I need to do something with the front end of my 412 this summer to cure the wobble.
I have found a pair of replacement strut tops with the asymetrical bolt pattern and have a spare set of 412 struts so have some of the parts already and can do this part of the mods pretty easily (hopefully) but the actual mod for the struts to use a different insert has me confused.
I have read references to two different methods described by Ray and am favouring the idea of putting the Golf strut tubes inside of the 412 struts and having them welded in. Is this method safer than having the extensions machined? It certainly seems to be the more straightforward approach?
With either of these methods is it better to use the 412 stock spring or another one, I'm sure I read somewhere about a BMW spring but can't find it now?
I'm interested to see what other people have done and how well the mods have lasted and how well they drive?
Which is the best modification to the front struts?
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wshawn
- Posts: 209
- Joined: Thu Dec 27, 2007 6:36 am
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ubercrap
- Posts: 1394
- Joined: Sun Apr 18, 2004 8:00 pm
I found the Golf strut tubes are too large to fit easily. Measure some first before you try. Maybe Rabbit?
Edit: Forgot you were in England, the Golf II struts were the ones I tried- Rabbit=Golf I of course.
Edit: Forgot you were in England, the Golf II struts were the ones I tried- Rabbit=Golf I of course.
Last edited by ubercrap on Thu Jul 10, 2008 2:12 pm, edited 1 time in total.
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raygreenwood
- Posts: 11907
- Joined: Wed Jan 22, 2003 12:01 am
The thing is this....unless you really want to do work (others may beg to differ but I've worked with far too many 411/412)....the BMW springs will net you nothing that proper mods with a stock springs won't get you.
The Type 4 stocksprings are waaaaay oversized. In compressed state they are many more than a match for this cars weight in most any environment. That being said...you can't just go cutting them. They are progressive in nature and temper. You can take up to 1/2 coil off without adverse issue. Or even better, you can compress them about 1.5"max ...but while doing so you must shorten the strut rod and lower the bushing.
The problem is this. If you use a shortened...but stifffer spring and it lowers the suspension....the strut will not be fully extended. That also means that you will not be using a gas strut....because that will automaticlaly fully extend the strut rod and unseat the spring.
The best way I have found....and the valving on these strut cartridges has been verified. I have several years on this set-up. Its about 200% better than stock and is similar in ratio to stock so you don't get issues in either compression or rebound.
These are the audi 4000/ vw quantum KYB GR-2 low pressure gas strut inserts with an adaptor stub machined at the top.
Mine....has the stub machined to compress the front spring for slightly more tension...just under 1". It also lowers the front end dead level with the rear. In the process...what many do not understand.....is that every mm you lower the front (to a certain point) raises the rear valance and pivots the body around the rear axle.
So this intense issue people get looking at the 411/412 and "feeling" like they MUST lower it two inches....is a bit defective....or deceptive.
You lower the front by anyamount...and the rear rises. One inch down in front brings the back up by 3/8" to 1/2".
Be careful here. This is where it gets confusing. The problem is the 411/412 is angled up...forward. look at he rocker panels under the doors. One primary concern is to get that panel at least...parrallel to the ground if not tilted forward.
By lowering the front....the rear end of the rocker panel does not actually "lift"..it pivots. So.....it does not take much actual lowering in the front to straighten the car. That also means that it takes not much more in the front to actually lower the car and not just straighten it.
In the past...I have said do not go more than about 1" in the front. It compresses the spring enough to make the front end damaging to its own ball joints unless you go back to an oil strut.....and then whats the point at all. You can however....cut off 1 coil on top (not bottom) that gives anywhere from .5" to 3/4" depedning on which spribng. Then compress you 1". You have lowered 2". Because its now tilted teh rocker panel forward out of parralell with the ground...its greatly apparent now.
Actually with 205/60-15's and 1" lowering in the front...it gives the overall appearance and ride control of a lowering of about 2"to 2.25". This is especially so with the audi strut cartridge.
But, I did not have to cut my springs at all to compress 1". If you compress more
The symmetrical bushings are junk. I would not use them on anything. Brand new old stock ones (because ofage) are defective. I have found dozens of them with the age cracks that happen from sitting on the shelf. You cannot see these until you install them.
That being said, installing the assymetrcial ones takes drilling several new holes...and grinding the center area out some.
Or...you can do the wierd thing I did. I cut out the center sections of the flange plate for symmetrical bushings and welded in the center section of the asymmetrical one. Then just ground the center section and bolted it on. So I have a symmetrical bushing plate with an symettrical bushing inside.
