I can't seem finding through google a definite answer. What is the capacity of my 1970 gas tank. I've seen anywhere from 15-21, and also depending on the motor size. It originally came with an I6. Thanks in advance.

 

Run your car til it's out of gas and see how much it takes to fill it.

 

Same as my '71, the factory manual I have for mine says 15 gallons. I've never run it out to check, but I have no reason to doubt the manual.

 

I wanted to know so I can plan a trip.

 

Well, I just looked in my original owners manual for my 70 Camaro and it lists the tank as 20.5 gallons. Don't know for sure. BUT, I do know for sure that when it runs out of gas it will take 19.2 gallons to fill it at that point. So, my guess is it holds 20.5, but can only get 19.2 gallons out.

 

I was going from memory, so went to check the manual from my '71. It actually says it's a 17.0 gal. tank. I've never gotten over 15 gal. in it, and that's why I thought the size was 15 gal.
Seems odd the '70 tank is larger at 20.5 gal. ????

 

Well the most I put into it was 12.9 gallons and had less than an 1/8th of a tank left, so i can't forsee it being over 15 gallons myself. Thanks for the replies, can't wait to find out how my gas mileage was in it!

 

19.7 mpg with an eight tank worth of miles left. 20mpg on the interstate at speeds of about 75 mph. I'm pretty sure I could get a good 23mpg if I was easier on it. Not bad for this ol 350! Hubby got way worse in the 305 TA. Not even 15!

 

The old 350's can get decent mileage if they are well tuned and driven carefully. My '69 Suburban 350 gets a tad over 15mpg around town, and just over 20mpg on the freeway cruising.