How-to: B7 Avant auto boot opening

[JMGR33N]

Hey all, I've been looking at knocking up something to do auto boot opening on my Avant for a little while. Finally got it to work how I want.

So here's what I did...

Firstly ordered a pair of new gas struts. I got the 2005 A6 Avant ones. They are the same length as the B7 ones I had but higher pressure. (£13 eBay)

Old

New

I also ordered a pair of engineering compression springs, 38mm long x 16mm diameter. (£2 eBay) **See Note at bottom**
And
Pack of 4 washers 8.5mm internal diameter x 16mm external diameter. (£1 eBay)

I also bought 30cm of black shrink wrap. (£1 eBay)

Next unscrew the ends off of the new struts

Slide on one washer

Slide on one spring

Slide on the second washer

Screw the end back on the strut

Cut a piece of shrink wrap long enough to cover the spring and washers with a few mm excess at either end.

Hold the wrap in place and shrink it down with heat. I used a mini blow torch.

Do the same to both new struts and then replace the old ones on your car with these.

**NOTE: after first fit I found the springs were too long so I measured up and found that they only needed to be approx 18mm long. So I cut one spring in half and ground the cut end flat**

Here's the finished article:

 

[ajax1976]

This is great, love wee home brew things like this!!

Top work

 

[DrStrange]

Damn! Thats a nice auto boot lid open. Love how professional the heat shrink looks. Top Job

 

[SDHA4SLine]

Brilliant, great mod well done sir. I shall be copying you very soon .

Now if you could just figure out mod to auto close ...

 

[alpesh26]

Nice work!! Would this work on a saloon?

 

[JMGR33N]

Nice work!! Would this work on a saloon?

No idea mate, deff not with these particular parts.

I believe there are proper sprung oem hinges you can use on the saloon. Think there was another thread on here talking about.

 

[sabaxter]

Brilliant write up and video

 

[gary_a4_quattro]

Great modification , clear and concise details too ! Top job !

 

[Wahlstrom]

Will it do on a B6 ?

 

[JMGR33N]

In all honesty I couldn't say for sure. In principle it should work. But I don't know if the B6 struts are the same length, what pressure they are and what size spring would be needed.
You need to do some carful trial and error.

 

[DrEvil]

Might be a daft question, but is it harder to close the boot?

 

[JMGR33N]

No not daft at all.

the answer is yes, it did make it fractionally harder to pull the lid down. due to the extra pressure in the struts, but the springs only compress on the last few inches of closure so have the whole lids weight in them. so have not found it any different getting it to latch shut.

 

[DrEvil]

Cheers for the answer.

I was just wondering if I was to do this, if the missus would end up moaning at me because she would have trouble closing the boot!

Another question, if you open it by hand, is quite a forceable open (it looks fairly controled from the video)

Good cheap mod, and easily reversible so am tempted to look into it!

 

[JMGR33N]

Opening by hand there s not a lot of difference, there is not a lot of force in the initial pop.

To be honest you could probably use struts with less pressure than i have. I just didn't want to spend a fortune buying all different pressure struts to test them so i went pretty high. 105nm more than standard.

It's not an oem mod so i know its not as refined as Audi could have done it, but like you say if you don't like it, for the sake of 20 odd quid its not the end of the world.

I bought a classic bug so i wouldn't fiddle with the Audi, that hasn't quite worked out... lol

 

[silviotomas]

Do you wana try this on a saloon then let me know all the sizes and stuff lol

 

[JMGR33N]

If you want to give me a saloon to keep then yea! ;-)

There's an OEM way of doing this on the saloon with proper sprung hinges. I'd go that route if i had a saloon.

 

[silviotomas]

££?

 

[jay1601]

Doing this!

Could you post a link to the bits you used

Thanks

 

[Broken Byzan]

I need this on my b5 saloon and her b5 avant. Hers needs new struts anyway Nice work.

 

[Matt James]

I might have to try this on my convertible
Cheers for the guide

 

[Broken Byzan]

I don't suppose you have the dimension of the struts to hand.? Means I don't have to buy many different ones to check spec . Unless etka has the ratings and lengths. . Hmm

 

[DrStrange]

Do you wana try this on a saloon then let me know all the sizes and stuff lol

Cant remember who now,...but 100% a member has done this to their b6 saloon. 100%!

Look in the A4 B6 section..under the heading 'Top 10 mods' or something similar.

 

[Weverall]

THIS IS INCREDIBLE

 

[B_FUR]

top job mate and great write up. I think even I could manage to do this one!!

 

[markspark]

The only problem I can see is if your sat at home with the key in your pocket with the car parked close by and you catch the button the boot would open without your knowledge

 

[JMGR33N]

It's a possibility but no different to winding down all your windows by accident, by sitting on the unlock button.

You have to hold the button solidly for a good 2-3 seconds so I'd say it'd be unlikely.

But technically yes you are correct.

 

[Weverall]

Just waiting on someon to do this for the cabriolet..

any ideas on strut length or how to find a higher rated strut the size of a cabriolet one

 

[DrStrange]

Just waiting on someon to do this for the cabriolet..

any ideas on strut length or how to find a higher rated strut the size of a cabriolet one

Me too ;-)

 

[JMGR33N]

One thing I should have mentioned. It is difficault to determine exactly what length you need to cut/buy the springs all cars a very slightly different. So what I found works really well is buy 4 extra washers. And you can use them as spacers, to fine tune the amount of "pop" you get.

 

[barkclark]

I am so doing this to my B6! I see you bought struts with a higher pressure. Any idea if it would work with lower pressured standard B6 / B7 struts?

 

[barkclark]

Also have you got a part no. for the struts you used?

 

[mrchimps]

genius! deffo doing this

 

[quiksilver_jake]

Same as Barkclark^ but debating doing it with standard pressure ones as it goes up with what looks like alot of force!
I had the same concerns about closing as people have had further up the thread.

 

[barkclark]

I think I'm probably just going to give it a go with new standard struts!

 

[quiksilver_jake]

I thought I best check mine boot unlock button works first as I've never used it, Looks like its sending a signal but not unlocking so looks like I'll have to fix that before I can carry out the MOD.

 

[DerClown]

Just waiting on someon to do this for the cabriolet..

any ideas on strut length or how to find a higher rated strut the size of a cabriolet one

Looking forward to do that !
Give you info If I be victorious
On my wifes Avant I do this mod for sure !

 

[novril]

Any chance you could link to the struts you used with removable ends? The ones I have tried dont have threaded ends!

Eager to give this a go now.

Cheers, Mark.

 

[Charlie Farley]

a great mod and i'm looking to do it myself ,but, i do have one concern to be honest that i would need to check before doing it to my avant.
Having watched the clip a fair few times i would be a little concerned on how the effect of continued shaking/clonking of the gas strut mounts when the tailgate opens and then stop abruptly at the fully open position.
under normal usage the opening of the tailgate is not subject to quite such a sudden jolt as it is under a more controlled force, the human arm/hand as it after the mod and i can see possibly problems arising around the gas strut mounts and the tailgate bracket that the strut attaches too becoming loose etc or the joints becoming problematic.
Maybe some sort of rubber buffer/damper on the strut to deflect that inital shock maybe a good addition, on motorised tailgates the rate of opening etc is controlled by a motor.
just a thought chaps to enhance a great idea and mod, and possibley save a bit of wear and tear.

 

[SootySport]

Great idea this but stand back from tailgate, wouldn't want the tailgate catching you on the chin.

 

[unitzero]

wow. this is awesome ! great idea