Super Six fuel mileage

-
It's definitely something to think about these days.

The pickins are slim around here since the price of scrap hit the ceiling. It took two days of driving from wrecker to wrecker before I finally found a /6 behind a Federated. Bought the whole engine for $50 just so I could have the coveted 1BBL Holley.

I think I'm going to modify a stock one to accept a sideways 2BBL.
 
gtaw said:
It's definitely something to think about these days.

The pickins are slim around here since the price of scrap hit the ceiling. It took two days of driving from wrecker to wrecker before I finally found a /6 behind a Federated. Bought the whole engine for $50 just so I could have the coveted 1BBL Holley.

I think I'm going to modify a stock one to accept a sideways 2BBL.
Click to expand...


I really want to do a EFI set up with MPFI on a slant. which I hope to have again soon. But I do need to find a A833 4 speed with OD.
 
That'd be pretty slick. Going to have to figure something out because the cockeyed monsters are outlasting the available carbs ;)
 
gtaw said:
That'd be pretty slick. Going to have to figure something out because the cockeyed monsters are outlasting the available carbs ;)
Click to expand...

LOL ain't that the truth. If put together properly and the right parts I can see some really good mileage out of these motors in a good light weight car like a Early A Valiant or B'cuda.
 
Between here and SS.org I bet a robust solution could be achieved.

I'm more of a hands-on type of guy so I'm always looking to do things the hard way ;)
 
gtaw said:
Between here and SS.org I bet a robust solution could be achieved.

I'm more of a hands-on type of guy so I'm always looking to do things the hard way ;)
Click to expand...

Yeah Slant6.org is where I have been reading up on a lot of stuff including how to mate a T5 from a 4 or 6 cylinder Mustang but the bad part is a rear gear change will have to be done. Can you think how much fun that /6 will be with EFI and 5 speed?
 
gtaw said:
I like my manuals in the tree :D
Click to expand...

They are fun either way. I learned to drive a manual and had to teach my mom when my dad was in the hospital. I had to tell her when to push the clutch in and I would shift it for her. Poor car didn't stand a chance at least it wasn't a Mopar she would have killed us.
 
Last tank I got 17.9 mpg on mostly interstate travel, looks like I've got a little to do to make that number a little nicer.
 
old tired rebel said:
Yeah Slant6.org is where I have been reading up on a lot of stuff including how to mate a T5 from a 4 or 6 cylinder Mustang but the bad part is a rear gear change will have to be done. Can you think how much fun that /6 will be with EFI and 5 speed?
Click to expand...

A mustang trans will bolt up to a /6?! You have my undevided attention!
 
64Lucy said:
A mustang trans will bolt up to a /6?! You have my undevided attention!
Click to expand...
ok bro u have to look at what u got do u want to have 4 k in that when ur done and it still looks like it do lol .. lets get that thing running then bring that thing over so we can fix the rust and we can paint her if ur going to put a trans in her i would get the newer 904 that we have to go in her
 
64Lucy said:
Dang. I was hoping it would just bolt right up without adapters. : (
Click to expand...

No and you will have to make at least one. Dart_Doctor has the right idea fix what is wrong with it and get it running properly along with a good trans,then you are set. The rest of the repairs will be easier to deal with with it running right.
 
alright Cliff. i found out when changing the diff gasket that Lucy has a 2.93 rear.
 
Well, here's a reply a bit outside the bounds of this topic, but: I've got a 318 w/ a 4spd Mnl in a BCuda Convertible. When I first got the car, I drove it for about 100 miles on I-85 @ abt 60-65mph & got approx 23mpg. That seemed really ridiculously high for this setup, but it seemed to work out. Also, this car had a points ignition & a 4bbl Holley (maybe abt 500cfm - forgot the model #, but it was a smaller 4bbl).

Oh yeah, also the 318 is out of a 1985-86 Fifth Avenue, so it has the newer heads, also good for 'newer' gas.

Later, I changed to electronic ignition & carb to a new Thermoquad. Most of the driving has been City, so the mpg has been around 13-15mpg. I admit that I am not the best at tuning. Nonetheless, a recent Freeway drive for about 200miles again seemed to get me in the 20-23mpg neighnborhood.

I'll admit that a sizable margin of error is possible. But, it seems that a V8 is capable of 15-20mpg if dialed right. I think that that dialing-in might be a bit of luck, but I think my theory that a higher displacement engine that is run at lower capacity (i.e a V8 revving lower than a /6 or 4cyl) can give some decent mpg.

With that in mind, I've always wanted to soup-up a /6 for performance & economy - seems like a lot of potential w/ these motors.
 
stock slant six 225 single barrel carburetor engine in 1970 challenger convertible is about 22-25mpg.

stock slant six 225 with four barrel carburetor 1971 dart 20mpg
 
The 66 slant 6 in my barracuda (also 66 ) got 22.1 mpg which I felt was impressive since there are brand new trucks with modern technology that don't get that mileage. However the truly impressive I didn't find out until I tore the engine down for a rebuild and took the block and head into be inspected. My odometer says 90k but the head was in such horrible shape that the shop said it had more like 190k on it. Head needed 580 bucks just in machine work not including all the parts which was gonna be about 700 total. Ya head was in a bad way so you can imagine how that must have affected mileage and power. Motor in general was in bad shape and yet still put out 22.1. That was also city driving to boot. :) Can't wait to see what it does rebuilt. Only mods was a super six with ported exhaust n intake manifold, hei conversion and 3/4 of the exhaust was 2.25 inch with cherry bomb muffler. Rest is stock. 2.94 rear n 904.
 
Its funny this post is here because thats exactly what I came on here to look for. I have a 69 valiant 4 door 225 with single barrel automatic no clue what it has for a rearend. At any rate this car had sat for almost 4 years before I got it and started driving it about 2 months ago. I have wondered about the gas mileage and just today got to figure it out for the second time....combination rural/intown/highway I got just shy of 26 mpg. I have got these results both times. Stock motor with the same plugs wires it had on it when I got it....im going to do it one more time filled it up today it just doest seem right but the numbers dont lie??
 
Only time will tell. I have had a lot of nea sayers regarding my high number. So, Im going over everything with a fine tooth comb to see whats what.
 
You must log in or register to reply here.
-

Back
Top