K&N Intake - why the cutting?
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
You don't have to cut the shroud unless you want cold exterior fresh air to enter the hot engine compartment. Even with Z06 type screens or altered fog light surrounds, the intake can only draw so much cooler air from the outside. The cut shroud maximizes the effect, especially with forward movement.
If you install with the filter sitting on top of the uncut shroud, you have essentially a cooler air intake (just like a BLACKWING, HALLTECH or many other similar products).
If you install with the filter sitting on top of the uncut shroud, you have essentially a cooler air intake (just like a BLACKWING, HALLTECH or many other similar products).
Last edited by hotwheels57; Jul 9, 2007 at 05:40 PM.
Burning Brakes
Joined: Nov 2006
Posts: 961
Likes: 0
From: Torrance CA
You don't have to cut the shroud unless you want cold exterior fresh air to enter the hot engine compartment. Even with Z06 type screens or altered fog light surrounds, the intake can only draw so much cooler air from the outside. The cut shroud maximizes the effect, especially with forward movement.
If you install with the filter sitting on top of the uncut shroud, you have essentially a cooler air intake (just like a BLACKWING, HALLTECH or many other similar products).
If you install with the filter sitting on top of the uncut shroud, you have essentially a cooler air intake (just like a BLACKWING, HALLTECH or many other similar products).
Intermediate
Joined: Oct 2003
Posts: 49
Likes: 0
From: Prince Frederick MD
Talk about timing. I just installed one on my 99 C5 this morning. I was very hesitant to cut the shroud, but as stated above, if you don't, it won't fit under the hood. I followed the directions to the letter, and everything went OK. Took about two hours. Cutting the shroud was the most time consuming. I used a 12-inch ruler, looking at the shroud from the opening in the hood from the front to make the 1/2 inch measurements on the top and side. One thing they do not make clear is do not cut the top vertical line on the shroud. You will make a total of three cuts: two sides and one along the bottom. The flap you cut will then fit the angle brackets provided in the kit. I drove the car afterward, and although there is debate on the forum that there is minimal HP increase, the car felt faster - maybe psychological! The shrouds are available as aftermarket, as the one I took off was a replacement piece. I only learned after I bought the car last month that it was involved in a front collision some time back, so the shroud was replaced. Hope this helps.
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
Wow, I didn't realize the K&N FIPK was that much taller than the oem air bridge. I had a complete BLACKWING system, cut shroud with after market air bridge and "ice box" cover on my Z16 for a while. I know the after market air bridge was a tight fit under the hood insulator. I went back to the oem Z16 intake assembly with a drop in K&N and enlarged the opening to the top cover. Works as good as the BLACKWING and no darn intermittent codes.
Banned Scam/Spammer
Joined: Jul 2006
Posts: 2,911
Likes: 10
From: Simi Valley CA
I didn't cut mine either. The only problem was the angle of their bridge was off which meant the intake hoses they provided didn't quite work. I ended up using the stock air bridge, some intake hose from intakehoses.com and a couple of nitrous nozzles for that 'FRESH COLD AIR INTAKE" system. 
Burning Brakes
Joined: Nov 2006
Posts: 961
Likes: 0
From: Torrance CA
most likely not, as most manufacturers claims are false.
but I did feel a slight difference in throttle response, It makes an awesome "sucking" noise, and it looks really cool under the hood.
Was worth the money and installation time IMO.
but I did feel a slight difference in throttle response, It makes an awesome "sucking" noise, and it looks really cool under the hood.
Was worth the money and installation time IMO.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Thread Starter
Drifting
Joined: Jun 2007
Posts: 1,437
Likes: 5
Hey Guys...
I must admit, looking at the instructions it's not quite clear to this NooB what the heck they are cutting! I'm really thankful to NOS500 for the 3 cut only tip!
Just to calrify...when you make the 3 cuts, I can envision the plastic flap opening downward and held in place by the brackets they provide? And I guess that's just about a 1 inch gap/opening to let cool air in?
This forum really is the best!
-al
I must admit, looking at the instructions it's not quite clear to this NooB what the heck they are cutting! I'm really thankful to NOS500 for the 3 cut only tip!
Just to calrify...when you make the 3 cuts, I can envision the plastic flap opening downward and held in place by the brackets they provide? And I guess that's just about a 1 inch gap/opening to let cool air in?This forum really is the best!
