What is the best air intake for a 2010 Grand Sport Coupe with an LS-3. What can I expect as far as HP gain and gas mileage improvement?

 

Threads like this pop up weekly and everyone has an opinion. Without regurgitating everyone's opinions on every unit you might want to figure out your budget and do some searching.

I recommend the stock unit. It works well and looks factory (imagine that).

 

 

Get the Attack Blue. You dont need to change out the whole unit, just the restricted filter.

 

I'm running the stock air intake with the factory paper filter on my Z06. You have basically the same intake on your Grand Sport. It feeds you plenty of air. When I need to replace the original paper filter, I will install the ZR1 paper filter, as it does flow more air then the filter used in the LS3/LS7.

I did install a Vette-Air scoop to get aditional cooler outside air through the grille to the intake, but it requires, in my opinion, a diffuser to keep the intake air turbulence under control. I made my diffuser from a piece of 1/8" Plexiglas, 18" long X 3.5" wide, sealed to the bumper beam with a piece of slit vacuum hose and the ends of the back edge of the diffuser contoured to fit the shroud with around 1/4"-3/8" clearance, for the 4" on each end. The diffuser is mounted to the top of the Vette-Air scoop utilizing the rear two bolts. It's purpose is to keep the incoming rush of air from directly hitting the paper filter. I originally tried the Attack Blue filter in conjunction with the Vette-Air, and had all kinds of problems with air turbulence across the MAF, setting codes and turning on the CEL. I sold the Attack Blue filter.

 

I'm thinking of going this way too when my Z06 filter nears end of life. There was a comparison with all 3 filters (Z06/ZR1/AB) done by a forum member and the ZR1 filter actually beat out all others on the dyno. (gains were only like 4-5hp though)

 

For the most gain in real world driving conditions (ie, NOT on the dyno).....Vararam

 

I have checked in my '09 owners manual and it shows the EXACT same part number for the air filter for the LS3 and the LS7. Must flow really well to feed a 505hp ZO6 so should be more than enough for the LS3.

 

yes and it's a Donaldson so one of the best there is
another forum member did a temp test and found that air temps were close to outside air with the stock intake!
just not much improvement to be had.

 

For $2 in hdwe to prop open the shroud, you'll gain about .15 sec and 2 mph in the 1/4 while retaining excellent filtration.
For $450 with the Vararam, gains are about .25 sec and 3 mph, however the filtration suffers.
Not much else has real world track testing, but many butt dyno opinions.

MPG is mostly related to the right foot, not the air intake.

 

Can you go into that $2 prop open shroud in more detail?

 

The bottom front of the shroud is held in place by two plastic snap-in push pins toward the center. Pull those out and the shroud can be propped open to easily let outside air directly in to the filter.

Hardware consists of two 5" long 1/4-20 pieces of allthread, eight 1/4-20 nuts, and four 1/4 x 1 fender washers.

Put 4 nuts on each allthread near the center and then a washer on each side. Spread the shroud open and insert one end of the allthread in the shroud hole and the other end in the metal frame hole where the shroud was attached. Do that on the other side too. Then start running the nuts away from each other (2 one way & 2 the other) to spread the shroud open to about a 3" space. Then tighten the pairs of nuts against each other (aka jam nut) to hold the position. There will will be more than enough tension to hold the washers in place and not have any fear of the whole part falling out.

You can install this in 10 minutes and return it to stock in half that time.

I did this to a friend's LS2 at the track. He had made 2 back to back passes at 12.38 and was happy, as that was a PB. 15 minutes later after the shroud prop, he ran a 12.22 and then a 12.23. The trap speeds were 2 mph faster too. Ya shouda seen the smile then.

 

The airbox and MAF are completely different between the LS2 and LS3/7. If you open up the shroud on the LS3/7 and have air directed directly into the paper element, you will most likely hurt performance, as you will induce unwanted air turbulence to the MAF. GM has a TSB directing the tech to check and make sure the shroud is sealed to the front bumper beam if a car is brought in and the owner is complaining about surging.

 

I had that mod on my LS3 for several weeks before going to a Vararam and I did have some surging initially, which slowly stopped after 30-50 miles. My 1/4 mile times showed roughly the same improvement as the LS2. The design of the Donaldson filter straightens the airflow far more than any other filter, so turbulence is not an issue. Because of having lots of timeslips relating to all sorts of mods, the real world experience and documentation is what qualified me to make the previous statements.

