When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
So I ordered a 15776148 from an amazon.com vendor. It arrived quickly but the morons didn't put it in a shipping box; instead they slapped a usps 2-day label on it and shipped it. By the time I got it, the box is all taped up (usps handy-work?) and there's a 1/2" hole in the side that corresponds to damage to the filter itself. Anyway: amazon, so I know I'm getting my money back.
The AC/Delco box has both the GM (15776148) and AC/Delco part numbers (A3077C) on it. But the filter is blue instead of white. I know Delco has this game they play where they have "OEM" and also "Professional". And I know the "Professional" is usually junk.
Is the blue filter the "good" one? I'm not interested in K&N or anything like that, I just want the high-quality OEM filter.
I haven't been back to this thread in a while, but on this LS7 air filter issue, it's looking like ACDelco as fu**ed 12/13 Z06 owners and all ZR1 owners.
I did quite a bit of research on the LS7 and LS9 filter issue earlier this year.
During my last chassis dyno test of the engine in my Z06 with an MSD Atomic Air Force intake manifold, the OE air filter assembly and an OE air filter, I noted that the power peak moved down 200 rpm. I thought that strange. After some thought and research, I decided a possible reason for the change might be a restrictive air filter, but first...the back story.
Back in 2009, when GM introduced the 638-hp, supercharged, LS9 in the C6 ZR1, it gave that engine a new, less-restrictive air filter to support the obvious significant increase in airflow from enough to support 505-hp to support 638-hp.
In 2006, when the LS7 was introduced, it used a new air filter design produced by the Donaldson Company, a filter media Donaldson called "PowerCore". During the LS9 development, GM wanted an air filter the same size as the LS7 filter to fit in an air filter assembly which would carry over from LS7. GM went back to Donaldson for help and it developed a new filter, the same size as the LS7 filter, but using a new, less-restrictive filter media called "PowerCore G2". The new filters were installed on all LS9s and, up until 2012, were only used on that engine.
For the 2012 model year, in response to more stringent exhaust emissions standards in California, GM built Corvette exhaust systems with four catylitic converters. While the 4-cat exhaust was, apparently, not a big deal on the supercharged LS9, on the normally aspirated LS7, it restricted the exhaust enough that the engine's power fell below the 505-hp mark which made the engine famous. During the development of the '12 LS7, GM determined it could reduce intake restriction enough to offset the increase in exhaust restruction such that the power level remained at 505-hp if it used the LS9 filter made with the Donaldson PowerCore G2 media. As such, all 2012 and 2013 Z06es and 427 Convertibles used the LS9 air filter.
Fast forward to 18 months ago:
I ordered a new air filter for my 12 Z06 from Amazon.com. When it arrived, I noted the filter media was slightly different but didn't think anything about it at the time.
Then, back in February, I tested the MSD Atomic Air Force intake manifold I installed on the engine and noted that, while peak power and torque improved significantly, that the power peak moved down slightly. I thought that strange and then remembered how the air filter looked different.
I did some research on the Donaldson Company web site and learned that Donaldson has two similar-appearing, but different-performing filter media: "PowerCore" and "PowerCore G2". The web site implied that the PowerCore G2 was capable of higher flow rates but no specific information as to the two media's actual flow rates was given. Imagery on the site indicated that the PowerCore G2 media was the media used in my original 2012 LS7 air filter and the older, PowerCore media was used in replacement, AC Delco A3107Cs filter I had ordered from Amazon and, later, Zip Products. I contacted Donaldson's Marketing Manger, Rod Radosevich. Initially, Mr. Radosevich suggested I email him some questions. I did so, asking about differences between PowerCore and PowerCore G2. He emailed back saying that Donaldson Company would not answer my questions.
Here is an image showing the difference between the two.
Some more research on the Internet found a statement, the original source unknown, that the PowerCore G2 LS9 and '12/'13 LS7 air filter are capable of flowing 850-cfm, a 19% increase in flow over the earlier LS7 filter which was made with PowerCore media.
Then, I took my research in a different direction, trying to better understand AC Delco's current offering for air filters. Turns out that the 2006-2011 Z06 air filter is an A3077C and has always used the PowerCore media. The factory-installed 09-13 LS9/12-13 LS7 filters (GM PN 25940997) used the PowerCore G2 media, however, the AC Delco replacement filters (PN A3107C) I have seen so far, one from Amazon.com and one from Zip Products, both of which were purchased in the last 12 months, also use the more-restrictive PowerCore media.
I suspect that ACD, confronted with the cost of the PowerCore G2 media decided it was not important to sell the proper filter for LS9s and 12-13 LS7s and is ordering it's current, replacement LS3, LS7 and LS9 filters from Donaldson to be made with PowerCore rather than the better. PowerCore G2 media.
If that's true, then anyone putting an OE-replacement A3107C filter on an LS9 or 12-13 LS7 is gong to experience a loss in performance.
How much of a loss?
