Hi there
 

Just to introduce myself.

I have a 1969 Buick that I am trying to push the envelope on both HP and MPG. It's a very fun car, but getting MPG on a big 455 motor isn't easy!

So far I've converted to computerized FI, I have a 2.56 rearend, and a few other tricks. Right now, my next step will be getting a custom camshaft ground to be a good compromise between HP and MPG- my current cam probably has too much intake duration for an efficient burn.

In the past I've gotten over 19 MPG (hwy), and the car runs 11's in the 1/4 mile. Not bad for 4300# car. I consistently to break 20 MPG and hit the 10's, which I think is achievable with a bit more work.

Anyhow, I look forward to learning/talking about MPG.

-Bob Cunningham

Hey there, good luck with your build!

Do you drive anything that gets decent mileage for those times you want to be above the teens?

Wewlcome bobc455! HP and FE don't have to be in two completely different cars. Those numbers are respectable for a car that heavy and a motor that big. I'm sure you'll find something here that can help you increase those numbers.

I wonder if you can run two completely separate fuel injection systems - one setup for lean burn with smaller more better vaporizing injectors and another setup for power.

Hows it going Bob? With your FI system wonder if it would be easier to implement some kind of MSD system

Depending on what kind of FI you're running, it might be easiest to have something like MS that can switch between fuel maps on the fly. You can run around town lean, and switch to a richer map at the drags, provided you don't do this already.

11,s with a 2.56 ?

If you dont know anything then I equally don't know anything.

If some doubt that calculator there are many others around , and here are the results of a 4300 car with an 11 second 1/4 mile that I found.

https://www.dsm.org/tools/calchp.htm =639 hp
https://www.dragsource.com/index.php?...s&calctoview=4 =638.5 hp
https://www.greatlakesdragaway.com/in...page=analyzers =635
https://www.4racecars.com/calculators...alculator.html =Your car weighs about 4300 pounds and can complete a 1/4 mile in about 11 seconds. That means that you've got about 638.53 HP at the wheels, and about 830.08 HP at the flywheel.

Of course these are a rough guide but i'me sure you get the idea.

and... he's gone

Maybe he was talking about the 1/8 mile?

I was really hoping I had another land yacht driver on this site, but oh well.