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Discussion Starter · #1 ·
Does anyone else have a problem with rocks getting built up in the rear diffusser on their Quadrifoglio? I pulled out a hand full today.... Now i'm looking into installing some nice looking mud flaps to help prevent this. Haven't been able to find any aftermarket ones though. Has anyone installed any on there Quadrifoglio as of yet?

Thanks guys/gals
 

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2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
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Does anyone else have a problem with rocks getting built up in the rear diffusser on their Quadrifoglio? I pulled out a hand full today.... Now i'm looking into installing some nice looking mud flaps to help prevent this. Haven't been able to find any aftermarket ones though. Has anyone installed any on there Quadrifoglio as of yet?

Thanks guys/gals
There is a QV video posted somewhere in the forums that shows the gravel in the rear diffuser problem.
Note that the QV diffuser has scoops so that it is not clear if the rocks are tossed in by the tires or sucked in by the diffuser or some combination there of.

Unless you want to voluntarily substantially reduce your maximum speed and you want to install mudflaps, you need something that has been designed in a wind tunnel. Even on my pickup with its 75MPH max speed rated tires I have problems with the mud flaps tearing off on the road.
 

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Discussion Starter · #5 ·
My diffuser is full of rocks. Every time i wash my car, i reach in and clear them out. I'm thinking when i downgrade to a more daily user friendly tire that this will cure the problem. I'm hoping that someone makes a good set of flaps soon. My side skirts aren't chipped up yet, but getting those wrapped will be in the near future. I want someone to make a nice set of floor mats and mud flaps that will match nicely. I'm a fan of the "same brand."
 

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Does anyone else have a problem with rocks getting built up in the rear diffusser on their Quadrifoglio? I pulled out a hand full today.... Now i'm looking into installing some nice looking mud flaps to help prevent this. Haven't been able to find any aftermarket ones though. Has anyone installed any on there Quadrifoglio as of yet?

Thanks guys/gals
IF you install mud-flaps we are taking the car away from you>:) j/k....though I have not experienced this...I will say that the sticky nature of the P-Corsas makes me super happy that I clear-filmed the rear quarter, lower side skirts and wheel wells...def. kicks up a bit of gravel
 

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Discussion Starter · #7 ·
IF you install mud-flaps we are taking the car away from you>:) j/k....though I have not experienced this...I will say that the sticky nature of the P-Corsas makes me super happy that I clear-filmed the rear quarter, lower side skirts and wheel wells...def. kicks up a bit of gravel
Thinking about a lift kit with 32" wheels also. Looking for a SunKist sponsorship if you know anyone.
 

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There is a QV video posted somewhere in the forums that Note that the QV diffuser has scoops so that it is not clear if the rocks are tossed in by the tires or sucked in by the diffuser or some combination there of.
The area at the back of the wheel well is fairly well sealed, so I don't think too many rocks are getting into the diffuser that way. You could look at taping some of the small gaps between the wheel well felt and the paneling but my hunch is that's not the issue.

There are forward facing scoops that cool the differential. Some rocks can be sucked up that way.

There is also the possibility that rocks are being pulled in from the rear. The diffuser creates a huge vortex back there and small stones could get pulled into the diffuser around the exhaust pipes.
 

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mudguards are available in EU for a whole range of alfas and I am sure they will soon have them for Giulia too....i am sure they will not be designed in windtunnel but then who really cares if top speed goes from 191 to 187??:)
 

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Guys, I made diy mudflaps for my Miata. The body curves inward from the door handle line and upper wheel well arch so everything that sprays up behind the front wheels ends up on the doors and such. For a low car it's even worse.

All you need are the fender liner peg holes and two office trash cans in black. Make a pattern out of cardboard and shape it to fit at the wheel well.

On the Quad you will see actual "dive planes" or spoilers above each rear wheel well arch. They just out about an 8th inch. but are pretty short and no were close to the rockers or bumper bottom. If you could match that plastic, you'd be in good shape.
 

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The area at the back of the wheel well is fairly well sealed, so I don't think too many rocks are getting into the diffuser that way. You could look at taping some of the small gaps between the wheel well felt and the paneling but my hunch is that's not the issue.

There are forward facing scoops that cool the differential. Some rocks can be sucked up that way.

There is also the possibility that rocks are being pulled in from the rear. The diffuser creates a huge vortex back there and small stones could get pulled into the diffuser around the exhaust pipes.

The diffuser has several fairly large holes in the middle on the downward facing surface, away from the wheels. That is what I called "scoops". I don't know if rocks can get sucked in that way, but it is a possibility to consider. I believe there is also a large gap in the bottom panels in the middle of the car (to allow engine heat to escape?) that might provide another way for rocks to get in.

The diffuser is intended to direct high pressure air that is underneath the vehicle upwards at the back of the vehicle, reducing turbulence and drag. That means it is unlikely to pull in rocks from the back and more likely to pull in rocks from the front.
 
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