# MK4 Rear Bags - New recommendations



## MechEngg (Jan 13, 2009)

So i blew another airlift bag this year. Seems like i am driving too low (air up maybe 1" max typically) and the top and bottom of the bag are meeting over bumps and it ends up smashing the bottom cup into the rear beam cup, digging the plastic in and cracking it. 

Recommendations for new rear bags (since i'm not going to be going airlift again or firestone 9000) would be firestone 7076's / SS5's or RE5's with either Dcups or IDF rear mounting brackets.

Any recommendations strictly based on the fact that i ride at very low heights? I was thinking firestones would be good at a low height because they are narrower (aka have to run at a higher pressure to achieve the ride height) but i'm also concerned with ride comfort and longevity.


----------



## Buck Russell (Feb 24, 2003)

IDF + SS5 without a doubt!


----------



## MechEngg (Jan 13, 2009)

Buck Russell said:


> IDF + SS5 without a doubt!


Care to elaborate? On:
- Ease of install (need to trim or bang out lower cups)
- Ride comfort at low low psi (20-30psi)
- Durability?


----------



## Buck Russell (Feb 24, 2003)

MechEngg said:


> Care to elaborate? On:
> - Ease of install (need to trim or bang out lower cups)
> - Ride comfort at low low psi (20-30psi)
> - Durability?


1. You will need to "bang out" the lower cups and clearance the pockets for the SS-5 bag. Not a major PITA, but it does need to happen.
2. Ride comfort is excellent. The double bellow bag provides excellent comfort and an aggressive spring rate.
3. Slam bags are some of the best in the industry without a doubt. I've yet to see one pop from anything but a shoddy install. 

Here are some numbers to feed your brain (I know you enjoy the facts)

Firestone 7076 rolling sleeve bag:

Port Size: 1/8" NPT
Max Diameter: 5"
Min Height: 3.95"
Max Height: 10.50"

Slam Specialties SS-5:

Port Size: 1/2"
Max Diameter: 5.5"
Min Height: 2.7"
Max Height: 8.625"


----------



## Travy (Jan 13, 2004)

I've been running the firestone/AAC setup on my car sine 2009, paired with some bilstein shocks and it rides great. http://www.airassisted.ca/u2/Firestone-Rear-Kit


----------



## MechEngg (Jan 13, 2009)

Buck Russell said:


> 1. You will need to "bang out" the lower cups and clearance the pockets for the SS-5 bag. Not a major PITA, but it does need to happen.
> 2. Ride comfort is excellent. The double bellow bag provides excellent comfort and an aggressive spring rate.
> 3. Slam bags are some of the best in the industry without a doubt. I've yet to see one pop from anything but a shoddy install.
> 
> ...


I did take a look at those numbers and once you add on the bottom bracket they are going to be very close to the same max height and compressed height, only difference being the diameter. The firestone bags are very very readily available and with the only slight difference in diameter i may give the Firestone bags a go. Less modifications and what looks like great durability. Just wish i would have decided on this sooner before i sold my firestone rear bag assembly i had in my garage last summer :laugh:



Travy said:


> I've been running the firestone/AAC setup on my car sine 2009, paired with some bilstein shocks and it rides great. http://www.airassisted.ca/u2/Firestone-Rear-Kit


Good to know. Since you have a more aggressive fitment how low do you typically drive around? (psi or height aired up) Already running bilstein shocks so it should be a good combo :thumbup:


----------



## Travy (Jan 13, 2004)

MechEngg said:


> Good to know. Since you have a more aggressive fitment how low do you typically drive around? (psi or height aired up) Already running bilstein shocks so it should be a good combo :thumbup:


I don't think I have any pics.. I'll take a look but normally I ride with the rears around 55-60psi, just a little gap so I don't burn my fenders too bad


----------



## MechEngg (Jan 13, 2009)

Travy said:


> I don't think I have any pics.. I'll take a look but normally I ride with the rears around 55-60psi, just a little gap so I don't burn my fenders too bad


Ah okay thanks for all the help. 

Too bad AAC doesn't carry them in their Canada division anymore, they only seem to be available from their US source which kills the shipping for me up here


----------



## Buck Russell (Feb 24, 2003)

Firestone sleeves aren't bad, I just don't like the ride of a non-tapered sleeve bag. Higher driving pressure, blah.


----------



## MechEngg (Jan 13, 2009)

Buck Russell said:


> Firestone sleeves aren't bad, I just don't like the ride of a non-tapered sleeve bag. Higher driving pressure, blah.


higher pressure is definitely something I'm looking to achieve with my ride height so I don't mind :thumbup: Will keep me from bottoming out all the time like my current bags do


----------



## vjg1215 (Mar 23, 2009)

I have roughly 42k miles on my AAC firestone rears and love them. Never had any other setup so i can't compare it to anything. You only have to watch out for the direction of the fitting cause it might rub with the bag. Other than that their is no modification needed.


