Economy and Performance

[silicon_bronco]

Ok this is a multi part question. I was driving home late one night after work and started to think about a few things. I know that there is a way to get better fuel economy and over all performance out of my 95, 302, 5.0 lt.. Now that I have work I can start on my project. So lets talk about the below items, if you don't mind.

Discussion will be:

1. Performance

2. Fuel economy

3. Modifications

4. Axles

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1. Performance.

Other then the normal tune-up's and up keep, what items could be added to a truck

to get max performance for road and off road. Would going for stronger and more refined parts like wheal bearings, axles, drive shafts, differentials, etc. do any thing for efficiency. I know that you can add any of the above to get performance, but would this also equate to efficiency? What would you do for your truck to get better performance and efficiency? Is is possible to have both?

2. Fuel economy.

General tune-ups, tires, and how fast you drive make a difference on fuel economy.

What els could be done to improve this.

3. Modifications

what would you do to your truck. This is more of a fun question and I have asked this is other post. Sorry for the repeat but I know there is always something new coming in to our minds that we would like do to our trucks.

4. Axles.

Would it be possible to put my Ford 8.8" on the front and put a Dana 60 on the back. What combo are you using or would you like to use on your truck?

I have heard about duel gearing for your truck. One set of gearing for road and one for off road. How would one go about doing this?

thanks all !

 

[bluesman17]

Generally you lose economy when you go for performance. The bigger the rubber your turning the lower the mpg especially if its not regeared.

 

[bew8484]

I say before adding aftermarket performance upgrades make sure your truck is ready to except them. For example All tune ups and fluid changes are current. As far as the modifications part: I just ordered cut out fender flares, and I'm going to 14.5" wide 35's.

Bew8484

 

[83bronco33]

probally depends on the money involved. i would be using all terrain tires not large mudders. wouldnt use biger than 33,s either. everone tells me open air cleaners. your probally would use k&n set up on your rig. aslo headers. make it breath better! ignition upgrades are also the way to go. better spark plugs, larger plug wires, high performance distribtor cap. good luck. i have a 83 full size bronco im considering the same thing. gas here in iowa is currently 2.39 per gal.

 

[wtfdissux]

one real easy way to increase milage is to lighten the load take all the tools spare parts and general unneeded stuff out then look at things like does that spare need to be outside on a large braket or would the smaller inside one work or instead of a winch bumper that you may never need why not a much lighter than stock tubular for example

 

[94redbronco]

one thing no one has talked about if you do put an intake and headers on your truck. you have to do an exaust, a 3" custom would be best. also if you want ANY OF YOUR AFTERMARKET PIECES TO WORK THEY WERE INTENDED then you must have some sort of after market program in your truck. the best thing you could have done would be have a wideband sensor (air/fuel sensor) hooked to you truck on a dyno and have a custom program writen for your truck. now that is expensive but is also the best way to get the most power and best MPG's out of your truck. the cheaper way is to get a chip or self programer. even if your car can take more air in and more air out your car can only ajust so much with a stock program. now this aplies to almost all upgrades heads, cam, bigger fule injectors, etc. hope this helps you get all the power you need.

 

[ocalabronco]

there is some pretty good advice coming your way. but with concern to your axles and gearing and such, if your max tire size is 33's, stick with the factory stuff. you would have an extremely hard time making an 8.8 work up front, because the diff is pretty much in the center of the housing, whereas your stock D44 TTB has the pumpkin and driveshaft far to the drivers side. you could modify the 8.8 to fit, but if you did get it to work, you'd be constantly running on the coast side of the ring and pinion, which is certainly not healthy. then you run into the issue of an 8 lug rear and 5 lug front. a dana 60 rear is serious overkill for 33's. dual gearing? forget it. stick with one set for street and trail. with concern to performance and MPG efficiency, the easiest and most cost effective mods to do are a less restrictive air intake (read:K&N filtercharger or similar filter), less restrictive exhaust (single or dual, jury's still out on which is better), and tweak your timing. if you advance your timing ever so slightly, you can drastically increase your fuel efficiency. there is a member over on Fullsizebronco.com that did all of the above mods, including timing, who is getting 17+ mpg out of a stock height bronco. hope that clears some stuff up

