Loss of HP with AC on.

[buckeyebronco]

So, now that gas is almost 4.00 a gallonI have really been thinking about fuel milage. I know it is kind of late but I am getting paid to drive for my job so I didn't mind, but with gas going up I will sone be losing money instead of making it. I am also in Miami FL so it is not an option to go without AC.

Back to the question. I while ago I seem to remember seeing that a air intake tube from a 460 will create some boost to the motor. Where can I get one of these? Just so you know, I have already opened up the exhaust and I plan on trying to get a 61mm throttle body to get more air in the motor.

Any other ideas on boosting that HP so I get better milage with the AC on?

[b4hntn]

The first thing I did to my 5.8 was the 460 air inlet tube and K & N drop in filter. However, replacing the timing chain set improved things more than it or anything else at 172K miles. Advance the timing to just a very little knock going up long hills then back off slightly. The wires and coil might have helped 1/2 mpg. Pull codes and repair as needed. BTW, I got my 460 inlet tube at Ford dealer $18 but not sure if they still offer them.

[buckeyebronco]

Thanks, don't think I need a new timing chain yet. The motor only has about 75k on it.

[Conanski]

Originally Posted by buckeyebronco

I plan on trying to get a 61mm throttle body to get more air in the motor.?

It's won't help, because that's not where the bottle neck is.

Originally Posted by buckeyebronco

Any other ideas on boosting that HP so I get better milage with the AC on?

First thing you need to understand is that boosting HP alone will hurt fuel milage, instead concentrate on boosting low rpm TQ. The 2 best ways to do this is with a valvetrain upgrades and longtube headers. Unlike shorty headers, longtubes boost low rpm power much like the long runner intake does on these motors. A cam upgrade is the best bang for your buck to fully realize the power the motor is capable of producing, but adding 1.7 rockers to the stock cam will put valve lift close to the 351HO specs. These additions along with a concious effort to avoid reving the motor more than necessary will produce real milage increases, how much will depend upon the truck the motor is pushing around, a heavier truck and auto tranny will do worse than a lighter truck or one with a manual tranny.

[buckeyebronco]

Ok, so what does something like the setup you just described cost? I am obviously looking for a very inexpensive solution, the wife isn't to keen on spending money on this rust bucket.

[helirich]

I think the best bang for your buck is an MSD box. (power and MPG)

[buckeyebronco]

OK, which MSD box would you recomend? Will I need a new coil, distributer, alternator, battery?