Switching trunk lids for downforce on the track/DD car?

[JonnyTrauma]

Does anyone have a second trunk lid with aero for track use? I was going to try to get an e46 M for a dedicated track car but it's just not in the cards right now. I am going to do some work on my e92 over the winter to make it more track friendly and I intend on doing a few time trials next season.

I am thinking about the following combo:

http://store.bimmerworld.com/bimmerw...wing-p906.aspx

http://www.bimmian.com/OEM-&-CSL-Sty...r-E93-3-Series (OEM version)

Does anyone here swap trunk lids for the track? How much of an effect did the aero have on your lap times? How difficult is it to swap? Do you have to reinforce the lid down to the frame for it to be effective? I have to lift going into the penultimate turn onto the straight at NJMP Thunderbolt (my closest track) and anything with downforce grabs a few seconds on me by the end of the straight. I think DF would alleviate that. Any feedback appreciated.

Thanks

[1MOREMOD]

unless you have already extracted every last tenth of a second in other ways dont think aero is necessary. get the most out of your suspension, brakes, alignment, and weight loss program first. at least thats my feeling.

[warp10]

user: 4sevens.com has two trunks for street and track on his e90 m3

[OC3]

I know a handful here in SoCal who runs aero, and I don't think they swap the trunk before & after each track days. Too much work/trouble.

As for time, for the same car & same driver, I think aero is good for 2~3 second faster lap times.

As for reinforcement, I think the mounts that are positioned closed to the middle require reinforcement due to the trunk lid flexing, which is why you see majority of the mounts positioned at the outer edges of the trunk lid.

Anyhow, if you go w/ a wing, don't forget to consider a (deep) splitter at the front and may be even supplement that with canards. With wing only, you run at extreme speeds, the rear wing presses down but there's nothing at the front pressing down, so the car lifts at the front...

[pkimM3r]

You can leave the mounts on when dailying and then put the big ass wing at the track.

[Billj747]

Originally Posted by OC3

I know a handful here in SoCal who runs aero, and I don't think they swap the trunk before & after each track days. Too much work/trouble.

As for time, for the same car & same driver, I think aero is good for 2~3 second faster lap times.

As for reinforcement, I think the mounts that are positioned closed to the middle require reinforcement due to the trunk lid flexing, which is why you see majority of the mounts positioned at the outer edges of the trunk lid.

Anyhow, if you go w/ a wing, don't forget to consider a (deep) splitter at the front and may be even supplement that with canards. With wing only, you run at extreme speeds, the rear wing presses down but there's nothing at the front pressing down, so the car lifts at the front...

I agree but cars generally need more rear df than front. There's nothing wrong w.just running a wing. It will still make a big difference.

[dmw16]

Originally Posted by 1MOREMOD

unless you have already extracted every last tenth of a second in other ways dont think aero is necessary. get the most out of your suspension, brakes, alignment, and weight loss program first. at least thats my feeling.

This. If you're still at the point where you are steering your track car (at least beyond to/from track) aero is probably overkill.

I'd imagine you are leaving time elsewhere on the track. What are you lap times?

To me, aero is the last step.

[OC3]

Originally Posted by Billj747

I agree but cars generally need more rear df than front. There's nothing wrong w.just running a wing. It will still make a big difference.

Yeah, but with just the wing, I think the front end will get a bit lighter and therefore possibly understeer a bit. So, probably a good idea to put something on the front too.

What's your opinion on wing mounts being outside versus closer to the center?

[bigjae1976]

What a massive PIA switching trunk lids. Brakes, camber, harnesses, checking out the car...oh...I have to switch trunk lids. Unless you're paying someone to do all of this work I wouldn't bother.

How much of a difference will it make? Don't know.

[pkimM3r]

Originally Posted by bigjae1976

What a massive PIA switching trunk lids. Brakes, camber, harnesses, checking out the car...oh...I have to switch trunk lids. Unless you're paying someone to do all of this work I wouldn't bother.

How much of a difference will it make? Don't know.

Crap just reminded of camber plates. Switching wheels and pads is enough already. I guess can do jack front of car, take wheel off, swap pads, change camber and put track wheel on. Thats the easy part hard part is after a track day. Yikes!

[Groundpilot]

Swap trunk lid for the track? I just installed CSL style trunk lid on my m3 and let me tell you that it is a PITA. Not that difficult but it takes a lot of time. Looks much better than stock and it will stay that way.
Selling my stock trunk lid now.

[USCTrojanMan29]

Originally Posted by Billj747

I agree but cars generally need more rear df than front. There's nothing wrong w.just running a wing. It will still make a big difference.

