I guess this is along the lines of a question I have...I have the True Flow SAI and I know it allows more air into the intake but if the air has no exit it just kinda sits there and actually winds up using more fuel (to equalize the computers air:fuel ratio). Would just changing the muffler from stock to a more "free flow" style help this or would I have to change the entire exhaust system? As of now I have removed the intake portion of the TF SAI and put the stock back on and have noticed an increase in the fuel efficiency. However I would really like to put the air intake back on so any assistance would be appreciated.
Performance and MPG mods
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I guess this is along the lines of a question I have...I have the True Flow SAI and I know it allows more air into the intake but if the air has no exit it just kinda sits there and actually winds up using more fuel (to equalize the computers air:fuel ratio). Would just changing the muffler from stock to a more "free flow" style help this or would I have to change the entire exhaust system? As of now I have removed the intake portion of the TF SAI and put the stock back on and have noticed an increase in the fuel efficiency. However I would really like to put the air intake back on so any assistance would be appreciated.
ruf455
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In my opinion, you don't need to change the whole system unless you are gunning for some big motor mods or it just kills you that your exhaust is not completely custom. Keep in mind the single exhaust systems in the last gen F body cars. Those cars make more power than we do and they run 3" single all the way back with out notable loss. As our factory systems do, stepping down from 3" to 2.5" out the muffler is a good set up to keep the torque where it needs to be; low in the RPM band. Seriously, unless you are operating in the max RPM range or trying to gain that extra 10th in the quarter mile, I would not bother with a full replacement system. I could be wrong 
Ruf, thanks for the reply. Once again I could be wrong in the thought process that as the amount of air through the intake increases (without an open exhaust) it causes more fuel to be required for the burn, therefore one would need more of a free flowing exhaust to make the most of the AIT mod. I guess I'm hoping to get a more open muffler to compliment the AIT so I can put it back in and hopefully get somewhat of a boost in mpg.
Another question, if dropping from 3" to 2.5" after the muffler keeps the torque in the low RPM band would dropping the pipe to 2" bring the torque even lower in the band?
Another question, if dropping from 3" to 2.5" after the muffler keeps the torque in the low RPM band would dropping the pipe to 2" bring the torque even lower in the band?
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bzbatl
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Once you've reprogrammed your computer, does the Hypertech module stay connected, or can you get rid of it at that point (or possibly get it unlocked and do a friend's?)
bzbatl
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OK, I see it locks to the VIN. Question answered: you have to reset it back to factory to use it on another vehicle.
Here's another stupid question:
Ever since this past summer, my 5.3 pings when using 87 octane. Tried doing tune-up, replaced plugs and wires. I just tried 87 again on this last tank, and it was pinging again this morning on quick acceleration.
I see that that the Hypertech can be configured for 87 octane. Anyone know if this will solve my pinging issue?
Here's another stupid question:
Ever since this past summer, my 5.3 pings when using 87 octane. Tried doing tune-up, replaced plugs and wires. I just tried 87 again on this last tank, and it was pinging again this morning on quick acceleration.
I see that that the Hypertech can be configured for 87 octane. Anyone know if this will solve my pinging issue?
ruf455
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thoguhts from a shade tree...
Search "Sea Foam" on here. Follow the directions on the can. The pinging, if worsening, or, new, can be caused by carbon build up. The carbon build up in the chamber creates an eventual "hot spot". This hot spot can cause unwanted combustion in the chamber (pining). It can also be caused by bad timing, bad knock sensors, etc..however, I would doubt you are having major mechanical issues. Does it ping after the motor warms up? Does it ping when it is cold? I do know that these motors have a history of light detonation from the manufacture. GM considers most of this "normal" if it is light and does not worsen. If yours has just started, or has a heavy sound to it, try the Sea Foam (It's cheap, do it any way, it is worth it)
The Hypertech might sort your truck out as well (remember, I said might). I run the premium fuel tune on 87 octane with out any knock...but it is cold out. This summer, I might have to step up to mid grade or premium.
Lets remember about fuel grades; 87 octane is low in detergent(s). Premium is higher in detergents and will maintain a cleaner combustion chamber over the same mileage as a vehicle that was run with 87. If you drive like me (grandpa) and the motor operates constantly at low low RPM, it will build carbon deposits faster.
