
The Bronze (2.2LZ Frankenstein motor - 10.5:1, SDS EFI) once did 28 mpg down the I-5 from Vancouver to Portland years ago. And that's with a reasonable street cam, 4.375's on 21" tall 205/60-13's. So really I didn’t have a lot going for me and stil could manage 28 mpg...once. Generally I have my foot in it, and average about 22 on a hwy trip, but have had it as low as 16...

Byron
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because the opposite never works.
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McWicked
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Re: Swap options and MPG's.

Post by McWicked »

Byron510 wrote:Man, 33mpg - that's nothing to sneeze at.
Byron
No kidding. I see that my losing streak remains perfectly intact.

No matter the car. No matter the forum. Everybody gets better MPG than me, makes more HP with the same mods, and runs faster track times. It's weird that it always seems to work out that way...

-McWicked
Go to Heaven for the climate, Hell for the company.
510rob
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Re: Swap options and MPG's.

Post by 510rob »

McWicked wrote:
Byron510 wrote:Man, 33mpg - that's nothing to sneeze at.
Byron
No kidding. I see that my losing streak remains perfectly intact.

No matter the car. No matter the forum. Everybody gets better MPG than me, makes more HP with the same mods, and runs faster track times. It's weird that it always seems to work out that way...

-McWicked
Maybe you forgot to carry the one?
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James
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Re: Swap options and MPG's.

Post by James »

It was my understanding there would be no math…...
Finished is better than perfect......
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okayfine
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Re: Swap options and MPG's.

Post by okayfine »

My SU SR20DE got 25mpg highway at 75mph with the OE 4.375 rear diff gear and 185/60/14 tires. Probably would have done 30mpg with a 3.7.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
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bertvorgon
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Re: Swap options and MPG's.

Post by bertvorgon »

For what it is worth, my 32/36 carb'd turbo 2L+ Frankenstein motor gets close to 25 MPG IMPERIAL, on steady state cruise 75MPH. ( 4,500 RPM )

That is with 4:625 rear gears and 23" tall Toyo R888 tires.

Overall trip averages usually 22 - 23 MPG in real world canyon carving trips. I do run slightly rich with a cruise a/f of around mid 12's.

High 20's to low 30's would be to die for, what with the price of my fuel!
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
Three B's Racing
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Re: Swap options and MPG's.

Post by Three B's Racing »

Such variations with engine combos in mpg. But let's face it fellas, we didn't build it for economy,,,,,,,Did We? Life is like a roll of toilet paper, the closer to the end it gets, the faster it goes, so goes our 510 builds build'm to be fast.

Lou "You don't buy a 4x4 truck for it's economy"
"Lastnight the wife said oh boy when your dead you can't take nothing with you but your soul oh "Think"
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defdes
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Re: Swap options and MPG's.

Post by defdes »

Less MPG = More Smiles. I'd gladly take less for more.
I get about 18 and would never think of complaining.
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okayfine
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Re: Swap options and MPG's.

Post by okayfine »

Three B's Racing wrote:But let's face it fellas, we didn't build it for economy,,,,,,,Did We?
But that's exactly what the OP wants to do.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
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bertvorgon
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Re: Swap options and MPG's.

Post by bertvorgon »

That's right, we don't..... he does.....

When I hit 8,000 in 5th...fuel economy is NOT on my mind..... :lol: :lol:
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan

Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
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