Question for you....how much benefit would I get for my car (997.2 GT3) if I put on a bigger Porsche Motorsport cup car wing ($8k cost)? I was thinking maybe the 997.2 GT3RS wing and decklid because it's more streetable but the cost is beyond high ($12k-$14k for wing, end plates, decklid, and intake).

[Billj747]

Originally Posted by OC3

Yeah, but with just the wing, I think the front end will get a bit lighter and therefore possibly understeer a bit. So, probably a good idea to put something on the front too.

What's your opinion on wing mounts being outside versus closer to the center?

The balance will depend on the whole setup: how big of a wing and what angle of attack, tire size/compound/stagger, spring rates, swaybars, etc...

You don't NEED a front splitter in order to have a wing. Even with just a wing, the car will be quicker around a track than no wing. You can adjust the wing for the correct balance, or change other aspects of the setup to balance it out. If you do have a splitter, then you can afford to add even more rear downforce. In general, pretty much every car will require a lot more rear downforce relative to front.

I think there's more strength for a stock trunklid to have the mounts on the outer edges. For efficiency purposes, the uprights should be thin and parallel to eachother -but this is insignificant in the grand scheme of things for most people.

Originally Posted by USCTrojanMan29

Question for you....how much benefit would I get for my car (997.2 GT3) if I put on a bigger Porsche Motorsport cup car wing ($8k cost)? I was thinking maybe the 997.2 GT3RS wing and decklid because it's more streetable but the cost is beyond high ($12k-$14k for wing, end plates, decklid, and intake).

Your stock wing is already making a good amount of downforce. From a quick search, you're making 20Kg (44lbs) of downforce at 120mph while the RS makes 50Kg (110lbs) and the GT3 Cup wing is adjustable and can vary a ton -like the RS wing, but I'd suspect it's 1.5-2X the RS' downforce #.

http://bigmike.marlincrawler.com/for...php?topic=33.0
http://nzhondas.com/pub/112100-inter...road-cars.html

How much do you track your car? What tires are you using? I like the cup wing, and while cool on a track, it might stick out as 'boy-racer' on the street. Then again, while the RS's wing is more 'streetable', it's still very bold. Then again, it's a GT3 so it's justified either way. I think the RS wing is the best value unless there's a different manufacturer out there with a similar wing as a Cup car which should cost less than half of that $8K figure.

[USCTrojanMan29]

Originally Posted by Billj747

Your stock wing is already making a good amount of downforce. From a quick search, you're making 20Kg (44lbs) of downforce at 120mph while the RS makes 50Kg (110lbs) and the GT3 Cup wing is adjustable and can vary a ton -like the RS wing, but I'd suspect it's 1.5-2X the RS' downforce #.

http://bigmike.marlincrawler.com/for...php?topic=33.0
http://nzhondas.com/pub/112100-inter...road-cars.html

How much do you track your car? What tires are you using? I like the cup wing, and while cool on a track, it might stick out as 'boy-racer' on the street. Then again, while the RS's wing is more 'streetable', it's still very bold. Then again, it's a GT3 so it's justified either way. I think the RS wing is the best value unless there's a different manufacturer out there with a similar wing as a Cup car which should cost less than half of that $8K figure.

I take my car out to the track like one a month on average. I'm currently running NT01s on 18" CCW wheels with a 5-wheel stud conversion from the CLs. I love the look of the GT3RS wing, but the cost is definitely steep. The $8k for the Motorsport set-up includes both the end plates and the decklid (no intake change is required like for the OEM GT3RS wing set-up). My skill level is in the high intermediate/low advanced level at this point so it's not like the wing is a must have now but it is in the back of my mind.

[Billj747]

Originally Posted by USCTrojanMan29

I take my car out to the track like one a month on average. I'm currently running NT01s on 18" CCW wheels with a 5-wheel stud conversion from the CLs. I love the look of the GT3RS wing, but the cost is definitely steep. The $8k for the Motorsport set-up includes both the end plates and the decklid (no intake change is required like for the OEM GT3RS wing set-up). My skill level is in the high intermediate/low advanced level at this point so it's not like the wing is a must have now but it is in the back of my mind.

Depends on your budget and what you want to do with the car. Either the GT3RS or the Cup wings will make a bit more downforce and the car will be more stable and faster. But there's nothing wrong with leaving it the way it is either.

[bigjae1976]

I know a couple who has a 996 GT3RS and they actually prefer the less aggressive wing and front lip. The bigger stuff (cup wing and lip???) made the car understeer more than they liked...but this couple are a little crazy as well...

This is all second hand info though. I don't drive Porsches.

[Shaung]

Don't be afraid we're behind you 100% for drilling holed in your trunk!

[dapopa9]

Depending on what Wing you go with you could just keep the same trunk lid on and just unbolt the wing while not on the track.