C5 airbox/air cleaner question. I'm puzzled.
08-14-2009, 12:57 PM
#1
Pro
Thread Starter
C5 airbox/air cleaner question. I'm puzzled.
Guys, I haven't had my C5 that long, but before the other day I had never looked carefully to see how air got into that shroud or cover in front of the air filter element. All I could find for an intake was a tiny little opening in that sloping front about the size and shape of a large postage stamp. Am I missing something, or is that all that feeds the engine? I know that the C5 designers were far cleverer than I, but if that small opening is all there is, then it seems woefully insufficient. I see that the 02-04 Z06 uses a cover with a somewhat larger opening and I am wondering if that might be a useful modification that would still keep my car looking stock underhood. What think you? The air filter element itself looks plenty big; but any benefits to one of the (factory-shape) overpriced K&N filters? I don't want to go to a cone setup or other aftermarket air feed. Thanks for any input, Ralph Boineau in central South Carolina
08-14-2009, 01:11 PM
#2
Drifting
Some folks do the "Swiss-Cheese Airbox Mod", wherein they drill the airbox cover full of holes to alleviate the factory's air restriction. If you would like, I can send you my "swiss cheesed" airbox cover (free-I took it off when I went with a cold air kit) and you can see if it makes a difference..
08-14-2009, 01:27 PM
#3
Drifting
Also, you could buy a Z06 airbox cover if you want the stock stealthy look...
The K&N filter question could stir up contention. They are less restrictive. But some say they don't filter as well as paper (likely true). That being said, I have a K&N panel filter in my FRC...
The K&N filter question could stir up contention. They are less restrictive. But some say they don't filter as well as paper (likely true). That being said, I have a K&N panel filter in my FRC...
08-14-2009, 01:50 PM
#4
Race Director
Look at this classified ad for Z06 leads...
http://forums.corvetteforum.com/c5-p...ner-cover.html
You can easily modify your oem top or a Z06 top into something which looks good and will allow more air intake.
This is from my Z16, which I opened up 2.5 times larger than original. I use a K&N (or S&B FILTER) in mine. Both are cotton gauze and I've never had any MAF contamination because I don't go crazy when it needs cleaning/oiling. I do that with every other oil/filter change.
I get no codes like I used to with an SLP "Blackwing". It sounds just as good...which is what most people equate with more power anyway.
Yes, I know. This is a very rare 110v version...
http://forums.corvetteforum.com/c5-p...ner-cover.html
You can easily modify your oem top or a Z06 top into something which looks good and will allow more air intake.
This is from my Z16, which I opened up 2.5 times larger than original. I use a K&N (or S&B FILTER) in mine. Both are cotton gauze and I've never had any MAF contamination because I don't go crazy when it needs cleaning/oiling. I do that with every other oil/filter change.
I get no codes like I used to with an SLP "Blackwing". It sounds just as good...which is what most people equate with more power anyway.
Yes, I know. This is a very rare 110v version...
Last edited by hotwheels57; 08-14-2009 at 01:55 PM.
08-14-2009, 04:48 PM
#5
Pro
Thread Starter
Thanks for responses, still puzzled
I guess someone like me who grew up in the 60's and had a bunch of high performance cars with big open-element air cleaners just can't imagine how a dippy little opening in that airbox cover can possibly feed all the air that engine needs. But obviously it works, as my car will flirt with 13 flat in the quarter-mile as it sits. I'll have to get a Z06 cover or do something else regardless whether it helps or not, as that little hole bugs me now. Thanks for your time. Ralph Boineau in central South Carolina
08-14-2009, 07:15 PM
#7
Le Mans Master
Your 2003 C5 breathes through the slit in the front PLUS both sides of the air cleaner.
This is an improvement over early C5s (1997-2000), which only breathed through two postage stamp sized "tubes".
I put an 2002 ZO6 air cleaner cover on my 1998 C5 and recommend this to all early C5 owners.
Your 2003 should provide more air than you need. The design is to minimize the chance of water getting into your air intake, including if you raise your hood after washing or driving in the rain.
This is an improvement over early C5s (1997-2000), which only breathed through two postage stamp sized "tubes".
