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View Full Version : DFCO and Exhaust popping



Chalky
November 6th, 2006, 08:31 PM
Can DFCO be used to reduce/eliminate popping sounds from LT headers and a Borla exhaust?

Can has had VE and MAF tuning with AFR dialed in around 12.9:1.

Tordne
November 6th, 2006, 09:09 PM
I find that DFCO cause popping on enable and disable :frown:

Chalky
November 7th, 2006, 09:11 AM
What would a solution be?

dfe1
November 7th, 2006, 11:20 AM
What would a solution be?
Ear plugs.

I have some pretty aggressive DFCO settings in my 01 C5, and in my 02 Silverado and it seems to have eliminated the popping I had previously. I've heard Andrew's comment before about popping on enable and/or disable, but that isn't an issue with the vehicles I've messed with. For reference, the C5 has LT headers and 3" high flow cats along with 3" cat-back.

ringram
November 7th, 2006, 12:07 PM
I think its due to the dfco & or timing ramp in and out. Basically spark will ramp to a very low value meaning charge is ignited just as its heading out the cyinder into the exhaust, rather than at an optimal point.
You can ramp it faster and see what that does I think it helped on mine.

Bruce Melton
November 7th, 2006, 04:00 PM
Any minor exhaust leak will contibute to the popping. Headers, Borlas, resonance and popping are a tough combination.

I have had some exhaust systems that caused serious concern in the neighborhood, but those were too much for me too.
Loud is fun--briefly :Eyecrazy:

Xtnct00WS6
November 12th, 2006, 04:40 PM
Verify that you're not too lean down low. I was pretty lean in the 15 MAP column so I added a tiney bit of fuel and it's much better now. FWIW I have an open borla and LT's too. It would only pop when I let off the gas after going over around 3k rpm.

Chalky
November 12th, 2006, 04:50 PM
Verify that you're not too lean down low. I was pretty lean in the 15 MAP column so I added a tiney bit of fuel and it's much better now. FWIW I have an open borla and LT's too. It would only pop when I let off the gas after going over around 3k rpm.
Sorry but what table are you referring to? Main VE?

Xtnct00WS6
November 12th, 2006, 05:24 PM
B0101 which is the main ve table.

Chalky
November 12th, 2006, 05:29 PM
B0101 which is the main ve table.

Gotcha.

I'll give it a try. When I did my VE tune, I kind of blew off tuning the lower columns as I was not seeing any consistent activity below MAP 30/35!