Air Foil/Spark Plug???
Thread Starter
Instructor
Joined: Apr 2006
Posts: 117
Likes: 1
From: east haven ct.
Air Foil/Spark Plug???
Hello,I was told by a local Vette shop that if you put a air foil,smooth air duct,K/N air filter,Bosch platinum+4 plugs,and performance wires in an L98 you would notice better mileage and all the power you would need accept obvious major mods.Anyone do this or any of the above to their L98.My vette is a 91 thanks.
Team Owner
Joined: Sep 2001
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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better mileage because of all the weight taken out of your wallet
Only plug you need is a Delco Rapidfire, more expensive plugs are just a waste of money. I use MSD 8.5mm wires.
Airfoil-crap
smooth duct-crap
K&N with a cut lid will help.
Only plug you need is a Delco Rapidfire, more expensive plugs are just a waste of money. I use MSD 8.5mm wires.
Airfoil-crap
smooth duct-crap
K&N with a cut lid will help.
Intermediate
Joined: Jan 2006
Posts: 48
Likes: 0
From: national city calif
In my experence, the air foils make a so so paper weight, k&n filters are well worth the money, great air flow, any way you can improve your air flow is a good thing, the bosch plus 4 plugs, couldn't tell any difference from the accel's I had been using, I use the accel 8mm wires, but any good wire should give you excellent service. good luck
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
Originally Posted by vader86
Only plug you need is a Delco Rapidfire, more expensive plugs are just a waste of money. I use MSD 8.5mm wires.
Airfoil-crap
smooth duct-crap
K&N with a cut lid will help.
Airfoil-crap
smooth duct-crap
K&N with a cut lid will help.
Thats what i have now Ac delco RF #5 with MSD 8.5 wires along with K n N cut lid open filter. Air foil and smooth duct are crap, infact i do have smooth duct though very expensive 50 bucks from mid america.
Thread Starter
Instructor
Joined: Apr 2006
Posts: 117
Likes: 1
From: east haven ct.
Air Foil/ Spark Plug???
Thanks for the replies the car runs fine especially since I changed the injectors on July 7.Last August I did a major tune-up and did use the rapid fire plugs.The car runs great (fast) etc.was just wondering about those items see them in catalogs thanks again. Also when the injectors were installed had an adjustable fuel pressure regulator installed.Smooth duct for my car is $69.99 through midamerica.
Last edited by 91quasarblue; Jul 30, 2006 at 10:53 AM.
Safety Car
Joined: Jan 2004
Posts: 3,783
Likes: 15
From: Northern California
On my "91", I use regular AC Delco plugs, MSD wires, K&N with cut lid and a smooth air intake duct I received as a birthday present.
Here's a couple pictures of the K&N with cut lid and the smooth air intake for a "91". The smooth air intake for speed density Vettes looks nice. The smooth air intake for the MAF engines looks like a cheap thin plastic tube.
Here's a couple pictures of the K&N with cut lid and the smooth air intake for a "91". The smooth air intake for speed density Vettes looks nice. The smooth air intake for the MAF engines looks like a cheap thin plastic tube.
Last edited by GKK; Jul 30, 2006 at 01:09 PM.
Safety Car
Joined: Mar 2002
Posts: 3,798
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From: Hattiesburg MS
Originally Posted by vader86
better mileage because of all the weight taken out of your wallet
Only plug you need is a Delco Rapidfire, more expensive plugs are just a waste of money. I use MSD 8.5mm wires.
Airfoil-crap
smooth duct-crap
K&N with a cut lid will help.
Only plug you need is a Delco Rapidfire, more expensive plugs are just a waste of money. I use MSD 8.5mm wires.
Airfoil-crap
smooth duct-crap
K&N with a cut lid will help.
Other than the smooth duct does look good.
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From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Originally Posted by vinnies87
The smooth duct does nothing, as stated many times before, but does look much better than the dirt grabing stock.
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
Originally Posted by vinnies87
The smooth duct does nothing, as stated many times before, but does look much better than the dirt grabing stock.
Le Mans Master
Joined: Apr 2000
Posts: 6,341
Likes: 1
From: Shelton CT
This has been asked many times on the forum, and many people say nay, and few say yay.
I've seen the mods give extra horsepower at the dynos, and if you can think logically, you'll see that most help a bit.. We're not talking the claims the manufacturers claim, but probably 1/2 that.
On a Dyno I've seen these being tested :
K&N with cut lid = around 5-8HP
AirFoil = 6-8HP why do yo uthink new TB's come with this built-in?
High flow powerDuct = No difference
Plugs and Wires = only if your old stuff is bad.
I've seen the mods give extra horsepower at the dynos, and if you can think logically, you'll see that most help a bit.. We're not talking the claims the manufacturers claim, but probably 1/2 that.
On a Dyno I've seen these being tested :
K&N with cut lid = around 5-8HP
AirFoil = 6-8HP why do yo uthink new TB's come with this built-in?
