k&n & Imco change....
Thread Starter
Member
Joined: 03-31-2007
Posts: 43
From: new hartford ct.
Thank's laborkel!!!!! Quess I am smart enogh to know I am stupid when it's 07 engine's!!! Consolidating the imput, it seems okay to make a statement....Pulling the ecm has immediate effect for little money. And accurate. Waiting for a couple hundred miles and running somewhat lean, it will "still" return to the right mix of air and fuel. Thank's Kelldog
Senior Member
Joined: 07-17-2006
Posts: 6,053
From: Dallas, GA
Some light reading for ya.
I think you worry too much. Install and drive. Do you realize how many changes the PCM makes as you are driving? If you get a light, find out why, and clear it the right way. Today that is so easy and FREE at most auto parts stores. Pulling the fuse is the same, but it only removes power to your PCM. And resets to the factory default settings. It will clear a code, but the same issues will still be there until the PCM adjust itself.
Relax.
If you disconnect your battery to reset your check engine light. You may erase valuable memory from the computer and wind up disabling your car stereo and factory installed alarm.
Why is your check engine light on? The check engine light or service engine soon light is directly connected to your car’s computer and monitors the emission system. This warning light was federally mandated by our government to notify the driver that the vehicle may be polluting the atmosphere.
The check engine light is all about the war on pollution, global warming and smog. One of the main problems with this emission system-monitoring device is that it is very sensitive. Often you will find that this light is illuminated for a minor malfunction or even an intermittent problem.
This is why the first step in the solution to the problem is to clear the code and retest the vehicle to see if the light returns. The problem with this is that the fastest way to reset the check engine light is to disconnect the battery. But there are many systems in your vehicle that require constant battery power.
Most people don’t realize that your vehicle computer adapts to your driving habits. Your vehicle computer stores memory functions such as shift points, idle speed and throttle position for the primary driver. When you disconnect the vehicle battery you wipe out this memory and the computer returns to a default mode, which may make the vehicle run in a manner that you are not accustomed to.
Why is your check engine light on? The check engine light or service engine soon light is directly connected to your car’s computer and monitors the emission system. This warning light was federally mandated by our government to notify the driver that the vehicle may be polluting the atmosphere.
The check engine light is all about the war on pollution, global warming and smog. One of the main problems with this emission system-monitoring device is that it is very sensitive. Often you will find that this light is illuminated for a minor malfunction or even an intermittent problem.
This is why the first step in the solution to the problem is to clear the code and retest the vehicle to see if the light returns. The problem with this is that the fastest way to reset the check engine light is to disconnect the battery. But there are many systems in your vehicle that require constant battery power.
Most people don’t realize that your vehicle computer adapts to your driving habits. Your vehicle computer stores memory functions such as shift points, idle speed and throttle position for the primary driver. When you disconnect the vehicle battery you wipe out this memory and the computer returns to a default mode, which may make the vehicle run in a manner that you are not accustomed to.
Relax.
Thread Starter
Member
Joined: 03-31-2007
Posts: 43
From: new hartford ct.
Geeez guy's. I am relaxed!!!!! You can live with many different opinion's on hubcap's, pinstriping,etc.! But this is a big deal. We are talking about altering a well made engine that has been refined over the year's. Like good discussion on a important subject "THAT DOES HAVE ALOT OF DIFFRENT ANSWERS IN PAST FORUMS." Really would like to get this right for other hhr owners too.Can any of you guy's call the k&n techs.,and airaid,cgn,etc.You will see what I mean.Got a k& n on order and the tech. stated it changes in seconds. YIKES!!!!!!! That's not what anybody else said!!!!!! KELLDOG
Member
Joined: 09-03-2007
Posts: 40
From: BC
Internal combustion engines have not changed much in the way of basic principles.
Suck air in add fuel, compress ignite, BANG push piston down, pump out exhaust, repeat cycle.
Fuel mapping and ignition have made significant changes/improvements.
The stock set up sucks air from a box that is fed cold outside air.
Adequate for most daily drivers, but designed to be quiet as well.
Increasing air in and exhaust out helps substantially in the process thereby increasing HP and torque.
Any modern engine nowdays is adaptable to certain amounts of flow changes. That's how they work right?
Yes you can max out the stock injectors and fuel mapping.
I doubt this would happen with a CAI and exhaust.
Suck air in add fuel, compress ignite, BANG push piston down, pump out exhaust, repeat cycle.
Fuel mapping and ignition have made significant changes/improvements.
The stock set up sucks air from a box that is fed cold outside air.
Adequate for most daily drivers, but designed to be quiet as well.
Increasing air in and exhaust out helps substantially in the process thereby increasing HP and torque.
Any modern engine nowdays is adaptable to certain amounts of flow changes. That's how they work right?
Yes you can max out the stock injectors and fuel mapping.
I doubt this would happen with a CAI and exhaust.
Thread Starter
Member
Joined: 03-31-2007
Posts: 43
From: new hartford ct.