Run the Sea Foam, Get the Hypertech (or comparable hand held tune in a box, custom tune, etc), and give your truck the old Italian tune up on the occasion to help keep it cleared out
...
About the higher air flow/more fuel: From what I have been taught, read, etc; Yes, it does cause you to dump more fuel. My GTO suffered with a drop in K&N. I staggered my frequent 7 hour trips with the paper air filter and the K&N (lightly oiled and well cared for). The K&N did worse on MPG every time. The car even felt slower. I put on mufflers, it got better. However, there is a bit of a quirk over in the GTO world where folks aren't getting big gains from CIA's. But that is a different vehicle all together. However, your theory is right. More air in, more fuel added to make up for it....to a point. It is not quite like a carb.
Given a carb adjusted for a certain air and exhaust restriction; you take off the air restriction you foul the plugs with a overly rich mixture. If you put on long tube headers (removing exhaust restriction), you foul the plugs and burn the valves (over time) running a lean mixture. However, if you adjust the carb for the proper fuel demand (now higher with less restriction...i.e. motor needs more fuel to remain at peak efficiency) your power increases and the motor runs strong. Fuel Injection is the same...but..
Our trucks have somewhat of a brain that will work against that kind of sway in the overall performance/tune of the engine. It is built to be able to operate under different atmospheres, different fuel grades, etc (think sea level, to rocky mountains) and adjust accordingly. If you tune your engine (like setting the fuel mixture, etc) you will realize your gains more over, than just putting on the CIA and letting your stock ECU do the work. That said, yes, CIA's help, mufflers/exhaust are a good pairing, and a tune really brings it all together by telling your ECU, "Hey, here is what you do with this new found freedom). With those factors, you have made your motor most the efficient it can be, you'll demand more fuel, make more power, and technically, get better MPG's at a sane speeds now that your power plant is working less to move your rig.
Search "Sea Foam" on here. Follow the directions on the can. The pinging, if worsening, or, new, can be caused by carbon build up. The carbon build up in the chamber creates an eventual "hot spot". This hot spot can cause unwanted combustion in the chamber (pining). It can also be caused by bad timing, bad knock sensors, etc..however, I would doubt you are having major mechanical issues. Does it ping after the motor warms up? Does it ping when it is cold? I do know that these motors have a history of light detonation from the manufacture. GM considers most of this "normal" if it is light and does not worsen. If yours has just started, or has a heavy sound to it, try the Sea Foam (It's cheap, do it any way, it is worth it)
The Hypertech might sort your truck out as well (remember, I said might). I run the premium fuel tune on 87 octane with out any knock...but it is cold out. This summer, I might have to step up to mid grade or premium.
Lets remember about fuel grades; 87 octane is low in detergent(s). Premium is higher in detergents and will maintain a cleaner combustion chamber over the same mileage as a vehicle that was run with 87. If you drive like me (grandpa) and the motor operates constantly at low low RPM, it will build carbon deposits faster.
Run the Sea Foam, Get the Hypertech (or comparable hand held tune in a box, custom tune, etc), and give your truck the old Italian tune up on the occasion to help keep it cleared out
...
About the higher air flow/more fuel: From what I have been taught, read, etc; Yes, it does cause you to dump more fuel. My GTO suffered with a drop in K&N. I staggered my frequent 7 hour trips with the paper air filter and the K&N (lightly oiled and well cared for). The K&N did worse on MPG every time. The car even felt slower. I put on mufflers, it got better. However, there is a bit of a quirk over in the GTO world where folks aren't getting big gains from CIA's. But that is a different vehicle all together. However, your theory is right. More air in, more fuel added to make up for it....to a point. It is not quite like a carb.
Given a carb adjusted for a certain air and exhaust restriction; you take off the air restriction you foul the plugs with a overly rich mixture. If you put on long tube headers (removing exhaust restriction), you foul the plugs and burn the valves (over time) running a lean mixture. However, if you adjust the carb for the proper fuel demand (now higher with less restriction...i.e. motor needs more fuel to remain at peak efficiency) your power increases and the motor runs strong. Fuel Injection is the same...but..