I can e-mail you the stub deign to bolt the audi strut cartridge up. I also have numerous other mods that really help to make the struts perform better I can e-mail as well.
the reason why to contemplate this...is because neither tehearly or late strut cartridges are available. Everything on the shelf was manufactured no later than 1991. It shot or marginal in seal condition and there will be no more. I would make the mods to something replaceable. Ray
The Type 4 stocksprings are waaaaay oversized. In compressed state they are many more than a match for this cars weight in most any environment. That being said...you can't just go cutting them. They are progressive in nature and temper. You can take up to 1/2 coil off without adverse issue. Or even better, you can compress them about 1.5"max ...but while doing so you must shorten the strut rod and lower the bushing.
The problem is this. If you use a shortened...but stifffer spring and it lowers the suspension....the strut will not be fully extended. That also means that you will not be using a gas strut....because that will automaticlaly fully extend the strut rod and unseat the spring.
The best way I have found....and the valving on these strut cartridges has been verified. I have several years on this set-up. Its about 200% better than stock and is similar in ratio to stock so you don't get issues in either compression or rebound.
These are the audi 4000/ vw quantum KYB GR-2 low pressure gas strut inserts with an adaptor stub machined at the top.
Mine....has the stub machined to compress the front spring for slightly more tension...just under 1". It also lowers the front end dead level with the rear. In the process...what many do not understand.....is that every mm you lower the front (to a certain point) raises the rear valance and pivots the body around the rear axle.
So this intense issue people get looking at the 411/412 and "feeling" like they MUST lower it two inches....is a bit defective....or deceptive.
You lower the front by anyamount...and the rear rises. One inch down in front brings the back up by 3/8" to 1/2".
Be careful here. This is where it gets confusing. The problem is the 411/412 is angled up...forward. look at he rocker panels under the doors. One primary concern is to get that panel at least...parrallel to the ground if not tilted forward.
By lowering the front....the rear end of the rocker panel does not actually "lift"..it pivots. So.....it does not take much actual lowering in the front to straighten the car. That also means that it takes not much more in the front to actually lower the car and not just straighten it.
In the past...I have said do not go more than about 1" in the front. It compresses the spring enough to make the front end damaging to its own ball joints unless you go back to an oil strut.....and then whats the point at all. You can however....cut off 1 coil on top (not bottom) that gives anywhere from .5" to 3/4" depedning on which spribng. Then compress you 1". You have lowered 2". Because its now tilted teh rocker panel forward out of parralell with the ground...its greatly apparent now.
Actually with 205/60-15's and 1" lowering in the front...it gives the overall appearance and ride control of a lowering of about 2"to 2.25". This is especially so with the audi strut cartridge.
But, I did not have to cut my springs at all to compress 1". If you compress more
The symmetrical bushings are junk. I would not use them on anything. Brand new old stock ones (because ofage) are defective. I have found dozens of them with the age cracks that happen from sitting on the shelf. You cannot see these until you install them.
That being said, installing the assymetrcial ones takes drilling several new holes...and grinding the center area out some.
Or...you can do the wierd thing I did. I cut out the center sections of the flange plate for symmetrical bushings and welded in the center section of the asymmetrical one. Then just ground the center section and bolted it on. So I have a symmetrical bushing plate with an symettrical bushing inside.
I can e-mail you the stub deign to bolt the audi strut cartridge up. I also have numerous other mods that really help to make the struts perform better I can e-mail as well.
the reason why to contemplate this...is because neither tehearly or late strut cartridges are available. Everything on the shelf was manufactured no later than 1991. It shot or marginal in seal condition and there will be no more. I would make the mods to something replaceable. Ray
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wshawn
- Posts: 209
- Joined: Thu Dec 27, 2007 6:36 am
So in a nutshell Ray the stub fitted to the top of the Audi strut is better than the Golf/Rabbit strut welded into the 412 strut?
If so, do you have a part number for the Audi strut inserts as here in the UK many of the dealers call the cars by a different name and you get looked at as if you are stupid asking for parts for a car for a foreign market.
Unlike many I'm not fussed about the lowering of the front end on my 412, all I want from it is to be a usable and safe daily runner. Therefore it sounds like the stock spring is the way to go, preferably uncut.
If so, do you have a part number for the Audi strut inserts as here in the UK many of the dealers call the cars by a different name and you get looked at as if you are stupid asking for parts for a car for a foreign market.
Unlike many I'm not fussed about the lowering of the front end on my 412, all I want from it is to be a usable and safe daily runner. Therefore it sounds like the stock spring is the way to go, preferably uncut.