 

[wtfdissux]

if you can remember who it was that did the mods or copy and paste it to my e-mail:[email protected]

that would be great as i am more concerned with better milage than power that is the easy part

 

[ocalabronco]

go over to FSB and register if you arent already a member. once your in, PM a fellow by the name of sixlitre (its spelled just like that, he's canadian). ask him about advancing the timing and he'll hook you up

 

[Seabronc]

i am more concerned with better milage than power that is the easy part

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Another thing that will give you better milage is selecting a rear end gear range thet will keep the engine in the low end of the acceptable cruise RPM range (2000 - 3000 RPM). Power isn't my greatest concern either and that is why I like the 3.08 gears with my 31 in tires. That gives me around 2170 RPM at 65 and on the highway and I get just under 13 MPG, (I let my cruise control drive whenever possible, it is more consistant than I am with the gas). Keep your foot off the throttle, unless you want to stomp a Chevy that is ) .

I have been persuing the same thought line that Silicon brought up in reference to power and economy, (Can you have your cake and eat it too?). I believe the answer is a qualified YES. Manufacturers build most vehicles with an engine designed to make everybody happy and in effect they make the people on the two ends, ( Economy and Power), both unhappy. But then all us discontents have to do is to decide how you want to use the truck, come up with a plan, and stick to the plan.

There are more things that can be done with carborated engines like mine to improve economy, (none of which I have done yet, but am about to embark on), like timing, adjusting the mechanical advance on the distributor, and fine tuning the carborator (smaller jets but enlarging the power valve channel restrictions, fine tunning when the Power Valve kicks in, adjusting when the secondaries come into play, etc.).

One thing that was mentioned by wtfdissucks, is lighten the load, (put your Bronco on a diet), which gives you an effective power gain by reducing the weight to HP ratio, replace metal with fiberglass where ever possible. An electric fan system vs mechanical leaves the horse power for the wheels instead of slinging blades. Then there is the electric water pump which does the same thing. When doing things that actually boosts the HP of the engine you may run into emissions law problems and start chewing on the economy end, but that can be balanced with some of the other items previously mentioned in this post and in some of the other posts to this thread.

The bottom line is, there are a lot of things you can do to improve economy and some of them come at no sacrifice to power.

My engine goal is:

1. shoot for 20+ MPG

2. boost the HP to the wheels

3. keep it emissions legal

That's my .02 and I'm sticking with it :-"

Good luck,

>-

 

[wtfdissux]

this is a reprint from the converation i had with sixlitre at fsb in case any one else wanted to know:

it got faster and faster, I ***** you not. You can have your cake and eat it too. In a nutshell;

1. Ignition; Great aftermarket plug wires, MSD coil, Autolites gapped out to .055, 100% shape cap and rotor, bump timing to 13.5 (vast improvement in mileage and throttle response).

2. Exhaust; Custom built 2 1/4" headpipes into Flowmaster Y-pipe, exiting at 3" into 3" cat. From there you can put any exhaust you want on. The improvement comes "cat forward" not cat-back as manufacturers would have you believe ( biggest acceleration improvement I've ever got from a mod and a solid 2-3mpg imrovement).

3. Chasis; stock sized tires to max inflation, brakes checked for drag, synthetic wheel bearing grease, axle fluid and transfer case ATF too.

That's the jist of it. Sure there's a K&N filter but that never added anything truly measurable, though it probably helped other mods. I also added shorty header but they too only helped acceleration, not mileage.

You cannot believe how much power and mileage is robbed by the stock Y-pipe and cats. The igintion you can do this weekend and will likely pay back in a month with gas priced where it is. Storing your 35s and going back to stock sized tires will give you back 2-4mpg tomorrow too.

That's it in a nutshell. Get the coil, re-gap the plugs, bump the timing and go for a better exhaust, it will pay off.

Just to be perfectly honest I've recently stopped using the Bronco as a daily driver and switched to a 1990 Town Car.

By EPA ratings alone it gets 42% better mileage and I'm playing with the motor right now to improve even that.

 

[Seabronc]

Thanks wtfdissux! Glad to see that some other people agree that the Bronco can be made more economical and powerful at the same time /emoticons/[email protected] 2x" width="20" height="20" /> .