Our trucks have somewhat of a brain that will work against that kind of sway in the overall performance/tune of the engine. It is built to be able to operate under different atmospheres, different fuel grades, etc (think sea level, to rocky mountains) and adjust accordingly. If you tune your engine (like setting the fuel mixture, etc) you will realize your gains more over, than just putting on the CIA and letting your stock ECU do the work. That said, yes, CIA's help, mufflers/exhaust are a good pairing, and a tune really brings it all together by telling your ECU, "Hey, here is what you do with this new found freedom). With those factors, you have made your motor most the efficient it can be, you'll demand more fuel, make more power, and technically, get better MPG's at a sane speeds now that your power plant is working less to move your rig.
bzbatl
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Appreciate the suggestion. I think I'll do that this afternoon. couple of questions, though:
15. Spray Sea Foam Deep Creep into throttle body, fully soaking the blades, the bottom, top, and up and down into the intake manifold behind the throttle body. Use a good amount.
16. Wipe off excess liquid and visible deposits from the throttle body and blades with a shop or paper towel (especially around the edges of the blades), and reconnect intake bellows.
Any pictures on this? I'm not 100% on what these steps are describing.
And the guide on this site says to take it for a spirited drive. Most other sites I googled said to not rev the engine to high rpms until after changing the oil. Any input here?
15. Spray Sea Foam Deep Creep into throttle body, fully soaking the blades, the bottom, top, and up and down into the intake manifold behind the throttle body. Use a good amount.
16. Wipe off excess liquid and visible deposits from the throttle body and blades with a shop or paper towel (especially around the edges of the blades), and reconnect intake bellows.
Any pictures on this? I'm not 100% on what these steps are describing.
And the guide on this site says to take it for a spirited drive. Most other sites I googled said to not rev the engine to high rpms until after changing the oil. Any input here?
ruf455
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Sounds like you are describing TB cleaner. Get a can of Sea Foam Motor Treatment for Gas and Diesel engines. It's a 16oz can of pour able liquid...not a spray like you are describing. Don't fear though, there is nothing wrong with cleaning the TB...most likely needs it. I should have been clearer about which specific SF product. What I am talking about is not a spray. You add it to your intake charge while the vehicle is running (about a 1/3 can) and then another 1/3 into your tank. Next tank, add what is left over. If the directions are NOT clear enough that are on that can, let me know and I will try to get some photos when is clears up outside...kinda nasty.
You take your vehicle for a spirited drive when you are done introducing the product into the intake charge and letting it sit for 10 minutes. It WILL SMOKE, maybe knock and rattle...sometimes scare the hell out of you:mpr: . It clears up.
Don't go putting this in your crank case with out following the directions closely!
You take your vehicle for a spirited drive when you are done introducing the product into the intake charge and letting it sit for 10 minutes. It WILL SMOKE, maybe knock and rattle...sometimes scare the hell out of you:mpr: . It clears up.
Don't go putting this in your crank case with out following the directions closely!
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bzbatl
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Gotcha. Grabbed two cans of it at NAPA for $7.99 each. Also grabbed a 1' section of 3/8 vacuum hose - I assume that's the size of the brake booster vac line?
Now... where's it located, and how do you get 1/3 of it into the intake like that?
I've read multiple warnings about not dipping the hose into the can and letting it suck it out too quickly... so how do you limit the flow (and more importantly, how do you measure off a third of an opaque can?)
The other 2/3 is going into my oil, and the second can is going into the tank.
BTW, as far as instructions on the can - there's two lines of text... not exactly detailed.
Now... where's it located, and how do you get 1/3 of it into the intake like that?
I've read multiple warnings about not dipping the hose into the can and letting it suck it out too quickly... so how do you limit the flow (and more importantly, how do you measure off a third of an opaque can?)
The other 2/3 is going into my oil, and the second can is going into the tank.
BTW, as far as instructions on the can - there's two lines of text... not exactly detailed.
ruf455
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I'll get you some pictures and a short bit of direction in the morning. You should be able to take that hose back, you may not need it. I'll get back in the morning.
Cheers!
Cheers!
bzbatl
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Any update? I got two cans sitting here waiting to smoke out the neighborhood!
ruf455
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Ok, the first photo shows the vacuum hose that attaches to the booster. Remove it and try your best not to butcher the clip holding it on. The hose pulls off easily.
The second photo represent SLOWLY pouring the liquid in to the hose. DO NOT SUBMERSE THE HOSE IN TO THE CAN. You will destroy your motor if it tries to compress a large helping of non compressible fluid. It is easier if you have someone in the truck on the throttle aiding it in not dying out while you pour. Start the engine. Slowly introduce the Sea Foam into the line. There is no hurry here. Once you get about 1/3 can down the hose, turn off the motor and let it sit for around 10 min. The start it up, and watch the show. After a couple of minutes, go drive it "spiritedly" like you have heard to do. It might continue to smoke, don't worry, let it do what it has to.