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raygreenwood
- Posts: 11907
- Joined: Wed Jan 22, 2003 12:01 am
The slip-in, weld in method was only to do two things. (1) it allowed a way to cut the top of the 411/412 strut tube down a little without having to move the lower perch or rethread the top. In this way...one could have several inches of lowering ability without sacrificing the integrity of the spring perch and the lower ball joint mounting.
The problem is that the strut rod of the audi/vw cartridge is some 3-4" too short. You still have to have the stub either way.
Bear in mind...that if you wanted more than the almost one inch I lowered the front of mine...you can have the stub made shorter up to maybe 2" lower before geetting into strength issues.
Also bear in mind....that as you shorten the strut rod...the distance between the upper and lower spring perch decreases. That means the spring becomes much more compressed...meaning much stiffer and less progressive. It can become damaging to both spring and suspension if you go more than an inch or two.
I don't think anyone yet...even those racing have done exactly as I recommended...completely. I know for a fact that the mod as I have it with teh stub, the lowering, low profile tires..and most especially the valving, extra strut cartridge stiffness and slightly compressed main spring...is plenty stiff enough even for racing...and surprisngly finely calibrated. Right now....if I jump my 195 pound self onto the font bumper...I can get more tha n3/8" to 1/2" compression of the strut. It has very controlled rebound. I go over most "sleeping policemen" at 25-30 mph without a hitch.
If you don't have access t owelding...and a sjust slightly lowered front end is fine...and greatly stiffer and still properly valved....the bolt in stub method is best. It will look stock in all respects and can be done in a coupel hours.
The most work to be done is on the strut bushing area. You have some trimming and drilling to do. The assymetrical strut bushing is worlds better than the old one...and makes a difference in handling as well. Ray
The problem is that the strut rod of the audi/vw cartridge is some 3-4" too short. You still have to have the stub either way.
Bear in mind...that if you wanted more than the almost one inch I lowered the front of mine...you can have the stub made shorter up to maybe 2" lower before geetting into strength issues.
Also bear in mind....that as you shorten the strut rod...the distance between the upper and lower spring perch decreases. That means the spring becomes much more compressed...meaning much stiffer and less progressive. It can become damaging to both spring and suspension if you go more than an inch or two.
I don't think anyone yet...even those racing have done exactly as I recommended...completely. I know for a fact that the mod as I have it with teh stub, the lowering, low profile tires..and most especially the valving, extra strut cartridge stiffness and slightly compressed main spring...is plenty stiff enough even for racing...and surprisngly finely calibrated. Right now....if I jump my 195 pound self onto the font bumper...I can get more tha n3/8" to 1/2" compression of the strut. It has very controlled rebound. I go over most "sleeping policemen" at 25-30 mph without a hitch.
If you don't have access t owelding...and a sjust slightly lowered front end is fine...and greatly stiffer and still properly valved....the bolt in stub method is best. It will look stock in all respects and can be done in a coupel hours.
The most work to be done is on the strut bushing area. You have some trimming and drilling to do. The assymetrical strut bushing is worlds better than the old one...and makes a difference in handling as well. Ray
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champagne superbeetle
- Posts: 176
- Joined: Fri Oct 14, 2005 8:51 am
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raygreenwood
- Posts: 11907
- Joined: Wed Jan 22, 2003 12:01 am
The type 4 would definatly benefit from a strut brace. In fact, there are a few for super beetel out there that could bolt right onto the type 4 with some mods....since they are using the same bolt pattern of bushing. It would also strengthen the mounting area.
The type 4 already has a swy bar that is more than enough. Especially since the front end is so lightly loaded...and this strut mod makes it so much flatter handling. The existing sway bar could definatly use upgraded urethane mounts.
The main sway to the front end that many people complain about...is not actually front end sway...its rise and dip from the rear coupled with torsional twist of the whole car. If you use a larger sway bar and stiffer shocks on the rear....along with the strut rods up front, the front sway virtually disapears. Personally I doubled the stock rear sway bar by slaving together two...and front sway is non-existent and teh whoel car handles better. Ray
The type 4 already has a swy bar that is more than enough. Especially since the front end is so lightly loaded...and this strut mod makes it so much flatter handling. The existing sway bar could definatly use upgraded urethane mounts.
The main sway to the front end that many people complain about...is not actually front end sway...its rise and dip from the rear coupled with torsional twist of the whole car. If you use a larger sway bar and stiffer shocks on the rear....along with the strut rods up front, the front sway virtually disapears. Personally I doubled the stock rear sway bar by slaving together two...and front sway is non-existent and teh whoel car handles better. Ray