----------



## blue bags (Jul 1, 2009)

I put right around 100k on my AAC firestone(7076) setup, drove the car every day for about 5 years before selling it and the current owner is still on them. you hear alot of stories about fitting rub holes from them, but its usually bad fitting placement or people not paying attention to them falling out of place after the car is jacked up, which i liked because you never have to worry about them being over extended. Mine did have some marks of the fitting contact point, but never failed, and at 100k+ even if they did i wouldnt have been mad with how cheap they were, I kept a spare in the trunk that i never used haha

Im sure alot of the other suggestions are just as good or maybe even better, I just never had a problem with them so i never tried anything different. they were paired with billstein rear shocks


----------



## MechEngg (Jan 13, 2009)

Ordered the firestone 7076 bag rear kit yesterday and despite only being available on the US website, AAC shipped them out from Toronto for me and even credited me for the difference in shipping. Overall wonderful service, would definitely order again and recommend if I have friends looking (I already recommend them as the best rear bag setup haha)


----------



## macleanshaun (Sep 19, 2008)

Late to the party, but I run SS5s with Koni adjustables in the rear set to 4 out of 5 on the stiff, and they are great. Ride height is 35-40 PSI on my current setup. Not bouncy. I'm in a mk6, but bags are bags, right?


----------



## euro+tuner (Feb 1, 2007)

I've had a set of Firestone 7076 bags sitting in my toolbox for the almost a year now, I just don't want to drill out the nutsert used with the Airlifts.


----------



## MechEngg (Jan 13, 2009)

euro+tuner said:


> I've had a set of Firestone 7076 bags sitting in my toolbox for the almost a year now, I just don't want to drill out the nutsert used with the Airlifts.


I am probably just going to try to knock the nutserts into the nipples and see if that works


----------



## MechEngg (Jan 13, 2009)

Rear bags came in Tuesday. Installed them tuesday evening.
Wednesday got around to installing my new brakes and bushings etc

I used to have a set of old old firestones (first gen with 1/8" inlet and no set screw) that i had never installed. The new version has 1/4" NPT port as well as a set screw you can see in the pics. Basically air the bag up, drill a smaller hole out through the threads, then air out and move the top hat to the side and use a slightly larger bit to make the hole larger. Put the upper hat back in place and screw the set screw in and it will keep your top hat in place. Great design.


----------



## harley06 (Feb 28, 2007)

those firestones get so much lift, its insane.

SS5 with Dcups here


----------



## SMG8vT (Oct 8, 2004)

vjg1215 said:


> I have roughly 42k miles on my AAC firestone rears and love them. Never had any other setup so i can't compare it to anything. You only have to watch out for the direction of the fitting cause it might rub with the bag. Other than that their is no modification needed.


Same here, had rubbing issues early-on but it's fixed now. Rides perfect.


----------



## MechEngg (Jan 13, 2009)

Goes lower than the airlift bags too. Worthy to note. Not sure if i like it or if i will put a small spacer under the bag between the bag and the billet plate


----------



## 03_uni-B (Sep 6, 2005)

Didn't know you were contemplating this, guess I missed the thread. I am running ss5's and idf's, love the ride. I had airlift tapered rears before and imo these ride way better. Buddy is running the firestones on his wagon and has no complaint, all depends on personal preference i'd say.


----------



## Buck Russell (Feb 24, 2003)

Would that be a newmatics fitting in the bag? Just curious.


----------



## MechEngg (Jan 13, 2009)

03_uni-B said:


> Didn't know you were contemplating this, guess I missed the thread. I am running ss5's and idf's, love the ride. I had airlift tapered rears before and imo these ride way better. Buddy is running the firestones on his wagon and has no complaint, all depends on personal preference i'd say.


Yup i think for me the higher psi is really what's going to do it for me. I need as much pressure as i can in the rear for dips in the road at my ride height. :thumbup:



Buck Russell said:


> Would that be a newmatics fitting in the bag? Just curious.


Yes it would. I'm not a huge fan of them but they were already fitted to the bags so i thought i'd give it a go. I have DOT compression fittings on my bench at home if these don't work out


----------



## SMG8vT (Oct 8, 2004)

Happy New Years guys!

I thought my bagged Beetle handled great until I pushed it on the track in October. Did a few laps on my HPS fronts and it felt sketchy. Already pulled the trigger on some AirLift performance fronts but I don't know what to do in the rear. I'm currently running AAC Firestones and I wouldn't mind an upgrade but there doesn't seem to be any real consensus on AAC / Firestone vs D-Cup / SS-5.

I don't mind spending the money to upgrade but no point wasting money either. Any help is much appreciated. Short clip of one of my laps because why not? https://www.youtube.com/watch?v=QUI8Hg8gAZE

TLDR: Already bought AirLift Performance fronts. Looking for recommendations on the best handling rear bags and shocks for the MK4 platform.


----------



## Buck Russell (Feb 24, 2003)

SMG8vT said:


> Happy New Years guys!
> 
> I thought my bagged Beetle handled great until I pushed it on the track in October. Did a few laps on my HPS fronts and it felt sketchy. Already pulled the trigger on some AirLift performance fronts but I don't know what to do in the rear. I'm currently running AAC Firestones and I wouldn't mind an upgrade but there doesn't seem to be any real consensus on AAC / Firestone vs D-Cup / SS-5.
> 
> ...


Thanks for the TLDR version, my life just got a whole lot easier.

IDF / SS5 combo is still where I put my money.

Rear shocks, I prefer koni over bilstein for countless reasons.


----------

