Yet another tireless thread on the Stock Airbox
12-08-2010, 08:12 PM
#1
Instructor
Thread Starter
Yet another tireless thread on the Stock Airbox
I feel almost guilty writing this. I've been doing a search on the ZR1 Registry and CF and it seems there's about a couple hundred threads on the issue.
I promise I will be brief. I can't find any pics of a 1992 Stock Airbox but I suspect mine has been cut. The reason is, the bottom of the lid is simply a huge cutout and the edges feel sharp - not factory. The air filter the car came with is a K&N.
I saw a post where someone said the stock airbox with the paper filter flowed better than the K&N and cutout? I've also seen posts where people "reverse" the airbox? Other people state they have an open airbox altogether so I am picturing box sides of the airbox being cut?
Anyway, I'd love some pics and perhaps a consensus on what is best for an otherwise stock ZR1 with exhaust. Also, any tips on reinforcing the stock air intake pipe? I think I read somewhere that some people use a wire coat hanger? Another person used Dryer ducting from home depot?
I promise I will be brief. I can't find any pics of a 1992 Stock Airbox but I suspect mine has been cut. The reason is, the bottom of the lid is simply a huge cutout and the edges feel sharp - not factory. The air filter the car came with is a K&N.
I saw a post where someone said the stock airbox with the paper filter flowed better than the K&N and cutout? I've also seen posts where people "reverse" the airbox? Other people state they have an open airbox altogether so I am picturing box sides of the airbox being cut?
Anyway, I'd love some pics and perhaps a consensus on what is best for an otherwise stock ZR1 with exhaust. Also, any tips on reinforcing the stock air intake pipe? I think I read somewhere that some people use a wire coat hanger? Another person used Dryer ducting from home depot?
12-08-2010, 08:52 PM
#2
Factory or open lid filter works good.
Open lid is stock but on the top it's open so you can see the top of the k and n filter.
I'd probably buy a new or good used duct. Yes, you can use all types of things to keep snorkel open, just make sure it doesn't get sucked into motor.
Open lid is stock but on the top it's open so you can see the top of the k and n filter.
I'd probably buy a new or good used duct. Yes, you can use all types of things to keep snorkel open, just make sure it doesn't get sucked into motor.
Last edited by xlr8nflorida; 12-10-2010 at 09:12 PM.
12-08-2010, 10:38 PM
#3
Racer
I feel almost guilty writing this. I've been doing a search on the ZR1 Registry and CF and it seems there's about a couple hundred threads on the issue.
I promise I will be brief. I can't find any pics of a 1992 Stock Airbox but I suspect mine has been cut. The reason is, the bottom of the lid is simply a huge cutout and the edges feel sharp - not factory. The air filter the car came with is a K&N.
I saw a post where someone said the stock airbox with the paper filter flowed better than the K&N and cutout? I've also seen posts where people "reverse" the airbox? Other people state they have an open airbox altogether so I am picturing box sides of the airbox being cut?
Anyway, I'd love some pics and perhaps a consensus on what is best for an otherwise stock ZR1 with exhaust. Also, any tips on reinforcing the stock air intake pipe? I think I read somewhere that some people use a wire coat hanger? Another person used Dryer ducting from home depot?
I promise I will be brief. I can't find any pics of a 1992 Stock Airbox but I suspect mine has been cut. The reason is, the bottom of the lid is simply a huge cutout and the edges feel sharp - not factory. The air filter the car came with is a K&N.
I saw a post where someone said the stock airbox with the paper filter flowed better than the K&N and cutout? I've also seen posts where people "reverse" the airbox? Other people state they have an open airbox altogether so I am picturing box sides of the airbox being cut?
Anyway, I'd love some pics and perhaps a consensus on what is best for an otherwise stock ZR1 with exhaust. Also, any tips on reinforcing the stock air intake pipe? I think I read somewhere that some people use a wire coat hanger? Another person used Dryer ducting from home depot?
12-09-2010, 02:50 PM
#4
Racer
I've used the same setup you have now, and it works well. I don't know how someone can say that an open lid and a K&N flows less that a stock setup...unlikely.
I have the "Forced Air" bumper breather setup. I don't know how much more it flows, but I cut another .10 off my e.t. in the 1/4 mi. after installing it.
I have the "Forced Air" bumper breather setup. I don't know how much more it flows, but I cut another .10 off my e.t. in the 1/4 mi. after installing it.
12-09-2010, 02:54 PM
#5
Instructor
Thread Starter
12-09-2010, 02:58 PM
#6
Instructor
Thread Starter
I've used the same setup you have now, and it works well. I don't know how someone can say that an open lid and a K&N flows less that a stock setup...unlikely.
I have the "Forced Air" bumper breather setup. I don't know how much more it flows, but I cut another .10 off my e.t. in the 1/4 mi. after installing it.
I have the "Forced Air" bumper breather setup. I don't know how much more it flows, but I cut another .10 off my e.t. in the 1/4 mi. after installing it.
http://forums.corvetteforum.com/c4-t...o-results.html
12-09-2010, 04:07 PM
#7
Drifting
The jist of my test was that none of the 3 set-up's tested showed a gain outside of what could be considered the normal run to run dyno variation - Except possibly the "Claw" with it's repeated slight improvements to mid-range power.
K&N filters can also be artificially restricted by over-oiling, although I don't think that was a factor here.
I see no reason not to use a cut-lid if it doesn't cost you anything, just don't expect much if any benefit from it.
K&N filters can also be artificially restricted by over-oiling, although I don't think that was a factor here.
I see no reason not to use a cut-lid if it doesn't cost you anything, just don't expect much if any benefit from it.
12-09-2010, 08:59 PM
#8
Le Mans Master
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Stock airbox has a bunch of vents cut in it. If a previous owner has cut the stock airbox, you might as well keep it unless you're going for an NCRS quality show car.
As for intake duct supports, check these out.
As for exhaust, I think I'm going to try removing the restrictions in the stock unit before going aftermarket (besides the Borla mufflers that are on it). I've got a 2.75" x-pipe coming to replace the restrictive stock resonator, and then I'll probably replace the factory cats with high flow units. The big issues with the stock C4 exhaust to me always seemed to be the restriction right before the cats and resonator where the exhaust necks down. Plus of course the factory resonator.
As for intake duct supports, check these out.
As for exhaust, I think I'm going to try removing the restrictions in the stock unit before going aftermarket (besides the Borla mufflers that are on it). I've got a 2.75" x-pipe coming to replace the restrictive stock resonator, and then I'll probably replace the factory cats with high flow units. The big issues with the stock C4 exhaust to me always seemed to be the restriction right before the cats and resonator where the exhaust necks down. Plus of course the factory resonator.