Free Extra Horse Power
Thread Starter
Melting Slicks
Joined: Jun 2006
Posts: 2,923
Likes: 1
From: Cleveland Tennessee
Free Extra Horse Power
I have read from a very qualified and educated man about the amount of air that is let in on a stock air filter lid on some C4 Corvettes through the louvered vents/slots is just over 25 square inches of area. When you take off the shroud cover and cut the lid open around the five rivet holes that connect the shroud then the air inlet amount changes to more then 85 square inches of air inlet area. That is a huge increase. He also said that he had a verified dyno test done for a stock engine difference and a modified engine difference with these two stock and cut open air lid covers. The stock engine with the open lid got 2 more HP, and the modified engine got 11 more HP, either is a good addition for just cutting the lid open and letting your LT1 breath better and more. So here are the pictures of mine before and after, on my 383 stroker LT1.
Thread Starter
Melting Slicks
Joined: Jun 2006
Posts: 2,923
Likes: 1
From: Cleveland Tennessee
I got the information for another member here that had his own website/webpage where he was talking about all the other type of useless things that people get talked into getting like airfoils, airtemp relocators, and other things that are really not getting you what they claim. I will see if I can find that site again and post the site, it had some intersting information, I'm sure that if you are a member here for a while you probably know whom I am talking about, and like I said he said he had dyno pulls denoteing the differences, I also realize that most people here probably already do have the cutout lid, but I thought for those that do not or don't know it might be good information.
Team Owner
Joined: Sep 2002
Posts: 22,209
Likes: 12
From: OBAMA IS HITLER
i've always said that, i agree, the "free" or ultra cheap mods are great for feeling good, but they don't actually do any good. you might see a couple hp on the dyno, but to me a dyno is numbers on a piece of paper -- cute for pounding your chest and bragging off, but not much else.
Race Director
Joined: Nov 2000
Posts: 10,343
Likes: 668
From: Beverly Hills (Pine Ridge) Florida
Have done back to back to back runs with it, and without it, plus using a K&N, no filter (actually used just a gauze to catch the bigger stuff), and stock type filter.
This was with a basically stock 87 TPI (heads and manifolds ported, & screen removed).
Absolutely no difference with any of them.
Perhaps on a highly modified engine it might make a difference.
Plasticman
This was with a basically stock 87 TPI (heads and manifolds ported, & screen removed).
Absolutely no difference with any of them.
Perhaps on a highly modified engine it might make a difference.
Plasticman
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Le Mans Master
Joined: Jul 2000
Posts: 7,639
Likes: 326
From: Greenville SC
Well I do apprecaite the info. I have had mine done for years, and so have many others, but I have never heard of any dyno proof etc. Do you think you could post the graphs, and get the info. of what the modified engine consisted of mod wise?
Elite Torch Red Member
Joined: Sep 1999
Posts: 57,805
Likes: 23
From: Exit 89 GSP,Lakewood,NJ The Land Of Mojo
Cental/South NJ Events Coordinator
CI 1-2-3-4-5-6-7-8-9-10-11-12 Vet
CI-II Burnout & Drag Champ
St. Jude Donor '03-'04-'05-'06-'07
Opening the lid on a stock LT1 does nothing, I have several hundred time slips from the track that show no difference.
As Mr Mackey always told me, it doesn't matter how much air you draw in because the throttle body opening is still the same size.
There had to be a reason it was designed the way it was, and I'm sure it wasn't to detune the car.
BTW, there is a diference in the lids between my '95 and my '93 and I measured the openings between the two and they were the same. Only difference was that the '95 lid draws air in from the front/top and the '93 from the sides.
As Mr Mackey always told me, it doesn't matter how much air you draw in because the throttle body opening is still the same size.
There had to be a reason it was designed the way it was, and I'm sure it wasn't to detune the car.
BTW, there is a diference in the lids between my '95 and my '93 and I measured the openings between the two and they were the same. Only difference was that the '95 lid draws air in from the front/top and the '93 from the sides.
Bench Racer
Joined: Feb 2003
Posts: 4,201
Likes: 15
From: Palm Beach Gardens FL
St. Jude '03 thru 14,'25
Originally Posted by Mr Mojo
...I measured the openings between the two and they were the same. Only difference was that the '95 lid draws air in from the front/top and the '93 from the sides.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by Mr Mojo
Opening the lid on a stock LT1 does nothing, I have several hundred time slips from the track that show no difference.
As Mr Mackey always told me, it doesn't matter how much air you draw in because the throttle body opening is still the same size.
There had to be a reason it was designed the way it was, and I'm sure it wasn't to detune the car.
BTW, there is a diference in the lids between my '95 and my '93 and I measured the openings between the two and they were the same. Only difference was that the '95 lid draws air in from the front/top and the '93 from the sides.
As Mr Mackey always told me, it doesn't matter how much air you draw in because the throttle body opening is still the same size.
There had to be a reason it was designed the way it was, and I'm sure it wasn't to detune the car.
BTW, there is a diference in the lids between my '95 and my '93 and I measured the openings between the two and they were the same. Only difference was that the '95 lid draws air in from the front/top and the '93 from the sides.
Safety Car
Joined: Sep 2000
Posts: 3,524
Likes: 4
From: Hinckley Ohio
Originally Posted by bogus
My thinking is more along the lines that the TB isn't the restricting factor, but the entire engine. We all know the TB can flow a helluva lot more than the engine can...
This is probably true for a stock LT1, but when the mods start an upgraded TB should be part of the mods for maximum performance.
Le Mans Master
Joined: Aug 2003
Posts: 9,884
Likes: 3
From: Magnolia Mississippi
St. Jude '03-'04-'05-'06-'07
Originally Posted by bogus
To be polite, telling this group about the cut air lid is akin to informing the general public the sky is blue... sorta like preaching to the choir...
amend to that one.... years too late
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by LT4BUD
[/B]
This is probably true for a stock LT1, but when the mods start an upgraded TB should be part of the mods for maximum performance.
This is probably true for a stock LT1, but when the mods start an upgraded TB should be part of the mods for maximum performance.
Racer
Joined: Apr 2004
Posts: 487
Likes: 0
From: Huntsville AL
It flows this, it flows that, it's on a 502, it's on a ZR-1 (I think), blah blah blah. All I know is it made a big difference on my car and I still have stock heads and stock cam. I think 291rwhp is proof enough for me that it helps a lot when you have long tube headers and a free flowing exhaust on a LT-1. I've track tested every mod I've ever done, time slips don't lie.