The Stovebolt Site Forums The Shop Area Engine Shop Gas mileage??

1950 Chevy 216 with 98K on it. Rochester carb. Truck is all original. Burns a quart of oil about every 200 miles. #3 plug fouls about once every 100 miles or so and has to be removed and cleaned up. Runs really well otherwise.

So I filled up tonight and calculated that I’m getting 13.7 mpg. Is that good or just acceptable and I could be doing better?

My '38 216 with the 3.73 rear end get's about that at 55MPH. At 50 I get 15-17.

My stock 49 3100 w/216 w/a Roch B gets about 13mpg and looses about a qt every 250-300 miles. It may burn some but it leaks most of it out.
Try a plug extender in your cyl #3.

What weight oil are you using?

"So I filled up tonight and calculated that I’m getting 13.7 mpg. Is that good or just acceptable and I could be doing better?"

I'd say that's about right. No mention on how the miles were accumulated, but I'd guess low speed country/city driving for short distances.

My 3600 with a .72 5th gear T5 and original 4.57 rear gears and a pretty good condition 216 averaged 16 to 20 mpg on a 1,300 mile trip to Luckenbach Tx last spring. Mileage was really affected by hills and wind. Head wind bad...tail wind very good for mileage.

Good Luck, RonR

13.7 sounds good to me. That's about what I get with my 4.10 rear end.

32vld..... I’m “burning” 30 weight oil, or whatever I find on sale.

Moparguy..... yep, you’re correct. I drive it mostly on weekends and for short trips to Walmart, Home Depot, or Lowe’s. I drive it to Luckenbach and Fredericksburg one or twice a year for fun. Wish I could have met you there when you made the trip last year!

Volfandt.... what is a plug extender and where can I buy one??

Wally.... I’ve got the stock 4:11 rear end. Sounds like everyone is in agreement that 13.7 mph is about right. Might get a bit better on a longer trip out of town with a tail wind!

Thanks everybody.

An old time trick to make a country style version of the extender Volfandt referenced is to take a piece of leather, say a belt. Cut a piece a couple inches long...put a hole in one end that will slip over the porcelain end of the spark plug. Then you could pull the insulated end off the plug wire (careful to not pull off the metal clip) slip the plug wire into a hole you made in the other end of the leather. Now with great care position everything so the end of the plug wire is 1/4" or a bit more from the end of the sparkplug.

Now when #3 plug fires the added resistance caused by the spark jumping the gap will cause the coil to produce a hotter spark, causing the oily plug to fire. Probably.

With a bit of imagination you could do the above using an extended plug wire boot and just pull the wire out a sufficient amount so the spark has to jump a gap. Wouldn't have that old time look though.

Good Luck, RR

Is your vacuum spark advance working?
What temperature thermostat?

Thanks for the directions Moparguy! I understand how they work now.

Thanks for the link Tiny!!

Panic...... yes, my vacuum advance works as far as I know. And to be honest, I don’t know which thermostat I’ve got in there. I assume it’s either a 160 or 180 degree.

[quote=Tiny][quote=Spotbiltxo]

Volfandt.... what is a plug extender and where can I buy one??



Any auto parts store has it , on the shelf with all the other misc.parts , I know I just got one 6 months ago they work but it still will use oil ,

You just won’t have to clean that spark plug as often.🛠

Having to stop the engine, grab the tool bag, take out the plug, clean, and then reinstall it before I can make my trip is beginning to get old. One of those no-foul extenders might just be what the Doctor ordered to make my life easier!!

Or, maybe run a hotter plug?

Dennis

I’m going to try real hard to make it to AutoZone this weekend and pick up one of those extenders. Seems like an economical alternative to a ring job, even if it’s only temporary. Hope they have the right one in stock.

I know of one "Mechanic in a can" that seems to work, Restore. I've used it as per the can instructions on a couple of old wore out v8 pickups and it did slow down oil consumption/smoke. I usually try to put it in at the end of the current oil's life, run it a few hundred miles and then do an oil change. Check it out. It might help you get through the summer till a proper solution can be tackled.

RonR

Ron, thanks for the suggestion. I’ll look cor a can of Restore when I go to AutoZone for the no-foul extender.

My 55 235 gets about 12 to 13 miles per gal. If I run the interstate at 60 to 65 mph it drops to around 10 to 12 mph. I have a 55 2nd and 3.90 rear with 29 inch tires. I also have the overdrive but can not see any difference when using it on the interstate.