Will bumping my timing increase mileage?

[deepsleep]

I read in the HO faq that bad timing will give bad gas mileage. Does advancing it give better mileage? What about any of the other HO upgrades? Do any of them increase mileage? I spend close to 200 dollars a month on gas right now and even a two mpg increase will save me about 20 bucks a month. So for a 2 mpg increase, I would be willing to spend 200 dollars as it would pay itself off in one year.

I'll need to replace the belt soon too so I can do few things at once and can start keeping an eye out for a good deals on parts as the economy is shit right now over here.

[johnunit]

The HO swap usually gives some mileage boost. 2-4mpg is what I've heard, but it varies a lot between cars.

"bad" timing can mean too retarded or too advanced. The odds are your car is set with a degree or two of as advanced as it will go without requiring premium fuel to run properly. Unless someone has adjusted the timing incorrectly, you probably don't have much room for improvement as far as your ignition timing and fuel mileage.

[cld783]

it's hard to say, if you advance the timing you may have to run premium gas which will cost you more money.. best thing you can do is make sure its got a recent tune up...

I'd also suggest using 89 vs 87 octane even though it costs a few cents more. I get drastically better mileage with it according to my tripminder.

[Lincolnmania]

i run all my cars on 87 octane fuel........bump it up to 12 and if it's good, try 14
every 302 is different......some like more timing, and some dont
my towny i have the timing set to 16 degrees.....no pinging
my vic is at 12 deg.....pings a little at wot
the mk7 is at 12 deg......no pinging

[pvillese]

If you can pick up a used MSD multi-spark box for cheap(I think I got mine off CL for under $60) that will get you a mile or two per gallon more. I was also told that if you can pick up a broken box for free or extremely cheap that MSD will send you a refurbished one or repair yours cheap if you send the broken one in. Also everyone I've talked to that has a tornado on a bigger engine said they instantly noticed a gas mileage increase. I've always noticed an increase in mpg with K&N air filters and they said they have done tons of testing and if it is oiled properly it will not hurt the MAF sensor like some claim. I've also never had one mess up a MAF.

[gadget73]

My car pings lightly at stock timing. They're cranky machines for sure.

You can try bumping the timing up. I don't know that it will help, but it probably won't hurt. Since you drive in mountains and need exhaust work, dual exhaust would give you some gains in power, and as a result a bit better economy.

[85crownHPP]

My 85 used to ping like crazy at 8 degrees and on premium fuel, lol... after I did the sefi conversion I moved it to 16 and it doesn't ping at all on regular. I think the CFI ECM was messed up or something... I didn't pull and reset the dizzy or anything either.

[King_V]

The HO swap usually gives some mileage boost. 2-4mpg is what I've heard, but it varies a lot between cars.

Really? Damn - I'd always assumed it would DECREASE by about 2 MPG with an HO swap, under the theory that:

1 - the extra power doesn't come for free

2 - If the 1987 Mustang gets the same fuel economy as the 1987 boxes, despite being a few hundred pounds lighter.

But hey, if the real-world turns that assumption on its head, then maybe an HO swap is something I should consider down the road... when I have money.

[johnunit]

Really? Damn - I'd always assumed it would DECREASE by about 2 MPG with an HO swap, under the theory that:

1 - the extra power doesn't come for free

2 - If the 1987 Mustang gets the same fuel economy as the 1987 boxes, despite being a few hundred pounds lighter.

But hey, if the real-world turns that assumption on its head, then maybe an HO swap is something I should consider down the road... when I have money.

It's what I've heard, I don't have a lopo OR an HO, so hopefully someone whose done the swap chimes in.

[Outlaw440]

Really? Damn - I'd always assumed it would DECREASE by about 2 MPG with an HO swap, under the theory that:

1 - the extra power doesn't come for free

2 - If the 1987 Mustang gets the same fuel economy as the 1987 boxes, despite being a few hundred pounds lighter.

But hey, if the real-world turns that assumption on its head, then maybe an HO swap is something I should consider down the road... when I have money.

A little ole word called efficiency comes to mind when performance gains and mpg gains are discussed. You don't always necessarily have to sacrifice mpgs to gain horsepower.

[pvillese]

A little ole word called efficiency comes to mind when performance gains and mpg gains are discussed. You don't always necessarily have to sacrifice mpgs to gain horsepower.

A good example of this is the fact that a new Roush mustang gets better gas mileage than the new mustang that Roush starts out with(I think the cobra) and it has something like 300 more hp. They credit it to the added efficiency over the stock setup.

[gadget73]

The HO swap got me 2 mpg, from 14.5 to about 17. It depends on your driving though. If you cruise at 55 in overdrive on the highway and accelerate like Grandma, an HO probably won't gain you anything. If you're pulling hills and actually working the skinny pedal, then more motor may help with the fuel mileage. Of course, the same goes with gearing. A tall rear is great in the midwest cruising the highway, but horrible if you're in the mountains.

[King_V]

A little ole word called efficiency comes to mind when performance gains and mpg gains are discussed. You don't always necessarily have to sacrifice mpgs to gain horsepower.

True enough! The "official" MPG ratings for the 1987 Mustang though are what more heavily threw me on this one.

Now, I have HO swap (but with modern, 21st century aftermarket heads) visions in my head. More power, cleaner burning, more MPG. I love it when win/win is possible...

[Outlaw440]

True enough! The "official" MPG ratings for the 1987 Mustang though are what more heavily threw me on this one.

Now, I have HO swap (but with modern, 21st century aftermarket heads) visions in my head. More power, cleaner burning, more MPG. I love it when win/win is possible...

Ratings have usually seemed a bit screwy to me, like Ford's old '85 Bronco advertisement that toted 27mpg in a 4500 lb 4wheel drive monster, yeah, that gave me some giggles.

As far as the aftermarket heads idea, I will quote an inexpensive daily driver buildup on sbftech currently.

With a stock 5.0L mustang, factory got about 22-23 highway i believe. Added edelbrock performer heads (ported) with a custom camshaft, TFS-R intake with a 90mm tb, 1 3/4" longtubes and added some 3.73's out back. Tuned it with a moates quarterhorse that anyone can buy and use themself. The end result was 27mpg, oh, and a pleasant 350+ hp to go with it.

[1987cp]

With a stock 5.0L mustang, factory got about 22-23 highway i believe. Added edelbrock performer heads (ported) with a custom camshaft, TFS-R intake with a 90mm tb, 1 3/4" longtubes and added some 3.73's out back. Tuned it with a moates quarterhorse that anyone can buy and use themself. The end result was 27mpg, oh, and a pleasant 350+ hp to go with it.

I think I remember reading about that build.