Learning about my newly acquired 1970 442 W-30
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Learning about my newly acquired 1970 442 W-30
Am looking for feedback on Gas being used for the high performance 455 motors? I have recently acquired a 1970 442 (455 W-30) Convertible.
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Any feedback on the expected Gas mileage? Thanks in advance for your feedback....Clasy422...
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Any feedback on the expected Gas mileage? Thanks in advance for your feedback....Clasy422...
Vincit qui se vincit
Joined: Aug 2019
Posts: 943
From: SE USA
Your gas mileage is directly proportionate to the number of photos posted, 
please tell us more about your new purchase, and post photos
My ‘71 convertible 4-4-2 (455 /TH400) averages about 12 MPG on 93 pump gas with octane boost.
please tell us more about your new purchase, and post photosMy ‘71 convertible 4-4-2 (455 /TH400) averages about 12 MPG on 93 pump gas with octane boost.
Last edited by vCode442; Mar 10, 2021 at 10:11 PM.
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Joined: Jan 2010
Posts: 6,120
From: central Indiana
Properly tuned, depending on gear ratio, I would expect low to mid teens on the highway. If you have 3.91 gears, obviously the mileage will be worse than if you have the 3.08.
The biggest improvement to economy (assuming everything else is optimized) can be free, and controlled by your right foot.
The people that say the can’t get more than 7-8mpg either need some remedial math lessons, their speedo recalibrated, or need to learn how to drive and tune a car. Probably a combination of all the above!!
The biggest improvement to economy (assuming everything else is optimized) can be free, and controlled by your right foot.
The people that say the can’t get more than 7-8mpg either need some remedial math lessons, their speedo recalibrated, or need to learn how to drive and tune a car. Probably a combination of all the above!!
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Joined: Jun 2014
Posts: 1,666
From: Ft. Wayne, IN
Run the highest octane you can find. 92-93 pump gas will work, but you might have to retard the timing a bit to keep it from pinging or dieseling. My '69 Toro LOVED the 100+ octane race fuel that used to be sold at the pump back in the '80s, but that was probably overkill. If I ran the 92-93 unleaded stuff w/ nominal timing, it would ping slightly and I had to get in the habit of turning off the engine while the trans was still in gear. If you have an MT, you got it easy (just dump the clutch). Octane booster will help too.
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From: eastern MA
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I had a 3.42 rear in my 70 442. Non air car. Heavy right foot? 8-10. Normal driving? 14-ish.
Really I didn't care. I would fill the tank and go chase anyone on the highway. Back and forth at 100 mph plus until the tank was gone. Oohh the old days...
Really I didn't care. I would fill the tank and go chase anyone on the highway. Back and forth at 100 mph plus until the tank was gone. Oohh the old days...
Last edited by no1oldsfan; Mar 11, 2021 at 02:48 PM.
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