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Discussion Starter #1
If like me you have the TBi version of the 159, you'll no doubt be all too aware of the lack of ground clearance it has.

This was becoming a daily annoyance for me as my journey to work has a section with 4 speed ramps, the 1st of which I have to go over at <10mph to avoid scraping the underside :mad: Then later in the journey the road has a couple of uneven cambers where the bottom of the car hits the ground.

So, I had a look at the undertray and found it is positioned unnecessarily low, with room for up to 40mm extra clearance in places.

I then ordered a sheet of 1.5mm thick aluminium and set about making a replacement. Initially this was easier than expected, but then getting all the holes just right today was a bit of a pain, especially as it was freezing out there!

Haven't tested it over the usual route yet, but have raised the lowest part by around 30-40mm so grounding it should now be a thing of the past :)

The Alfa one, which is definitely a triumph of form over function has quite an unnecessarily complicated design, whereas mine is not as neat, more function over form - which I'm ok with when it's under the car!

Here's a pic of the (damaged) undertray / The aluminium after initial cutting / all finished and secured
 

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Interestly, but what is the clearance of the undertray? T
The legal maximum height of a speed hump is 10cm, and the ramp up to this height has to be ten times the height, so if the hump is outside these dimensions, then you can get them removed and ask the council to remove them as they are an 'obstructions'! :)
http://www.ukroads.org/webfiles/tal07-96.pdf
 

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Interesting!

The Tbi has that lump in the middle (the one that has the most scrapes). Did you discover what's behind it. When I bought mine I tested the Ti to make sure it cleared the speed humps. This was a Diesel. Then I tested a Lusso with Tbi. It cleared the speed humps. But I bought a Ti with Tbi engine and didn't realise this was worse.
 

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Discussion Starter #6
Interesting!

The Tbi has that lump in the middle (the one that has the most scrapes). Did you discover what's behind it. When I bought mine I tested the Ti to make sure it cleared the speed humps. This was a Diesel. Then I tested a Lusso with Tbi. It cleared the speed humps. But I bought a Ti with Tbi engine and didn't realise this was worse.
What's behind it? - the exhaust pipe - but the lowest part of the exhaust is nowhere near - I omitted this feature from mine and there is still at least 10mm clearance
 

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Discussion Starter #7
I got custom aluminuim undertray too..but it was made custom for my car...200 pounds...
looks nice - £200 is better than I expected, the aluminium sheet itself is not all that cheap ; could have saved myself a few scraped knuckles!
 

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looks nice - £200 is better than I expected, the aluminium sheet itself is not all that cheap ; could have saved myself a few scraped knuckles!
And about the same price as a new AR plastic one.
 

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Very nice job !

Not to take anything away from what you have done. Just keep an eye on the temps as you now have no additional coolinging vents. Just that when I fitted a home made sump gaurd to the Integrale I found the engine temps climbed quite a bit untill the vents were made.

But still liking youre work
 

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It actually got a second part...which is not showed in the picture...because its q4...i got second part aluminium undertray. Both are touching ...the second one was made to protect the rear operation from snow!
 

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Discussion Starter #11
Very nice job !

Not to take anything away from what you have done. Just keep an eye on the temps as you now have no additional coolinging vents. Just that when I fitted a home made sump gaurd to the Integrale I found the engine temps climbed quite a bit untill the vents were made.

But still liking youre work
The finished article does have the 4 cooling vents i just didnt have access to the camera at the time - you can just about make them out on the fitted to car pic

Have now tested over the long type speed ramps and all good so far, can go over as quick as I think is healthy for the suspension with no signs of scrapage :)
 

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My bad ! Yes you can just make them out, still loving your work.
 

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Discussion Starter #14
Great work!!!! - did you cut it yourself? what was the size of the aluminum sheet needed? Did you make any bends in it?
I got a 1.5mm thick 110x130cm sheet and had to cut a piece off one corner and secure it on the opposite corner to make it large enough. At that thickness it's pretty sturdy stuff!. For one piece 110x160cm would do it. - this was from aluminium warehouse website, was about £40 then £10 for the snippers and £15 for delivery.

Cutting the basic shape was easy after using the old tray as a template. Cutting in the vents was a bit trickier, but not all that difficult.

I made a bit of a curve near the front to get it to fit, and also increased the separation of the tray from the mounting points (/sump/exhuast) using a nuber of M16 washers.

Once I'd ordered the bits, I did wonder if it was a bad idea and if the project could turn into a nightmare, but turned out to be relatively straighforward
 

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Nice work!

Very nice Phil, got to say I'm tempted to try it myself. Whenever I have a passenger, my 2.2JTS spider scrapes on modestly uneven roads, let alone speed bumps.
Maurice
 

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Very neat job.

What's behind it? - the exhaust pipe - but the lowest part of the exhaust is nowhere near - I omitted this feature from mine and there is still at least 10mm clearance
I would imagine they made the massive bulge to stop the undertray melting. you don't need to worry with ally.
 

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Discussion Starter #18
I suppose I can just cut out this bulge and get more ground clearance!
yes - I imagine that will avoid most of of the usual scrapes

I'm planning on putting some Eibach springs on at some point so think I'll need the extra gains from doing the whole lot
 

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iv been doing a bit of research into makeing my own full car length undertray.
will imporve stability of car and should increase the MPG as well. air will be able to pass by the car alot more cleanly which creates less up pressure under the car which should making handling better.
£40 not bad for a large piece or alloy. might invest in some if i get the balls to give it a go. lol
 

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If you go that route it would be nice if the undertray could be at the lowest point at front and than go higher to the back of the car with nice diffuser in the rear bumper. That would really help with stability at higher speeds and ofcourse with lower drag and less fuel consumption.
 
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