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Anyone who has experience tracking their Elise or participating in autocrosses, can you let me know if the tracks require the Elises to have hardtops, as I will be making my final options soon and placing my order. Initially I was not going to order the hardtop because I live in California thus no harsh winters, but if it is a requirement then I will get it.
Also, does driving with the hardtop on at highway speeds lower the amount of wind noise noticeably?? When I test drove the car I did not get a chance to drive it on the highway although I did get it up to 85mph on the side street, but was too excited by the experience to notice the wind noise.
 

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For autocross under SCCA rules, you won't need a hardtop. The only important restriction for open cars is that you can only use upper body restraints if the top of your helmet isn't higher than the roll structure (aka the "broom stick test"). Here is a document that spells out this rule in some more detail:

http://www.stlsolo.org/Portals/57ad7180-c5e7-49f5-b282-c6475cdb7ee7/Roll Bars and Harnesses.pdf

I checked during my test drive how much clearance I had, and it will get fairly close for me (6" tall). I seemed to have about 2" of (imaginary) head room without helmet.

For track days, I don't have personal experience. But from what I hear, different organizations have different rules for open cars. Some of them go as far as not allowing open cars at all. So if you know who organizes the track days that you want to attend, you might want to check with them ahead of time.
 

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I tracked my car 3 weeks ago with the Panoz guys at Road Atlanta. No Hardtop was required. I ran all day with the top off. I don't have the hardtop so I can't add to your wind noise question but I would bet that the car is louder inside with the top on. I mean louder as in more engine noise, not wind noise.
 

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The answer is: It depends on the organizing body, check before you register. Some I have been to require a hardtop, some require any kind of top (so a soft top can be used). Some don't care.
 

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I've now run three different organizer's autocrosses, no tops required with any of them. Each though is affiliated in some way with the SCCA.

I put my hardtop on tonight or tomorrow, so I'll report back on the noise differential.
 

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First run with the hard top on. The wind noise is significantly lower (almost non-existent). Unfortunately, the engine/QS exhaust note and vibration appear to be even louder :rolleyes:

I like it but the missus will grow tired of it quickly.
 

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I think the QS helps make the interior louder with the HT on. I actually doesn't sound louder to me on the outside. I was happy to find my wife didn't think it was loud either :cool:
 

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The change in interior sound is due to what is called the "cavity effect" or "pressure pot" or "room gain" effect. In a sealed room for example, bass frequencies are reinforced when the relationship of the wavelengths of the sound are large compared to the dimensions of the enclosed space. It also will help bass sounds in the car. When you have the top off or soft top on the interior can't hold pressure. The soft top would flex for example.

If you switch back to the OE muffler the interior sound will decrease but will still be loud.

Padding won't help the matter much if at all. Extending the exhaust pipes way out may help.

The exterior sound quality won't change. The same thing happens with car stereo subwoofers and home theaters and so forth.
 

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I'm not switching it back, and I still think it sounds SWEET! So Shari will either learn to deal or we'll take her car. The hardtop sure gives it a different look. I guess I'll be doing my last autoX with it on, too. It did take me about 20 minutes to put on; i still can't believe the dealer told me it'd be better left to the dealership to put on :rolleyes: What a breeze.
 

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>>>I'm not switching it back, and I still think it sounds SWEET!<<<

I think I'll kinda like hard top driving too...cuz the exhaust and engine sound is more pronounced yet the obtrusiveness to others outside the car remains unaffected. Like a private world called Motor-Land.
 

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I really like the shape with the hardtop on and it is not that difficult to get in and out as I thought it might be.
 
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