Thank's for all the help!!!!!!!!! Got alot of flack from muff. shop's of price and "will it fit". Sooooooo took out the hack saw and took the turtle muff. off! Started her up for the heck of it after sawing off the muff. Was taking back that it was not all that loud! Decided on waiting to put the imco on, and get a resonator tip off a straight pipe and tried that. VOILLA!!!!! Perfect sound. Took her around the block and was louder but not that much. This is a large resonator! Over a foot and made for suv's which is also bumped up to 2" dia. from the cutoff by a coupling. Going with the by far the popular opinon to de-resrict for h.p and gas.Think I did that big time. NOW I do have the yellow light on on the right hand side of the dash.A circle with tc in it. Now what? Wait to ajust? Thank's again and hope everybody had a great weekend in this great country!!!!!!! KELLDOG
Senior Member
Joined: 07-26-2007
Posts: 1,789
From: Pekin, Illinois
I could be wrong here, I haven't noticed this light onmine yet, but I think that is the traction control light if equipped. Someone correct me if I am wrong here.
As far as the muffler concern you might want a muffler on there for at least some back presure. To free flowing and you might not like the outcome. I know sound is great and everyone loves to hear the rumble, why else do it, but check to make sure you wln't hurt anything without a little back pressure.
As far as the muffler concern you might want a muffler on there for at least some back presure. To free flowing and you might not like the outcome. I know sound is great and everyone loves to hear the rumble, why else do it, but check to make sure you wln't hurt anything without a little back pressure.
Thread Starter
Member
Joined: 03-31-2007
Posts: 43
From: new hartford ct.
Geez stick! Here we go again!!!!!!! BACKPRESSURE:::::: NOt going for loud but if it comes, it comes. Why not get a few more mpg and hp for 46 bucks. On my knees guy's .....begging!!!!!!! DO we need back pressure?????? A little ,, alot.. or none....! There has to be ONE answer on this.The only engines I know about and race, and compete are r.c airplanes. The only good backpressure does for them is to pressurize the tank for delivery of nitro. I am alway's deresricting muff.s for highest r.p.m. keeping just under regulation's. Thank's stick for the reply but what outcome might I not like with a "to free flowing muff."And why would a traction control light come on "right away" after cutting off the muff?? KELLDOG
Senior Member
Joined: 07-26-2007
Posts: 1,789
From: Pekin, Illinois
I got this off a Popular Mechanics website http://www.popularmechanis.com/how_t...ral/automotive
Hope it helps...
Some back pressure is beneficial at low speed, because slowing down the flow pattern of intake and exhaust gases improves performance somewhat. Many engines have 2-stage mufflers with an internal spring-loaded valve. These mufflers maintain a specified amount of back pressure for good low-speed performance. But when the engine is at higher speed and there's more exhaust gas to flow through the muffler, back pressure builds up. Before it can become excessive, it pushes open the spring-loaded valve, and the gases take a far less restrictive flow through the muffler. This "second stage" permits the engine to develop considerably greater horsepower at higher rpm.
This is the school of thought I always stuck with and never had any problem with any exhaust I ever changed.
As far as the tc light I have no idea.....sorry
Hope it helps...
Some back pressure is beneficial at low speed, because slowing down the flow pattern of intake and exhaust gases improves performance somewhat. Many engines have 2-stage mufflers with an internal spring-loaded valve. These mufflers maintain a specified amount of back pressure for good low-speed performance. But when the engine is at higher speed and there's more exhaust gas to flow through the muffler, back pressure builds up. Before it can become excessive, it pushes open the spring-loaded valve, and the gases take a far less restrictive flow through the muffler. This "second stage" permits the engine to develop considerably greater horsepower at higher rpm.
This is the school of thought I always stuck with and never had any problem with any exhaust I ever changed.
As far as the tc light I have no idea.....sorry
Member
Joined: 09-03-2007
Posts: 40
From: BC
I don't think it's backpressure you want but you want the right size pipe for flow.
Many people make the mistake of going too large a diameter pipe and this slows the exhaust gas down at lower rpm's. Losing torque.
Too small a pipe and you have.......backpressure. Not required.
This affects the efficiency/performance of the motor.
If there is too much backpressure the motor does not completely fill the cyl with air during scavenging.
The muffler can be straight through but auto manufacturers are dealing with noise restrictions and drive by tests.
I think the stock design is adequate but always a compromise because of these other perameters.
A 2 1/4" straight through Magnaflow or equivelant is not really that loud and is a good muffler IMO.
Many people make the mistake of going too large a diameter pipe and this slows the exhaust gas down at lower rpm's. Losing torque.
Too small a pipe and you have.......backpressure. Not required.
This affects the efficiency/performance of the motor.
If there is too much backpressure the motor does not completely fill the cyl with air during scavenging.
The muffler can be straight through but auto manufacturers are dealing with noise restrictions and drive by tests.
I think the stock design is adequate but always a compromise because of these other perameters.
A 2 1/4" straight through Magnaflow or equivelant is not really that loud and is a good muffler IMO.