>-

 

[wtfdissux]

what i have been thinking about is on the trucks that have really tall gears for large tires if you switch to a closer to normal size without changing gears how will it afect your mpg(have to change speedo to be sure) for example i run 31x 10.5 with 3:56 gears wich is better for mpg mine or lower like on your truck just something i have been pondering as my ideal is to swap wheels and tires for my weekenders without much else t change

 

[Seabronc]

what i have been thinking about is on the trucks that have really tall gears for large tires if you switch to a closer to normal size without changing gears how will it afect your mpg(have to change speedo to be sure) for example i run 31x 10.5 with 3:56 gears wich is better for mpg mine or lower like on your truck just something i have been pondering as my ideal is to swap wheels and tires for my weekenders without much else t change

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That is why I like the 31 x 10.5 with 3.08, it keeps the cruise RPM down. I cruise at 65 so 31's with 3.08 puts my cruise RPm at about 2170 RPM, with 3.56 the RPM would be around 2550. I would like to go back to 33's next time around so gers in the 3.5 range would be better for the way I operate the truck. That is why keeping an eye on what the "tire size/ gearing / normal cruise" is important. You need to know where that puts you in the acceptable cruise RPM range. For example if you normally cruise at 55 you would be turning around 2100 with 3.56 gears which is close to the low end of the acceptable cruise speed for a stock Ford engine, and it puts you in the best economy RPM for the tire/gear/cruise speed combination. If you wanted to get a little better performance then 3.73 would be a good combination with 31's at a 60 - 65 highway cruise.

My head is hitting the keyboard.

>-

 

[killerbronco666]

buy a honda for fuel economy keep the bronco for fun. /emoticons/[email protected] 2x" width="20" height="20" /> /emoticons/[email protected] 2x" width="20" height="20" />

 

[cowboydan]

for economy/ emissions = propane

preformance= k&n, headers with 2.5" exaust, edlbrock preformer intake manifold

mods= 4" lift, 33/12.5 mud

axles= straight axle conversion dana44, 9" rear, 3:73 gears posi, as your t-case has a gear reduction in low range

 

[Seabronc]

Well I have started on the modifications. First was the electric fan conversion. I have a 561 rdiator on my truck which is about as big as they get for stock radiators. It is actually a HD 3 core radiator for a truck with A/C, but I don't have A/C. The fan I am using came from a Lincoln Mark VIII 4.6. It pulls some serious air, 4500 CFM, and is controlled by an Imperial fan control.

The thing here is that you need a alternator upgrade. I originally was going for a 3G conversion but cheaped out and had a 140 Amp alaternator built for me. That is not as good as a 3G but it is handling the extra load 33A with a 100A peak start current for the Lincoln fan. It took a couple of trys at adjusting the on/off temperature before I was comfortable with it. We have had a couple of days in the high 90's and the engine never got above 1/3 scale which is where the big mechanical fan with shroud keep it. It is also more fun working under the hood without that metal blade licking at my elbow. Inside the cab I have a led to let me know when power is applied to the fan and a manual overide switch incase I want to force the fan on. What is amazing is how little it actually has to run after you are up around 35 - 40 MPH even on those hot days.

Soon to come is an electric water pump to get that drag off the engine. From what I have read the electric water pump puts around 25 HP back to the wheels that was wasted slinging water, we'll see. Thus a milage improvement because it doesn't take as much pedal to move the brick down the road.

Comming up also is jetting down my carb a step or two, Holleys are known to run too rich at cruise. Also a complete MSD system including distributor, wires and NKG plugs. Plus, though I am told it may be more work than the benifit is worth, indexing the plugs to improve the burn pattern in the combustion chamber.

That's the news from, "Lake Where'd My Money Go"

 

[mbtech2003]

just food for thought but, my bronco has 3.55 gears and going 75mph i'm turning 2500rpm :blink: prob. because of the overdrive trans. and i'm getting 11-12mpg.(i lost 2mpg by getting the 32" tires rather that the 31's i had before) ( next time i need tires i will get the 31's again

i just retested the rpm speed again my mistake i'm only at 2000 rpm at 75mph

whoops b-(

 

[cowboydan]

big tires take more power to turn