I put an 2002 ZO6 air cleaner cover on my 1998 C5 and recommend this to all early C5 owners.
Your 2003 should provide more air than you need. The design is to minimize the chance of water getting into your air intake, including if you raise your hood after washing or driving in the rain.
08-14-2009, 07:21 PM
#9
Le Mans Master
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St. Jude Donor '11-'12-'13-'14-'15
I played around with my stock setup and got a pretty big path to the filter and it looked bone stock (for you people dealing with the CA smog *****);
I cut the runners out leaving only the two outer walls and then glued on a new cover;
Then cut corresponding holes in the shroud to allow cold air in;
I cut the runners out leaving only the two outer walls and then glued on a new cover;
Then cut corresponding holes in the shroud to allow cold air in;
08-16-2009, 04:26 AM
#12
Le Mans Master
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St. Jude Donor '11-'12-'13-'14-'15
It was merely an experiment, I was just playing around to see if I could get cold air in a larger volume while keeping it toally stock looking...
Tim
08-16-2009, 04:05 PM
#15
I'm new to the Corvette world and LS1's but based on what I have learned while experimenting and owning other fast cars, I'm pretty sure that the stock airbox is sucking more than enough air for a stock LS1 engine. 350 horsepower from a fuel efficient, naturally aspirated, single cam 350 ci engine is not too shabby. I'm pretty sure that the GM engineers designed the airbox like that for a reason.
I have experimented with open-type air intakes and K&N filters in the past (other cars) and it's been my experience that there never were any significant horsepower gains. The only result was hotter and dirtier air getting sucked into the engine with a greater risk of water ingestion. Just my two cents.
I have experimented with open-type air intakes and K&N filters in the past (other cars) and it's been my experience that there never were any significant horsepower gains. The only result was hotter and dirtier air getting sucked into the engine with a greater risk of water ingestion. Just my two cents.
Last edited by Cybermind; 08-16-2009 at 04:12 PM.
08-17-2009, 12:49 AM
#16
Melting Slicks
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St. Jude Donor '13
Ahh grasshopper. The very first mod many do is let that LS1 breathe. My advice is don't worry, be happy. There is a nasty disease called the "mod bug". It starts right where you're at now, asking questions. Thousands of dollars later, and many wasted hours, you're still not there. There is no cure. No support groups. Nothing. You'll think the folks here are very helpful, but the truth is they're just enablers.
I tried.
I tried.
08-17-2009, 05:54 AM
#17
Tech Contributor
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St. Jude Donor '09-'10-'11
Ahh grasshopper. The very first mod many do is let that LS1 breathe. My advice is don't worry, be happy. There is a nasty disease called the "mod bug". It starts right where you're at now, asking questions. Thousands of dollars later, and many wasted hours, you're still not there. There is no cure. No support groups. Nothing. You'll think the folks here are very helpful, but the truth is they're just enablers.
I tried.
I tried.
How true it really is!! 
08-17-2009, 07:14 AM
#18
Team Owner
Dont let the air filter housing fool you. Its very well designed and breathes just fine. In addition to the small opening in the front the entire perimeter is open and allows air to enter the box. There is no need for huge open elements, even on the older cars.
A nice air intake system is a very popular mod but dont expect much from it in the way of actual power. The sound will be a bit more aggressive, which is nice, but the OE filter is well engineered and not much of a a bottle neck.
Once you start with other mods such as headers, a cam, etc etc, the air filter will be a benefit.
I personally went with a 02' Z06 air box rather than waste money on all these ridiculously expensive wiz bang, gizmo air filters. Got it for $20 off the forum.
A nice air intake system is a very popular mod but dont expect much from it in the way of actual power. The sound will be a bit more aggressive, which is nice, but the OE filter is well engineered and not much of a a bottle neck.
Once you start with other mods such as headers, a cam, etc etc, the air filter will be a benefit.
I personally went with a 02' Z06 air box rather than waste money on all these ridiculously expensive wiz bang, gizmo air filters. Got it for $20 off the forum.
Last edited by Chevy Guy; 08-17-2009 at 12:05 PM.
