Post your tricks for fuel mileage on a V8

Big car,big engine,big gas bills.You bought the barge to be cool,so just blast down the hiway in the fast lane and enjoy it.

 

Most of the ones I had in mind have been mentioned.

Personal experiences though, adding an MSD 6a ignition box gained 2mpg. If you're looking for better mileage, I wouldn't put a clutch fan on it, go with an electric fan. It doesn't take power away from the engine like a clutch fan will. Putting a good air filter like a K&N makes a difference in power and fuel economy as well.

All the other good advice I could think of has been stated.

-Aaron

 

Carcraft or Hotrod did a test on fans. They tested everything. They found the best all-around fan was the OEM style clutch fan. I would have some reservations about using only an electric fan to cool down a big block.

 

I had a '72 Eldo for a while and on the road it got 16-18 as a rule. That was during the double nickle years so I very seldom ran any length above 70.

My '72 would have had lower compression than yours stock but given the age of yours that's probably a mute point. The '71 was the last of the good 472s.

 

Less pressure with the right foot on the gas pedal....

 

My Eldorado gets 27-30 at 65MPH consistantly, with 300HP to boot. But it is a Northstar with all kinds of wierd computer EFI ****; once something breaks, it'll cost so much to fix, the good mileage won't mean ****...

 

17" at cruising speed is livin' large! It's a given that cruise control can improve your mileage but a steady foot and keeping an eye on the vacuum gauge will do even better. Any little change in throttle shows up very clearly on the gauge, even when you're not aware of your foot moving.

I had a '72 Suburban with a 402 once with a vac gauge strapped to the column. I learned to keep a real steady foot on the gas and it might pull 15" at 60mph. If a truck pulled into the lane ahead of me it might go up to 16" as I rode along in his draft. It took that much of a load off my engine to maintain the same speed!

 

Get a smaller four barrel, and keep your foot off the pedal.

Oh, what the hell am i saying, its a hotrod, FLOOR IT, PUT IT IN FIRST, AND DRIVE IT LIKE YOU STOLE IT!

 

Inflate your tires to 40 psi. Rides better like that, too. Try it, you'll like it.

 

Bias plies killed my gas mileage compared to radials. I figure if im getting 12 mpg, so what. At least i'm not driving some 4 cyl. *** mobile. When I finally took the EDELBROKE carb and intake off of my car and put the 2bbl Rochester on it, I lost a few mpgs there too. (prolly cause I"m in the gas constantly now.) I figure I'm not driving a '57 Chevy for economy.

I'm wondering if getting away from the clutch fan might free up some mpg. If I had the parts i'd do away with the power steering and brakes too. Thats another way to free up a little bit.

 

I just rebuilt a Y block and put a RV cam in it. I had always heard that it increases MPG and I'll be damned if I didnt go from about 9 to 12 mpg after the rebuild.

 

Just send me one easy payment of $995.95 and I'll send you an entire jar full of gas mile improving O2. This is very similar to what you would find throughout the atmosphere but only here can you find it in one simple, easy to use jar. Simply pour it into your gas tank, your motor oil, your transmission fluid, and even directly down your carburetor or throttle body. This is compatible with diesel and gasoline engines. Each jar contains enough to last you for a whole week. Recommended to refill your vehicle as regularly as possible.

What if you have an electric or steam powered car??? For 3 easy payments of $495.95 you'll receive the special jar of O2 that's specially formulated for electric or steam powered vehicles.

 

Ditto............

 

I have a frequent driver with a race-built honest 600 hp 460 ci BBC. I pull an average of 12 mpg out of it, cruising at 2400 rpm at 70 mph. I'm at 15" of vacuum there. It goes up to 17" of vacuum at 80 mph, but I don't risk that for long.

Engine is 454 bored .030 over, 9.5:1 compression, runs on 87 octane. Rectangle port heads, light weight everything in the top end, solid roller cam, 260* @.050. Victor Jr intake, 1000 cfm carb. Lots of time in the carb and ignition getting it dialed in. Total timing with vac advance is 50*, 38* on mechanical alone. Every orifice in the carb has been modified to suit the engine's demands. Pretty docile considering what it is.

Gas mileage drops significantly when I go to the track.

devin