The second photo represent SLOWLY pouring the liquid in to the hose. DO NOT SUBMERSE THE HOSE IN TO THE CAN. You will destroy your motor if it tries to compress a large helping of non compressible fluid. It is easier if you have someone in the truck on the throttle aiding it in not dying out while you pour. Start the engine. Slowly introduce the Sea Foam into the line. There is no hurry here. Once you get about 1/3 can down the hose, turn off the motor and let it sit for around 10 min. The start it up, and watch the show. After a couple of minutes, go drive it "spiritedly" like you have heard to do. It might continue to smoke, don't worry, let it do what it has to.
bzbatl
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Beautiful, thanks. I programmed it last night with the Hypertech, will see what that does today, then Sea Foam is going in tomorrow morning.
Thanks!
Thanks!
Chuckles
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Added Hyper tech III it did nothing for fuel milage. If there's a change in performance it's so slight I can't tell.
The latest is the e-fans still waiting for first fill up to tell.
The latest is the e-fans still waiting for first fill up to tell.
bzbatl
Full Access Member
Well that's disappointing. I figured a $200 investment would do *something*.
I drove on the freeway with no traffic at 2pm and it seemed like it got to speed easier. But that's complete Butt Dyno.
I decided to just fill up and see what my mileage is like on a full tank with just the Hypertech. Prior to that, I was getting ~380mi to a tank. I've never crossed over 400, so if it hits over that, I'm sold on it. After this first tank, I'll do the Sea Foam.
On another note, I put the HIDs in my wife's Mercedes and was pissed when I found out she's got efans already in hers. So jealous.
I drove on the freeway with no traffic at 2pm and it seemed like it got to speed easier. But that's complete Butt Dyno.
I decided to just fill up and see what my mileage is like on a full tank with just the Hypertech. Prior to that, I was getting ~380mi to a tank. I've never crossed over 400, so if it hits over that, I'm sold on it. After this first tank, I'll do the Sea Foam.
On another note, I put the HIDs in my wife's Mercedes and was pissed when I found out she's got efans already in hers. So jealous.
Chuckles
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It does do something that is noticeable by me. It shifts a little harder.
Looking to upgrade the stock muffler on my hoe. Basically looking to open up the exhaust a bit to compliment the TrueFlow SAI I have installed. Basically looking to just open the exhaust to improve air flow and hopefully mpg. I am not looking to break the bank on the muffler and am not looking to wake up the neighborhood. Magnaflow or Flowmaster are the mufflers I've been looking at. Any suggestions between the two.
Right now I avg around 13.5 mpg with the SAI and a performance tune. Although I think part of my problems with mpg increases is that most of my travel is "around town" local driving back and forth to work (7 mi commute with 8 or 9 traffic lights). So I guess most of my fuel goes into getting the darn thing moving, while I'm asking does anyone have any ideas on how to help improve the efficiency during this type of driving...outside of the "get everything out of the car" and maintenance topics which I have pretty much gotten down.
Right now I avg around 13.5 mpg with the SAI and a performance tune. Although I think part of my problems with mpg increases is that most of my travel is "around town" local driving back and forth to work (7 mi commute with 8 or 9 traffic lights). So I guess most of my fuel goes into getting the darn thing moving, while I'm asking does anyone have any ideas on how to help improve the efficiency during this type of driving...outside of the "get everything out of the car" and maintenance topics which I have pretty much gotten down.
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ruf455
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Magnaflow = smooth, mellow and strong
Flowmaster = throaty, muscle car like, a bit of drone.
Flowmaster = throaty, muscle car like, a bit of drone.
Chuckles
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First tank with efans no change in gas mileage. Still 12mpg. WTF!!!
Next is Taller skinnyer tires as 4:10's really weren't built for saving fuel.
Next is Taller skinnyer tires as 4:10's really weren't built for saving fuel.
06tahoez
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I have a custom tune on my Tahoe from Justin at Black Bear Performance. Since getting his tune I've seen an increase of 2 MPG. Throttle response is amazing now... I have a Flowmaster 50 SUV installed and an AEM Brute Force CAI waiting to be installed.
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