Heavy car, 400hp, and good mileage.. possible?
#1
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Long time reader, first real post (that I recall anyway.)
I just picked up a 1970 Skylark Custom for a whole $1500 to use as my driver to and from school. I've wanted something like this since I was a wee lad, and I'm very excited about the possibilities I have with this car.
My question is about getting good gas mileage (20 mpg would be sufficient), while having about 400rwhp (or else enough to put the beast through the traps at 12-12.99 seconds) and maintaining some great drivability.
It currently has a 383 stroker motor in it that has not been tuned and I sort of doubt it breaking that 20mpg barrier I was hoping for. My idea includes a 5.3L LS swap with some modest bolt on upgrades with a 700r4 to replace what it currently has in it (I assume it's a 350, haven't looked.) I do not know what kind of rear gear it has yet. I assume the car will be about 4000 pounds with me in it.
Any input would be greatly appreciated. I'll be running it as it is for possibly the whole of winter, as I am on a somewhat tight budget for the time being. Thanks in advance, sorry for being so wordy. I'll work on being more concise, haha.
I just picked up a 1970 Skylark Custom for a whole $1500 to use as my driver to and from school. I've wanted something like this since I was a wee lad, and I'm very excited about the possibilities I have with this car.
My question is about getting good gas mileage (20 mpg would be sufficient), while having about 400rwhp (or else enough to put the beast through the traps at 12-12.99 seconds) and maintaining some great drivability.
It currently has a 383 stroker motor in it that has not been tuned and I sort of doubt it breaking that 20mpg barrier I was hoping for. My idea includes a 5.3L LS swap with some modest bolt on upgrades with a 700r4 to replace what it currently has in it (I assume it's a 350, haven't looked.) I do not know what kind of rear gear it has yet. I assume the car will be about 4000 pounds with me in it.
Any input would be greatly appreciated. I'll be running it as it is for possibly the whole of winter, as I am on a somewhat tight budget for the time being. Thanks in advance, sorry for being so wordy. I'll work on being more concise, haha.
#2
On The Tree
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Fuel injected LS engine pushing 400hp will get you that mpg no problem. I have a ls1 camaro with over 400hp and get 28mpg highway. 15city only cause I cant keep my foot out of it. The Key is going to be getting the gearing right to get those engine rpms low while cruising. The 700r4 will help.
#3
TECH Junkie
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400 hp with a 6.0 is easy (see link below), a 5.3 will be tougher and most of the hp increase will be at higher rpm.
If you have to get a trans anyway, you might as well pick up a 4L60 or 4L80 with the motor. They usually onlt charge a couple hundred more. It's getting harder to find low milage motor with cable TB and it's difficult to get a TV cable to work with DBW.
To get good milage, you'll need the OD trans and the correct rear end. If you look at a tahoe, they're well over 4000 lbs and get nearly 20mpg hiway.
http://www.hotrod.com/techarticles/e...#ixzz21ehbAsre
If you have to get a trans anyway, you might as well pick up a 4L60 or 4L80 with the motor. They usually onlt charge a couple hundred more. It's getting harder to find low milage motor with cable TB and it's difficult to get a TV cable to work with DBW.
To get good milage, you'll need the OD trans and the correct rear end. If you look at a tahoe, they're well over 4000 lbs and get nearly 20mpg hiway.
http://www.hotrod.com/techarticles/e...#ixzz21ehbAsre
#5
11 Second Club
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You should be able to do it if you set everything up well.
I have gotten as high as 21mpg with mildly ported heads/cam/intake/full bolt on ls1/4l60e combo in a heavy Chevelle. The car has run a best of 11.92@111.4 mph so far and should have more in it.
Should be 370-400rwhp depending on dyno and such.
I have gotten as high as 21mpg with mildly ported heads/cam/intake/full bolt on ls1/4l60e combo in a heavy Chevelle. The car has run a best of 11.92@111.4 mph so far and should have more in it.
Should be 370-400rwhp depending on dyno and such.
#6
Staging Lane
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No problem. Easy way would be a low boost supercharger setup. The overdrive in the 4l60e will make a huge difference in mileage. Get the right gears in the diff and you'll hit 20 easily.