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INCREASED MPG

AVY14

Full Member
Joined
Aug 10, 2004
Messages
1,315
Location
BAY AREA, CALIFORNIA
hey everybody... i just wna share with you guys the mods that i did and it showed me better mpg... i replaced my air filter with the new FRAM AIR HOG but didnt do everything... i did not really feel any changes when i did that mod... then 2 weeks ago i changed my single exhaust into dual with flowmaster 40 and 2 4" tips... after those 2 mods... i felt a great horsepower gain and definitely improved my gas mileage... im usually going for $70 for 2 weeks of gas but now im going like $55... that is a big difference for me... im going to L.A. this week so im gna keep you guys posted of my total MPG... hope it helps some of you guys!!!
 
Yea, I HAD a significant jump in gas mileage after installing a K&N cold air intake. Then got a Flowmaster 50 w/ duals that sounds so good when accelerating, my mileage went back to 16 ...
 
Do you have any other data, like MPG before and after the mods? It helps to have complete data points least wise how can you actual compute the cost savings, and when you achieve ROI on the captial outlay.

I was looking into the MuffMan Flowmaster set up recently. I priced it locally and determined I would need 50 fill ups to achieve ROI with a 2 MPG increase per fill up.

So I would be interested in your data points for a more precise ROI calculation.

Okay thanks so much, Now for Homework review pages 120-130, and complete the Quiz on page 131.

Dan
 
well the outcome of these experiments were just for these past 2 weeks... the real test is going to be this friday when im going to L.A.... when i went to L.A. last time i averaged around 17-18 mpg...

another big difference that i've encountered is that when i accelerate then let go of the gas, the speed doesn't decrease that much anymore and i noticed that i brake MORE often now...
 
results are in... i averaged 20-22 mpg from san francisco to L.A. and that is in cruise control at 88 MPH

I AM VERY HAPPY WITH THE RESULTS!!!
 
I have also seen a big change in my mileage since the Volant air system anf the Flowmaster 50 series w/duals out.

Gary

:)
 
Dandaman said:
Did you do a split after the catalytic converter or a true dual exhaust?

If you look under there, we have 2 catalyic converters now. You can run true duals if you want but a lot of folks say that you need the back pressure that the single provides or you will loose torque.

Butch
 
I drove from Houston to Ruidoso, New Mexico last week and did a little experiemnt on my new 04. I drove the out there with the stock air filter, cruise set at about 80 and averaged around 15 mpg. Which I guess is not too bad being that it had on 4K on the engine, I was loaded down, had a full bike rack, and was going through the west texas "mountains". However, whe I got there I dropped in the K&N replacement filter. It was much louder when accelerating up the New Mexico mountains in Ruidoso, but I averaged 17.5 while there, and 17.25 on the way home doing 80 again. That is not a bad improvement for such a small investment. I am eager to see what kind of mileage I can get on flat highway, rather than the hills.

One other thing I noticed, the 85 Octane regular that they sell in NM is crap. I use 87 here, and put in the 88 when I filled up in Ruidoso. That made a huge difference. Maybe it is the altitude and lower oxygen concentration that makes the difference there. The town is about 7K ft in elevation.
 
TO INCREASE YOU GAS MILEAGE EVEN MORE SWITCH TO AMSOIL, I WILL INCREASE TO ABOUT 5-10 GALLONS A TANK FULL,AND ALSO A 2500 MILE OR ONE YEAR CHANGE.ASK ME HOW JUST PUT IT IN MY 2500 AV,AND I LOVE IT, I MEED ALL THE HELP WITH GAS MILEAGE ON THAT
 
Howdy ;D,
Allright Kid, you have definately convinced me it's time to get some performance mods. I was just wondering how much your current set-up costs in regards to the altered intake and exhaust. Also do you have any idea as to what the actuall horsepower and gas milege gainis versus the actual tourqe loss?
 
zulustyle said:
Howdy ;D,
Allright Kid, you have definately convinced me it's time to get some performance mods. I was just wondering how much your current set-up costs in regards to the altered intake and exhaust. Also do you have any idea as to what the actuall horsepower and gas milege gainis versus the actual tourqe loss?

well all in all i have spent around $420=$$50 for the fram air hog and $369 for the exhaust system (with tax) flowmaster 1 in 2 out with 4 inch chrome tips...i have not dynoed (SP) my avy but just the feel of it... it added a fair amount of hp... i can also feel the avy breathing easier now... when i went to L.A. highway 5 is a steep hill that runs probably for 5-10 miles (GRAPEVINE correct me if im wrong) and with the new mods... it took it like it was nothing (85MPH)...
 
Chevalanche said:
I bought the high capacity filter from the GM dealership and I noticed a difference.
Chevalanche, do you have the part number? Do I just ask for it in the service department? How much was it?
 
In regards to the gains experienced I have something of interest to add.

I just got my 04 AV Z71 (5.3) this week. I traded in a 2500 HD (6.0) in which I had the K&N drop in filter and dual exhaust. Now in the HD you had to have 2 flowmasters that came off of the split after the cat. That thing had pert near 6" of outlet exhaust - it was damn loud too. Hint: Get a 3 chamber flowmaster to prevent overbearing cab noise as with the 2 chambers. The 3 chamber has a deep sporty sound, but is not overbearing - had it on my 99 GMC (5.3).

Now for the meat: I realized while running mods through my head, 30 minutes after driving away from the dealer in my new AV, that I had my K&N still in my HD. Would it fit? I turned around and went back, grabbed my salesman and told him to get a screwdriver. Well it fit just like I had hoped and I had my K&N installed. This took all of 3 mins to swap 'em with he and I working on both, so I was back on the road quick. I had originally thought that the throttle to ground response was due to me leaving 4.10 gears and the 6.0 for the 3.73 and the 5.3, but this was a big difference. Just by dropping the K&N the truck responded like I hoped it would. No dyno results, but I can assure you there is an immediate difference. I am on my first tank of gas, so I dont know what the MPG's are other than when I am running 75mph the comp says I am getting 17-18 mpgs.
As for the flowmaster, I may wake up one morning and decide I want it again, but for now I am enjoying a little quiet after driving the roaring lion for the last couple of years. I must say it did sound bad arse and always turned heads when I went through town. :eek:
 
AVY14 said:
well the outcome of these experiments were just for these past 2 weeks... the real test is going to be this friday when im going to L.A.... when i went to L.A. last time i averaged around 17-18 mpg...

another big difference that i've encountered is that when i accelerate then let go of the gas, the speed doesn't decrease that much anymore and i noticed that i brake MORE often now...
ok
i want part # for this exaust. and how loud is it in the cab.

and where does the exaust end on the truck. i want them on the side like the stock if possable

let me know
thanks
brian
 
I would like to know if this helps your MPG  too
I would like to get better than 17 MPG

Thanks Norm
 
My instant economy has read 17-19mpg on the highway since I bought it 6 weeks ago.

I noticed driving to work this week (1 week after the FM70 install) that my instant economy is reading 19-21 on the highway. We shall see.

I have been calculating mileage at 15.8-16.9 mpgs per tank of gas. I will post the difference when I fill up in the next couple of days.
Would be nice to see anything over 18  :) I have not been able to get 18mpgs with a Z71 since my '94 ext. cab and that was with stock tires on it.
I do have the K&N drop in as well.

Steamer :0:
 
I just had the FM70 installed 2 weeks ago. Single in dual out.  Noise level in cab is not much louder than stock.  sounds awesome outside.  ;D
 
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