[Brey335i]

Requisite Cobb thread of the day

I've noticed since switching from Procede to Cobb for daily driving that Cobb has made my exhaust a lot louder. It's louder, gurgles more, and pops between shifts and on deceleration.

I've also noticed a hint of smoke that isn't there with the Procede.

Has anyone else noticed this stuff with a completely catless exhaust? My theory is that it's running very rich. It's got to be tune related as it disappears with the Procede.

[themyst]

Why don't you log the Afr and take a look yourself? The afr is true, being that there is no bias calculation going on like the piggys.

[BMWsky]

Running on Stage 1, my AFR is usually right around 14~15 while cruising around town. At WOT and under load, it usually runs in the 12's. I do notice that after a track day, my pipes are BLACK!!! (Stock exhaust...for now.)

[135i]

So that explains the flames always coming out of my exhaust

[mithiral67]

Louder yes, no smoke, and logs show solid afrs.

[tofu-]

Originally Posted by 135i

So that explains the flames always coming out of my exhaust

there's a thread on the jb forums about wanting flames out of the ehxuast

[Brey335i]

Originally Posted by mithiral67

Louder yes, no smoke, and logs show solid afrs.

Completely catless?

[mithiral67]

No, still have secondaries.

[Brey335i]

Originally Posted by mithiral67

No, still have secondaries.

That might be why.

Did some logging. My AFRs all fall in line with what I have seen from everyone else running Cobb. I'm just gonna get some high flows welded in and see if that helps. Need to get rid of the smell anyways.

[mithiral67]

I can smell my exhaust at start up while the secondaries are cold, but no visible smoke.

[Jeff@TopGearSolutions]

I dont miss the no cat smell anymore. I get enough fumes from my bike haha

[Alan l.]

I noticed my exhaust tips are also more black with the Cobb tune. Doesn't bother me knowing my AFR's are so conservative.

[Bleep]

Better to be rich than lean.

[ruphianh]

Originally Posted by Brey335i

Requisite Cobb thread of the day

I've noticed since switching from Procede to Cobb for daily driving that Cobb has made my exhaust a lot louder. It's louder, gurgles more, and pops between shifts and on deceleration.

I've also noticed a hint of smoke that isn't there with the Procede.

Has anyone else noticed this stuff with a completely catless exhaust? My theory is that it's running very rich. It's got to be tune related as it disappears with the Procede.

Why did you switch???

[uwotm8]

I haven't logged my car with the AP, but the COBB tunes on subarus (my former world) were always very rich and not regarded as aggressive at all. The simple fact is they need to release a safe product that works at sea level, 1 mile above sea level, 90 degree temps, and 30 degree temps etc, so they need to ensure that the car will run safely enough in different conditions. That's why it generally does run leaner. As far as your motor's safety is concerned, that's not a bad thing .

[Brey335i]

Originally Posted by ruphianh

Why did you switch???

I'm addicted to change

[OpenFlash]

Originally Posted by djsniggedy

I haven't logged my car with the AP, but the COBB tunes on subarus (my former world) were always very rich and not regarded as aggressive at all. The simple fact is they need to release a safe product that works at sea level, 1 mile above sea level, 90 degree temps, and 30 degree temps etc, so they need to ensure that the car will run safely enough in different conditions. That's why it generally does run leaner. As far as your motor's safety is concerned, that's not a bad thing .

The MSD80/81 run closed loop during all load conditions. So the desired AFR will be reached regardless of conditions. Also running this direct injection engine at say 11:1 doesn't make it operationally safer than running it at 12:1. The stratified air/fuel charge eliminates the need for over-fueling (ie, running rich) in order to get a stable and complete burn. I've always felt the excessively rich AFRs were more marketing driven than anything else. People who aren't familiar with tuning direct injection engines (99% of all users) will naturally feel more comfortable with a tune that runs richer than leaner. Whether or not this is true.

Shiv

[ruphianh]

Originally Posted by Brey335i

I'm addicted to change

I just hooked up with the procede V5 w/ meth.

Now I'm addicted to Meth. . . the vroom vroom meth. Its not to late to make the switch back!

The only smoke I see is all 4 tires spinning

[E90SoFlo]

Originally Posted by ruphianh

I just hooked up with the procede V5 w/ meth.

Now I'm addicted to Meth. . . the vroom vroom meth. Its not to late to make the switch back!

The only smoke I see is all 4 tires spinning

Cool story bro

[Brey335i]

Originally Posted by ruphianh

I just hooked up with the procede V5 w/ meth.

Now I'm addicted to Meth. . . the vroom vroom meth. Its not to late to make the switch back!

The only smoke I see is all 4 tires spinning

I ran Procede and Meth. In fact I haven't sold it either...

[Rob@Cobb]

Originally Posted by shiv@vishnu

The MSD80/81 run closed loop during all load conditions. So the desired AFR will be reached regardless of conditions. Also running this direct injection engine at say 11:1 doesn't make it operationally safer than running it at 12:1. The stratified air/fuel charge eliminates the need for over-fueling (ie, running rich) in order to get a stable and complete burn. I've always felt the excessively rich AFRs were more marketing driven than anything else. People who aren't familiar with tuning direct injection engines (99% of all users) will naturally feel more comfortable with a tune that runs richer than leaner. Whether or not this is true.

Shiv

I'm not sure stratified fuel mode has much to do with high load fuel targets. Stratified fuel mode is only attained when light load cruising for a long period of time using a good quality fuel. It's a economy mode of sorts which does not come into play with high or medium load strategies. During strat mode the throttle plate is flipped completely open using the fuel to control motor speed and torque output. Bosch has some pretty good reading material on the subject if you are interested. I could certainly point you in the right direction.

I don't think we have marketed the fuel targets of our tune. In fact I believe it was the customers who were excited to see a solution which could properly control fuel. We simply produce good tunes which make good safe power. Those tunes may include a nice fuel curve at any load, properly timed motor based on ECU/det can/dyno feedback, and a boost level within the limits of the turbos.

Cheers,
Rob

[OpenFlash]

Originally Posted by Rob@Cobb

I'm not sure stratisfied fuel mode has much to do with high load fuel targets. Stratisifed fuel mode is only attained when light load cruising for a long period of time using a good quality fuel. It's a economy mode of sorts which does not come into play with high or medium load strategies. During strat mode the throttle plate is flipped completely open using the fuel to control motor speed and torque output. Bosch has some pretty good reading material on the subject if you are interested. I could certainly point you in the right direction.

I don't think we have marketed the fuel targets of our tune. In fact I believe it was the customers who were excited to see a solution which could properly control fuel. We simply produce good tunes which make good safe power. Those tunes may include a nice fuel curve at any load, properly timed motor based on ECU/det can/dyno feedback, and a boost level within the limits of the turbos.

Cheers,
Rob

Before we begin, I'm not familiar with the term "stratisified". Are you sure you don't mean stratified?