Gas mileage from a capacitor?

**JoshieDoom** · 08-07-2008, 09:18 PM

Im really really confused on this part... I helped my friend hook up his woofers/amp in his car. He was getting around 34 mpg and when we hooked everything up it went down to 32.2. Its a giant box in a small 1.8l sentra so I figure the shear weight lost his mileage. I hooked up a cap yesterday in the parking lot at work at he got 36.9 all the way home and back with minor fluctuations down and up due to air conditioning/ city driving.

Why?

**310stanger** · 08-07-2008, 09:30 PM

Originally Posted by JoshieDoom

Im really really confused on this part... I helped my friend hook up his woofers/amp in his car. He was getting around 34 mpg and when we hooked everything up it went down to 32.2. Its a giant box in a small 1.8l sentra so I figure the shear weight lost his mileage. I hooked up a cap yesterday in the parking lot at work at he got 36.9 all the way home and back with minor fluctuations down and up due to air conditioning/ city driving.

Why?

im thinking the strain on the electrical system prior to the capacitor actually had something to do with it. why? I theorize that the ignition system could be moderately stronger sans the stereo system, add the stereo and it draws a shit load of current.

**JoshieDoom** · 08-07-2008, 09:35 PM

But he never got above 35 MPG on a coolday with the best of conditions. Now its around 37 in 90 percent humidity and 100 degree heat.

I was BSing about it with a engineer/bracket racer at work about it and he thinks that when the engine is first started the alt charges the cap and when the car needs some more electricity instead of loading the alt it takes it from the cap. Thus less of a load on the engine. I thought about hooking one up straight to the battery of another friends car with just the mileage meter and see if it works....

**310stanger** · 08-07-2008, 09:36 PM

Originally Posted by JoshieDoom

But he never got above 35 MPG on a coolday with the best of conditions. Now its around 37 in 90 percent humidity and 100 degree heat.

I was BSing about it with a engine/bracket racer at work about it and he thinks that when the engine is first started the alt charges the cap and when the car needs some more electricity instead of loading the alt it takes it from the cap. Thus less of a load on the engine. I thought about hooking one up straight to the battery of another friends car with just the mileage meter and see if it works....

admit it, he hired mexicans to push his car

**JoshieDoom** · 08-07-2008, 09:39 PM

Thats creepy as hell we said the same thing today.

**Hot Black Trans-Am** · 08-08-2008, 12:14 AM

I hope he checked for green cards first.

**jd1666** · 08-08-2008, 12:33 AM

**JoshieDoom** · 08-08-2008, 12:36 AM

But in all seriousness why did it increase mileage by THAT much.

Call it BS but it happened.

Im trying to figure out why

**jd1666** · 08-08-2008, 12:38 AM

Originally Posted by JoshieDoom

But in all seriousness why did it increase mileage by THAT much.

Call it BS but it happened.

Im trying to figure out why

maybe he took it out?

**JoshieDoom** · 08-08-2008, 12:55 AM

Took what out?

Before he had a system he was getting around 34. After a system he was getting 32. After the capacitor/system it was 37. WTF

**jd1666** · 08-08-2008, 01:07 AM

Originally Posted by JoshieDoom

Took what out?

Before he had a system he was getting around 34. After a system he was getting 32. After the capacitor/system it was 37. WTF

WELL SHIT I DONT KNOW, thats a damn good question i dont believe it was just that maybe his tires where really low and put ALOT of air into them and didnt make as many stops as he was before i know it cant be from that

**JoshieDoom** · 08-08-2008, 01:19 AM

Negative he didnt do anything. Same stops every day. No driving change. Hes got one of those AVG MPG that changes on the guages

**jd1666** · 08-08-2008, 01:20 AM

Originally Posted by JoshieDoom

Negative he didnt do anything. Same stops every day. No driving change. Hes got one of those AVG MPG that changes on the guages

damn idk i dont see how its possible idk man maybe it works a little bit then

**JoshieDoom** · 08-08-2008, 01:22 AM

EXACTLY

im cumfused

**jd1666** · 08-08-2008, 01:38 AM

haha try it out in your dd (not the t/a) and tell us if it works. im out for tonight peace bro

**JoshieDoom** · 08-08-2008, 01:39 AM

My T/A= My DD

150xxx and going

**Mr. Luos** · 08-08-2008, 09:43 AM

Probably did the math wrong.

**310stanger** · 08-08-2008, 09:46 AM

if it means anything, i wouldnt really rely on the avg mpg calculators on cars. i question how accurate they are, they work off of throttle application and average that out. so if he floored it 5 more times one day then the other it will augment the readings. The only real way to compare would be to see how many miles he went on a tank and divide that by how many gallons the tank is.

**JoshieDoom** · 08-08-2008, 11:25 AM

95% of the driving route is cruise control 70mph parkway.

**ARM5280** · 08-08-2008, 02:42 PM

Look fill the tank up all the way reset the trip meter, drive with capacitor for a few hundred miles. refill the tank divide mileage by gallons. Do the same thing without the cap when you realize it is the same come back here and apologize for wasting our time, go slap whoever gave you the advice about cap being charged less alternator draw bullshit, then go on with your life! Thank You have a nice day.