How's your MFI fuel mileage?

dtw · 05-26-2003, 07:09 PM

I'm giving strong consideration to turning my #2 restoration project into a daily driver (referring to the '72 MFI T I bought in December, which I'm restoring to essentially stock). The key issue I have realized, is the gas mileage I can expect from a freshly rebuilt 2.4T with MFI (versus Webers).

Simply stated, if it is going to suck too much gas, I'll sell the sucker and dump the proceeds into my monster '72 widebody, which is welcome to suck all the gas it wants.

Tell me about your experiences....I'm not looking for miracles, as I can live with 20+ mpg, I just don't want much less than that. What kind of gas do you give yours? I assume 87 octane is OK, given the ultra-low compression?

John Harmon · 05-26-2003, 07:16 PM

I have a 73T that gets in the low 20 mpg range but I do very little city driving. I've used87 Octane gas for years with no problems.

pwd72s · 05-26-2003, 07:18 PM

The BEST I ever got was 24...following a cop through Utah at 55, during "those" days. Honestly? "72 T with stock everything? Expect an average of 15-19. A lot depends on your driving routes, your driviing habits..

724doorE · 05-26-2003, 07:39 PM

Hi Dave, thanks again for the parts. The best I ever got was maybe 24-25 on a long run. If I'm not mistaken, the original road tests claimed maybe 16 + a little. Now my pump is worn pretty good and it is pumping to a 2.7RS half spec bastard child and I probably get 15+ in town. My pump is way rich and also donates some of its magic petro to the oil sytem

. By the way 87 is indeed just fine for these old cars. The RS pistons are 8.5 to one and I've never had anything near a ping and I'm not known for being gentle.

So, if your city driving is like Chicago where you can be parked for a while and 10 miles takes 45-60 min, then you might not want the T, but if your commute is on a lightly used 45-55 mph through fare I'd say give it a try. You could always sell it if you didn't like it later.

304065 · 05-26-2003, 07:42 PM

Hmm, lemme see here. Lime Rock is 1.53 miles and I completed 25 laps for a total of 38.25 miles and I burned at least 5 gallons of gas, so how about best-case of 7 MPG? WOT probably 80% of the time (but I'm working on it. . . )

dtw · 05-26-2003, 08:14 PM

John, I think I'll designate your data point as an "out-lier"

If I can get over 20, that's my magic number. In-town is not too big of a problem, I just need to be able to get decent mileage on the long trips back and forth to clients. From what you guys are telling me, it sounds like a reasonable expectation.

The thought popped into my head after driving Tim's Flying Turd 2.4T MFI...great fun, but we burned tons-o-gas...I'd guess 10mpg or worse. Though, I know his car has, um, issues right now.

Speaking of which, that T was a blast to drive. Wish I had known they were that rev-happy and fun, I would have bought one years ago.

Paul Thomas · 05-26-2003, 08:39 PM

DO IT DO IT DO IT. You won't regret it. How bad could it be? If it starts to seem bad, come drive my car for a while.

Paul

Tim Walsh · Tim Walsh's Garage

ya I burn a ton of gas with the turd.. I burned another $20+ worth of gas this weekend and didn't go any farther than High point(about 10 miles away). Granted I haven't tuned her well at all, just too much going on with a upcoming trip and moving buildings at work.

I don't think my car is a reprsenative of the general MFI population.

If nothing else I'd bet EFI (megasquirt?) would alot ALOT with this and you'd still have an small displacement early car.

CamB · CamB's Garage

Hahaha. It is funny how bad the fuel economy is. My carb'ed Jag XJ6 still manages 12-14mpg, and I'm a lead foot. I thought that was horrendous.

Ah crap, I just worked out the '69 is only about 16-20mpg (3.2 short stroke, EFI). Who's laughing now

Matt Smith · 05-26-2003, 09:04 PM

Exactly.

most of the heathens who slagg off the mighty 72 T have never even smelt one revving in anger.

I drove mine every day for 2 years or so, in the city too and fro work. I didn't mind at all putting gas into it because, aside from everything else, its fun popping the gas flap open.

Don't expect miracles though. I think the thing that finally sealed the fate of daily driving was the tortuous warm up period, where you can literally smell the unburnt fuel when you come to a rest at the lights. Not good for longevity in my opinion.

Not a good look in front of my colleagues in the work parking lot either, as I work for a company that also researches atmospheric contaminants.

Blaa blaa blaa....buy an SC.....blaa blaa

pwd72s · 05-26-2003, 09:11 PM

Actually, the planet would be much better off if mankind rode bicycles or took mass transit for the longer trips. ALL of mankind. Except, of course, for the elite politicans.

Tim Walsh · Tim Walsh's Garage

just another data point for the FT. I've disconnected the cold start line and she's started great every time without the warm start problems I've been having (dtw, you know what I mean)

I think she's running SOO rich that she's basicly in cold start mode (the stack injectors) all time resulting in my incredibly crummy miliage.