What is your avg. MPG with a 350 eng and is it rebuilt?

I'm getting about 14 and it has either 154k or 254k miles on it.

Carb and the ratio of your rear end can make a difference. Higher ratio rear end will get you higher RPM's at cruising speeds thus could use more gas.
If you have a high cfm carb that will be part of it as well. If it's a Holley carb it loves gas like no other.

I have a 350HO 4sp with a 850cfm carter thermoquad with small primaries and large secondaries. I also have a 3:73 (or close to that) safety-track rear end. I have been able to get about 25mi/imp gal on the highway at 70mph @3000 rpm. imp Gals are slightly larger than US Gal.

But if you hammer it you can watch the gauge move to Empty in real time!

The carb is not stock but he has more power and better mpg than the Quadrajet. However, I'm moving it all back to stock and just drive slower.

Thanks. Why are you going back to stock? For shows or resale?

Back in the 80's the thing to do was to make your ride unique and fast. Now it's go total stock...which is better resale.

My LeMans currently has it's original 326 w/62k original miles. It currently has an alluminum intake and an Edlebrock 1406 mounted on it. When I had the 2-speed auto trans w/ the original 2.56 open rear I was getting 20.5mpg. Not that I have done the 4-speed swap, much to my surprise I am now getting 22.75mpg! I can not beleive these old cars can get such excellent gas milage, it blows my mind!

IMO it's almost always a safe bet going as close to stock as you can. Otherwise, when it comes time to sell, you narrow your potential market considerably the further from stock you go. That's why when I see someone say "it's my car I'll do it the way I want to", yes true, BUT, in the event you want to or worse yet, NEED to sell, it may take some time to do so. All of a sudden the "it's my car I'll do what I want to it" can come back in bite you really quick.

Again, this is only my opinion, but I have seen it over and over again. I've also seen where people buy a car cheap thinking they can "only put X into it", then, they get into the project, put twice what they expected and then can't afford to finish. In the process, they "did things their way" and now can't sell the project for what they paid for it to begin with.

I always say when people buy a project and put together their estimate as to what it will cost, they should automatically double it or better yet, tripple it. Then, if you think you can't afford the double or tripple estimated cost, don't buy the project in the first place because it's a long haul, TONS of money, TONs of time, TONS of setbacks and dissapointments.

Look on Ebay and you'll see plenty of "custom" built, "I'll build it my way" cars and very often they have zero bids.

Not only did I manage to keep mine stock, but mostly original as well. I get many compliments about that alone. I keep getting offers to buy it, but it's not for sale.

indyblue that is a great looking car! any more photo's?

Wow, another beauty!

Getting about 4-5 mpg from my 350

I should check mileage on mine, but I'd guess 10-12 MPG with either my 326 or 400. The 326 mileage is hurt by the 2-speed trans.

My 350 has #16 heads and a Quadrajet with a mild cam. I get 16 mpg highway with 3.23:1 gears and a TH350.

What about changing to disc brakes or upgrading the carb and keeping the old one? Help or hurt value?

Getting about 4-5 mpg from my 350



I'll bet your average GPM is higher though, grins per mile.

Jeff

Just keep the old stuff around. Unless you plan to sell it to a fanatical purist, the disc brakes could only help the value in my opinion.

I have a rebuilt to stock specs. 350 with a t-5 tranny and 2.78 rear gear. On the highway I get 24/26 mpg. Around town, probably half of that. I'm looking to switch to a 3.08 rear and don't expect the mpg numbers to change much. Fifth gear ratio is .63 so anything below 70 mph in 5th is lugging.