My chassis dyno testing indicates 4-hp. That's based a three test average of each filter. The dyno data was SAE corrected. While that seems insignificant, remember, I'm testing a near stock engine. The more horsepower the engine makes, the more air it needs and the more restrictive the filter becomes.
On an LS9, because of that engine's higher air flow, I suspect the loss would be larger but I have no data to support that belief because I didn't have a ZR-1 to use in testing.
While a 4-hp loss is not really a big deal, it's the principle of the thing which pisses me off. GM should provide replacement parts which do not decrease the performance of its products.
This is my first corvette. I just ordered online and was sent the AC Delco A3077C filter when I ordered the OEM GM 15776148 filter. So, did I just get screwed by the supplier passing off AC Delco as the OEM part? MY understanding is there are genuine GM parts then also AC Delco parts which are close, but perhaps not 100% OEM quality. The supplier is telling me that GM doesn't make an air filter only AC Delco that gets put in Corvettes at the factory. I have a 2010 GS btw.
Also, it seems there are different versions within AC Delco. The filter I received is blue in color. How can I be sure I got the AC Delco "OEM" filter which appears to be the best of the AC Delco brand?
These are all likely stupid questions but thanks for putting up with me...
12 and up Z06es used the Donaldson PowerCore G2 filter to reduce airflow restriction on the intake side of the engine after they went to four cats on the exhaust side. It was how they kept the 12s and 13s at 505-hp.
For unknown reasons the filter media Donaldson uses in both the PowerCore and PowerCore G2 filters is colored blue.
Last edited by Hib Halverson; 06-05-2016 at 01:04 PM.
Reason: more accurate information
12 and up Z06es used the Donaldson PowerCore filter to reduce airflow restriction on the intake side of the engine after they went to four cats on the exhaust side. It was how they kept the 12s and 13s at 505-hp. It so happens that for unknown reasons the filter media Donaldson uses is colored blue.
It's likely that the blue filters have superceeded the earlier style.
That makes me wonder what you believe the earlier style was, since I have both an OEM (factory install) blue filter with the A3077C AC Delco stamp on one side and Donaldson Powercore stamp on the other side for my '08 coupe and another for a '10 GS.
In '09 there were 3 different Donaldson Powercore filters. One for LS3's, one for Z06's, and one for ZR1's. Somewhere on this forum was a photo of all 3 together. They were physically and visually different, yet they were all blue.
The AC Delco filter I received does have a sticker that says Power Core & Donaldson. It's blue in color but it's not a GM filter, it's AC Delco. So, I suppose GM didn't actually make their own air filter?
In '09 there were 3 different Donaldson Powercore filters. One for LS3's, one for Z06's, and one for ZR1's. Somewhere on this forum was a photo of all 3 together. They were physically and visually different, yet they were all blue.
No, but two of those are in the other photo. The third one in the other photo is for the LS3 and the "pleats" or "cores" are even closer together than the Z06 filter.
The AC Delco filter I received does have a sticker that says Power Core & Donaldson. It's blue in color but it's not a GM filter, it's AC Delco. So, I suppose GM didn't actually make their own air filter?
Gm buys parts from many suppliers, and assembles them into completed vehicles. They do not "make" most of the parts used in this process. AC Delco is now a separate company, but was part of GM, and is still a main supplier.
Gm buys parts from many suppliers, and assembles them into completed vehicles. They do not "make" most of the parts used in this process. AC Delco is now a separate company, but was part of GM, and is still a main supplier.
Ah, ok I didn't realize they were part of GM before. So, in this case it may be ok. What about something like TPMS sensors then? Are AC Delco as good as GM even though the GM units cost more?
I haven't been back to this thread in a while, but on this LS7 air filter issue, it's looking like ACDelco as fu**ed 12/13 Z06 owners and all ZR1 owners.
I did quite a bit of research on the LS7 and LS9 filter issue earlier this year.
During my last chassis dyno test of the engine in my Z06 with an MSD Atomic Air Force intake manifold, the OE air filter assembly and an OE air filter, I noted that the power peak moved down 200 rpm. I thought that strange. After some thought and research, I decided a possible reason for the change might be a restrictive air filter, but first...the back story.
Back in 2009, when GM introduced the 638-hp, supercharged, LS9 in the C6 ZR1, it gave that engine a new, less-restrictive air filter to support the obvious significant increase in airflow from enough to support 505-hp to support 638-hp.
In 2006, when the LS7 was introduced, it used a new air filter design produced by the Donaldson Company, a filter media Donaldson called "PowerCore". During the LS9 development, GM wanted an air filter the same size as the LS7 filter to fit in an air filter assembly which would carry over from LS7. GM went back to Donaldson for help and it developed a new filter, the same size as the LS7 filter, but using a new, less-restrictive filter media called "PowerCore G2". The new filters were installed on all LS9s and, up until 2012, were only used on that engine.
