In November I bought an '84 Bronco with a broken motor. I replaced the 302 with a rebuilt motor. It's my first 4X4 and my wife & I love it.

It's got a 302 with a 2bbl carb and C6 trans. We get about 10.5 MPG and I'm told this is about right. I installed an Edelbrock 302 EGR intake on the new engine.

Has anyone out there installed a hotter ignition to get better mileage and performance? I'm considering a MSD 6A. Would it be worth the effort and cost?

I live in Northern California so changes to the engine must have EO numbers or it fails the smog checks.

Thanks.

Bruce

 

Im guessing something needs tuning... that what 351W average, the 302 should be around 11-13 around town, and 13-17 on the highway. my friend bronco has a 302 and after beating it through the woods all day it still manages 12 MPG.......

 

That's what I thought we sould get; 12-15 MPG. Does your fried's Bronco have an auto or stick. We have a C6 in ours and it appears to soak-up a lot of power.

The funny thing is, when I got it smogged it ran very clean, so It's not running rich. The engine always seems to be laboring so I wonder if something is dragging, like mis-adjusted brakes or worn wheel bearings. I need to check everything out.

I bought the MSD 6a and will install it this weekend. My goal is to get 15 MPG.

Thanks for the help.

 

First check is free and simple, timing. If you run in the city a lot, advance time a degree or two from stock, highway is opposite (retard).

Next is what should be obvious, the air cleaner. Get rid of the junk like Fram or STP paper filters. If you stick with paper, use the on that looks the crappiest (thinest, light passes thru easiest). Or, take a step up to the K&N filter and grap at least 1 or 2 mpgs and a couple of hp's.

And my final lecture...

Although a 2bbl meters "less" gas typically, it is also less efficient at atomizing the air/fuel mixture. This is especially evident when you driving habits are less than aggressive. You probably won't experience a differential in mpg going from highway to city driving with a 2bbl.
Rear end gear will also play a factor, but as far as the most efficient fuel atomization, is to swap to a 4bbl, but stay away from a factory set up Holley for mpg's. The next best thing to fuel injection is a Carter AFB (aka Edelbrock carbs). Carter Aluminum Four Barrels are nearly mainainence free, and can be hopped up easily if more power is desired (cheap: swap primary and secondary jets, $30: buy a jet kit with metering rods).

One more factor, as a motor "breaks in" its mpg and power will increase, so let at least 5000 to 10000 miles build up before you do any drastic modifications....oh, and don't forget exhaust flow! A little know item; fake duals actually rob horsepower and mpg's on a small block ford motor.

hope that helps. email if you need clarification.

 

 

I installed a MDS 6Al on my 79 Bronco. I doubt you will be able to tell the difference. I doubt you will improve gas mileage much either. You need to be confident at electric wiring to install the box. Don't get me wrong as I said I have an MSD box on 3 of my 5 vehicles and they absolutly work. I'd just probably not ad one for fuel economy on a 4x4 that already runs good and gets double digit gas mileage.

 

Another 17 year old thread.