 

if you are not racing the Vette, leave it stock and save your money cus you won't notice much in either area.

 

In my opinion, Airaid can not be beaten. In addition to making as much power as any of the other aftermarket units we've used they have superior engineering and construction with an OEM look and fit.

 

GM is also very qualified to write a tsb when air leakage around the shroud/bumper beam occurs(which is what you are doing with your MOD), causing surging and sets codes/CEL.



#PIP4319A: Corvette Lean DTCs P0171 P0174 - keywords 6.2 7.0 ECM engine fuel HO2S injector LS3 LS7 MAF MAP MIL o2 pressure sensor SES - (May 1, 2008)


Subject: Corvette Lean DTCs P0171 P0174


Models: 2007-2008 Chevrolet Corvette




--------------------------------------------------------------------------------

This PI was superseded to advise dealers of repair information. A loose close-out panel and holes in frame plate may disturb intake air flow. Please discard PIP4319.

Condition/Concern:
A dealer may encounter a customer concern of the SES light on with DTCs P0171 P0174 found.

If the air flow to the Air Intake/Air Cleaner Assembly is disturbed, DTCs P0171/P0174 may be induced.

Recommendation/Instructions:
DTCs P0171/P0174 may be caused by a gap between a body close out panel combined with some frame plate holes. The close-out panel gap and frame plate holes may cause an air flow disturbance to Air Intake/Air Cleaner Assembly (please see attached pictures for a better description).

This is a picture of a close-out panel with a good fit (item number 2), and the frame plate holes (item number 1) that need to be covered with a good adhesive type patch (sound deadener patch) or equivalent. Sound deadener patches can be obtained from Kent Automotive. Kent Automotive can be contacted at 1-888-YES-KENT (www.kent-automotive.com) to obtain Kent part number: P20617.

Clean the frame plate as necessary and install the patch so the holes (item number 1) are covered. No air can flow through these holes.

Evaluate the lean condition after the close-out panel gap has repaired, and frame plate holes have been covered.

Note: Any modifications to the Air Intake/Air Cleaner Assembly must be removed before attempting repairs for the lean condition.

 

I'm not arguing about a TSB, but simply noting the real world results of a particular mod on both an LS2 and LS3. GM writes TSB's for factory stock cars. The cars I have first hand track experience with are modified. The car GM built for me ran mid-twelves bone stock. With my mods, the car now runs mid-elevens. I don't believe that hurt the performance.

The OP asked for air intake information in an attempt to gain knowledge before modifying his car and I gave him two options with my personal results. If you have had different experiences and documented results with air intake systems, I suggest you share them.

 

I did share my experiences, post #5, as I also did a "cold air" MOD to my 09 Z06. My results mirrored the problem GM addressed in their TSB when air is directed into the air breather from the lower shroud/bumper beam area. Also re-read the last sentence of the TSB "Note: Any modifications to the Air Intake/Air Cleaner Assembly must be removed before attempting repairs for the lean condition". Wonder why GM put that sentence in their TSB? Could it be because they know a little about MODs to the air intake and how they can negatively affect the cars performance.

Sorry, GM's engineering expertise trumps your "Buba" expertise. I suggest you do a search on this forum for "surging" and see what others have to say. Like you, I have some experience in real world MODs to a stock car. I haven't run my car at the drag strip, don't plan to. But, if I can't drive it to the drag strip without surging and setting codes, what have I achieved?

My post #5,

"I'm running the stock air intake with the factory paper filter on my Z06. You have basically the same intake on your Grand Sport. It feeds you plenty of air. When I need to replace the original paper filter, I will install the ZR1 paper filter, as it does flow more air then the filter used in the LS3/LS7.

I did install a Vette-Air scoop to get additional cooler outside air through the grille to the intake, but it requires, in my opinion, a diffuser to keep the intake air turbulence under control. I made my diffuser from a piece of 1/8" Plexiglas, 18" long X 3.5" wide, sealed to the bumper beam with a piece of slit vacuum hose and the ends of the back edge of the diffuser contoured to fit the shroud with around 1/4"-3/8" clearance, for the 4" on each end. The diffuser is mounted to the top of the Vette-Air scoop utilizing the rear two bolts. It's purpose is to keep the incoming rush of air from directly hitting the paper filter. I originally tried the Attack Blue filter in conjunction with the Vette-Air, and had all kinds of problems with air turbulence across the MAF, setting codes and turning on the CEL. I sold the Attack Blue filter."

 

Vararam.