-al
7th Gear
Joined: Jul 2014
Posts: 7
Likes: 0
From: Jacksonville FL
Given the better air flow of the k & n, the smooth connection of the air bridge to the throttle body instead of the stock accordian hose and the larger volume of the air bridge, the k & n would have to be an airflow improvement over stock even without cutting the radiator shroud. Just my humble opinion and my install. Lol
Melting Slicks
Joined: Feb 2014
Posts: 2,725
Likes: 149
From: chicago area IL.
not sure what site that was on but I looked it up and got this one 11.35hp / 12.93tq witch i personally think is more believable 18+ hp from a intake is a lot for me to be leave (with out tuning)
http://b.cdnbrm.com/images/info/k_n/dyno_63-1050.pdf
http://b.cdnbrm.com/images/info/k_n/dyno_63-1050.pdf
7th Gear
Joined: Jul 2014
Posts: 7
Likes: 0
From: Jacksonville FL
not sure what site that was on but I looked it up and got this one 11.35hp / 12.93tq witch i personally think is more believable 18+ hp from a intake is a lot for me to be leave (with out tuning)
http://b.cdnbrm.com/images/info/k_n/dyno_63-1050.pdf
http://b.cdnbrm.com/images/info/k_n/dyno_63-1050.pdf
the 63-1050 dyno is a Z06 specific dyno which you'll see less of a gain because the breathing and other things are already inhanced on the Z06.
basically the same CAI but on 2 different engines
Melting Slicks
Joined: Jul 2004
Posts: 3,092
Likes: 120
From: orlando florida
St. Jude Donor '15
not sure what site that was on but I looked it up and got this one 11.35hp / 12.93tq witch i personally think is more believable 18+ hp from a intake is a lot for me to be leave (with out tuning)
http://b.cdnbrm.com/images/info/k_n/dyno_63-1050.pdf
http://b.cdnbrm.com/images/info/k_n/dyno_63-1050.pdf
http://www.knfilters.com/mobile/mPro...?&prod=57-3020
The one you posted is just above the one I posted 2000 corvette
Looking at that page the 97-2000 all show 18.29 hp and 00-04 show 11.35 hp
Last edited by mrr23; Dec 4, 2014 at 12:49 PM.
Melting Slicks
Joined: Jul 2004
Posts: 3,092
Likes: 120
From: orlando florida
St. Jude Donor '15
the 57-3020 dyno is from a 1999 non Z06 5.7L vette which may see that much increase.
the 63-1050 dyno is a Z06 specific dyno which you'll see less of a gain because the breathing and other things are already inhanced on the Z06.
basically the same CAI but on 2 different engines
the 63-1050 dyno is a Z06 specific dyno which you'll see less of a gain because the breathing and other things are already inhanced on the Z06.
basically the same CAI but on 2 different engines
Melting Slicks
Joined: Feb 2001
Posts: 2,804
Likes: 358
From: Northville, MI
When looking at comparisons with Dyno results you always have to look at what type of dyno was used. What is impressive is in 1999 there was VERY little tuning available and most of the ones available were not that well developed. Today you should see those types of gains and more with the advances in tools and learning curve of those doing the tuning. Turning the vette into a bottom breather will show better results when the car is moving and encapsulating the filter on the shroud will help even more. Still you will probably not see more than 20-25 hp gains. The hp gain is getting cooler air into the cylinder head and Denser and can contain more fuel in the engine chamber. Going to a smoother coupler couple doesn't help to any degree since the firmware in the PCM was established to compensate for it. When you add head, cam, headers, etc, then you will see greater gains.
mike v
Joined: Feb 2013
Posts: 465
Likes: 92
From: Riner Va
On my 01 coupe I have install an Aluminum Duel Air Intake with the Power Coupler.
With only the Duel Air Intake fuel mileage was the same. When I added the Power
Coupler I lost apmx. 3 to 4.5 miles to the gal. high way and Black-er EX. tips.. Read on the forum that because of all the smooth air entering the TB the PCM ?? thinks the Engine is running leaner??.. I spoke with a C5Z - CF member from Conn. who suggested a Comp tune from one of the mail it too folks. BUT,, thought I would wait for the new tune, until I get my Ported & Polished TB. Back.
Has any one else noticed or needed a tune just with the smooth Coupler installed ???
With only the Duel Air Intake fuel mileage was the same. When I added the Power
Coupler I lost apmx. 3 to 4.5 miles to the gal. high way and Black-er EX. tips.. Read on the forum that because of all the smooth air entering the TB the PCM ?? thinks the Engine is running leaner??.. I spoke with a C5Z - CF member from Conn. who suggested a Comp tune from one of the mail it too folks. BUT,, thought I would wait for the new tune, until I get my Ported & Polished TB. Back.
Has any one else noticed or needed a tune just with the smooth Coupler installed ???
Melting Slicks
Joined: Jun 2013
Posts: 3,473
Likes: 691
From: West Virginia
Don't know if they still do, but their web site used to show dyno pull results. That's how I found that the very early cars respond better to a free flowing intake than the later ones. Have to say, I probably believe those guys much more than many of the "added power" claimants, especially the exhaust guys. Aftermarket exhausts may sound and look better, but that's about it.
BTW, you cut the shroud to give clearance to the filter so airflow is not obstructed at the bottom.
BTW, you cut the shroud to give clearance to the filter so airflow is not obstructed at the bottom.