High flow powerDuct = No difference
Plugs and Wires = only if your old stuff is bad.
Thread Starter
Instructor
Joined: Apr 2006
Posts: 117
Likes: 1
From: east haven ct.
Originally Posted by MrNuke
This has been asked many times on the forum, and many people say nay, and few say yay.
I've seen the mods give extra horsepower at the dynos, and if you can think logically, you'll see that most help a bit.. We're not talking the claims the manufacturers claim, but probably 1/2 that.
On a Dyno I've seen these being tested :
K&N with cut lid = around 5-8HP
AirFoil = 6-8HP why do yo uthink new TB's come with this built-in?
High flow powerDuct = No difference
Plugs and Wires = only if your old stuff is bad.
I've seen the mods give extra horsepower at the dynos, and if you can think logically, you'll see that most help a bit.. We're not talking the claims the manufacturers claim, but probably 1/2 that.
On a Dyno I've seen these being tested :
K&N with cut lid = around 5-8HP
AirFoil = 6-8HP why do yo uthink new TB's come with this built-in?
High flow powerDuct = No difference
Plugs and Wires = only if your old stuff is bad.
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
[QUOTE=GKK]On my "91", I use regular AC Delco plugs, MSD wires, K&N with cut lid and a smooth air intake duct I received as a birthday present.
Here's a couple pictures of the K&N with cut lid and the smooth air intake for a "91". The smooth air intake for speed density Vettes looks nice. The smooth air intake for the MAF engines looks like a cheap thin plastic tube.
Looks great! I too want to get the smooth flow duct for the looks as well as my stock one is beat and truely needs to be replaced!
I use an Air Foil and I will take arrow dynamicly shaped intake over the flat inlet any day on the TB.
I use K&N and an open air lid. I use Bosch +2's(Did not notice any difference w/these) and Moroso 8mm spiral wires.
If your parts are old and worn then you certainly will feel and notice a difference in the gas mileage and performance.
Thanks,Matt
Here's a couple pictures of the K&N with cut lid and the smooth air intake for a "91". The smooth air intake for speed density Vettes looks nice. The smooth air intake for the MAF engines looks like a cheap thin plastic tube.
Looks great! I too want to get the smooth flow duct for the looks as well as my stock one is beat and truely needs to be replaced!
I use an Air Foil and I will take arrow dynamicly shaped intake over the flat inlet any day on the TB.
I use K&N and an open air lid. I use Bosch +2's(Did not notice any difference w/these) and Moroso 8mm spiral wires.
If your parts are old and worn then you certainly will feel and notice a difference in the gas mileage and performance.
Thanks,Matt
Pro
Joined: Apr 2006
Posts: 747
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From: Perth Western Australia
Ive done all those 'free' mods, air foil, power duct, k&n, open air box, coolant bypass, air temp sensor move and ive found that they do help to some degree on an other wise stock engine.
ok, so my test was using a g-tech metre.... i know how some feel about that device, but the tests were done on the same stretch of road, same time of day.... and very similar temperatures to each other.
the g-tech claimed that 0-60miles without mods was a pretty consistent 6.2 sec.
then with mods the times went down to a consistent 5.7 sec time.
half a second aint too bad
fuel mileage i cannot say whether it got better or not, as i dont drive 'nicely' or consistent enough to get an accurate reading.
ok, so my test was using a g-tech metre.... i know how some feel about that device, but the tests were done on the same stretch of road, same time of day.... and very similar temperatures to each other.
the g-tech claimed that 0-60miles without mods was a pretty consistent 6.2 sec.
then with mods the times went down to a consistent 5.7 sec time.
half a second aint too bad
fuel mileage i cannot say whether it got better or not, as i dont drive 'nicely' or consistent enough to get an accurate reading.
Le Mans Master
Joined: Apr 2000
Posts: 6,341
Likes: 1
From: Shelton CT
Originally Posted by Lichen
6-8 hp from an airfoil? 
I did all those bolt ons on a stock '85 L98, and with the addition of a performance chip (perf resources), and SLP ram air, the car went from 14.0-14.1@96 to 13.7-13.8@98-99.. If you do the math, it all adds up actually. But... That of course warranted going even faster, and spend more money on more mods.. LOL
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
I had a airfoil on my 86 when I purchased it. It idled rough and I tried to troubleshoot the problem. After much work I decided to remove the airfoil and "WOW" the idle improved a lot. Got to looking at the airfoil and the U shaped groove at the bottom of it was too small and blocking air flow to the IAC.
Only thing good is to get a K&N and cut the vents off the air lid. The other items suggested are a waste of money. Most all spark plugs are/do the same thing. Go with a good choice of plugs and wires. The airfoil is a good item to give to someone else (crap).
Only thing good is to get a K&N and cut the vents off the air lid. The other items suggested are a waste of money. Most all spark plugs are/do the same thing. Go with a good choice of plugs and wires. The airfoil is a good item to give to someone else (crap).