For the 2012 model year, in response to more stringent exhaust emissions standards in California, GM built Corvette exhaust systems with four catylitic converters. While the 4-cat exhaust was, apparently, not a big deal on the supercharged LS9, on the normally aspirated LS7, it restricted the exhaust enough that the engine's power fell below the 505-hp mark which made the engine famous. During the development of the '12 LS7, GM determined it could reduce intake restriction enough to offset the increase in exhaust restruction such that the power level remained at 505-hp if it used the LS9 filter made with the Donaldson PowerCore G2 media. As such, all 2012 and 2013 Z06es and 427 Convertibles used the LS9 air filter.
Fast forward to 18 months ago:
I ordered a new air filter for my 12 Z06 from Amazon.com. When it arrived, I noted the filter media was slightly different but didn't think anything about it at the time.
Then, back in February, I tested the MSD Atomic Air Force intake manifold I installed on the engine and noted that, while peak power and torque improved significantly, that the power peak moved down slightly. I thought that strange and then remembered how the air filter looked different.
I did some research on the Donaldson Company web site and learned that Donaldson has two similar-appearing, but different-performing filter media: "PowerCore" and "PowerCore G2". The web site implied that the PowerCore G2 was capable of higher flow rates but no specific information as to the two media's actual flow rates was given. Imagery on the site indicated that the PowerCore G2 media was the media used in my original 2012 LS7 air filter and the older, PowerCore media was used in replacement, AC Delco A3107Cs filter I had ordered from Amazon and, later, Zip Products. I contacted Donaldson's Marketing Manger, Rod Radosevich. Initially, Mr. Radosevich suggested I email him some questions. I did so, asking about differences between PowerCore and PowerCore G2. He emailed back saying that Donaldson Company would not answer my questions.
Here is an image showing the difference between the two.
Some more research on the Internet found a statement, the original source unknown, that the PowerCore G2 LS9 and '12/'13 LS7 air filter are capable of flowing 850-cfm, a 19% increase in flow over the earlier LS7 filter which was made with PowerCore media.
Then, I took my research in a different direction, trying to better understand AC Delco's current offering for air filters. Turns out that the 2006-2011 Z06 air filter is an A3077C and has always used the PowerCore media. The factory-installed 09-13 LS9/12-13 LS7 filters (GM PN 25940997) used the PowerCore G2 media, however, the AC Delco replacement filters (PN A3107C) I have seen so far, one from Amazon.com and one from Zip Products, both of which were purchased in the last 12 months, also use the more-restrictive PowerCore media.
I suspect that ACD, confronted with the cost of the PowerCore G2 media decided it was not important to sell the proper filter for LS9s and 12-13 LS7s and is ordering it's current, replacement LS3, LS7 and LS9 filters from Donaldson to be made with PowerCore rather than the better. PowerCore G2 media.
If that's true, then anyone putting an OE-replacement A3107C filter on an LS9 or 12-13 LS7 is gong to experience a loss in performance.
How much of a loss?
My chassis dyno testing indicates 4-hp. That's based a three test average of each filter. The dyno data was SAE corrected. While that seems insignificant, remember, I'm testing a near stock engine. The more horsepower the engine makes, the more air it needs and the more restrictive the filter becomes.
On an LS9, because of that engine's higher air flow, I suspect the loss would be larger but I have no data to support that belief because I didn't have a ZR-1 to use in testing.
While a 4-hp loss is not really a big deal, it's the principle of the thing which pisses me off. GM should provide replacement parts which do not decrease the performance of its products.
Last edited by Hib Halverson; 04-16-2018 at 11:52 AM.
The air filter part number I see for a 2009 ZR1 gmpartsdirect.co is 25940997. acdelco shows A3107C. It's easy to find pictures of a box with both part numbers on it.
I guess I don't understand why you think the A3107C is a replacement for the A3077C? Is there a third set of part numbers that are no longer available?
I guess I don't understand why you think the A3107C is a replacement for the A3077C? Is there a third set of part numbers that are no longer available?
Please, remember, I'm talking about the filter media, not the entire filter.
Indeed A3077C is the filter for the early LS7 application and the A3107C is the filter for the late LS7 and LS9 applications. ACD is now using the same filter media for both, rather than PowerCore for one and PowerCore G2 for the other.
Last edited by Hib Halverson; 10-26-2017 at 11:47 PM.
Please, remember, I'm talking about the filter media, not the entire filter.
Indeed A3077C is the filter for the early LS7 application and the A3107C is the filter for the late LS7 and LS9 applications. ACD is not using the same filter media for both, rather than PowerCore for one and PowerCore G2 for the other.
Hib, did you mean is now using the same media (PowerCore) for both?
02-27-2015, 02:38 AM
What's the deal with LS7 air filters?
I just changed out the original filter in my 08Z and Amazon sent me a matching blue filter that looked the same as the original without the dirt.
This is also what parts-catalog.acdelco.com shows for my 2007 Z06. And for a 2009 or 2012 Z06.
