How to: Lowering the Rear End

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MarkWade
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Re: How to: Lowering the Rear End

#16 Post by MarkWade »

Looks great! Charlie I may consider this option. Thanks for the input. The job is just begun and I am trying to get as much information up front from the well informed!

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MarkWade
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Re: How to: Lowering the Rear End

#17 Post by MarkWade »

Looks great! Charlie I may consider this option. Thanks for the input. The job is just begun and I am trying to get as much information up front from the well informed! By the way has anyone used air bags or is that a no- no?

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Greg Scallon
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Re: How to: Lowering the Rear End

#18 Post by Greg Scallon »

Laurent,
I do now know of any way to count the teeth, but I do have a document that shows exactly how many millimeters of drop you'll get for each degree you change the spring plate. If you send me an e-mail off-line, I'll be happy to send it to you.

-Greg
'58 Speedster
'56 VW Deluxe Microbus 

Mike Grant
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Re: How to: Lowering the Rear End

#19 Post by Mike Grant »

Your car looks really good with the Fuchs, Charlie. I've got a set of 15 X 5.5 and am going to put some low profile tires, and will also use these procedures to mechanically lower the car a bit. It will be cool to switch from stock to a mild outlaw look.

My wheels are on their way to Harvey Weidman to be refinished like the Fuchs on the very early 911S. The surface of the "petals" and the rim lip will be polished with a satin finish, the rest of the wheel will be a matte finish, and only a small amount of black is used around the holes.

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Mervyn Hyde
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Re: How to: Lowering the Rear End

#20 Post by Mervyn Hyde »

I would be interested in that document please Greg?

I did my left side today on the BT-6 and, with one problem, all went well. I have done the ones on my 1968 911 with the Elephant Racing bushings in the recent past and the 356 was pretty straight forward in comparison.

The bushings and torsion bars were all new, but the PO had set the 'free' spring plate angle at 16 degrees. The car was too high at the rear. I spent some getting the feel of the inner and out splines and then settled at about 13 degrees on the digital gauge. The problem was the rear axle housing would not move out of the way even with straps. The axle tube kept hitting the back of the heat exchanger but with some use of an extra lever jack and some pry bars I managed to get the spring plate out and back in. I would not want to do that too often. Am I missing something here?

RHS tomorrow ...
Merv
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John Clarke
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Re: How to: Lowering the Rear End

#21 Post by John Clarke »

Hi Guys
Vic's advice as usual is sound. Our 61 Coupe is very low at the rear. Not measured Ours but it has loads of negative camber. It looks the 'Dogs' and handles superbly, but when we carried 2 friends in the rear the trunnions in the diff started to clout !!! Be Careful.
Cheers Jay
 

Geoff Fleming
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Re: How to: Lowering the Rear End

#22 Post by Geoff Fleming »

John,
If the car handles well with the rear in its current position but 'suffers' when carrying a load, try installing one of the old style camber compensators. The old compensator did nothing for the handling but did lift the rear of the car a bit when loaded The torsion bars determine the handling while the compensator simply 'compensates' for the loss of 'lift' at the rear when driving under norma, straight aheadl conditions.
When the cars were current it was advertised that the comp. bar was the reason for the better handling of the S-90 yet this is not the case. Vic Skirmant's bar is a different device that actually does contribute toward better handling of the 356.

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Mervyn Hyde
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Re: How to: Lowering the Rear End

#23 Post by Mervyn Hyde »

Is 13-13.5 degrees still about the average recommendation for 'free' spring plate angle?

Also have others had problems with moving the axle carrier out of the way, caused by the back of the heat exchanger (LHS)?
Merv
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1963 356B T6
1968 911 SWB

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Martin Benade
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Re: How to: Lowering the Rear End

#24 Post by Martin Benade »

I don't think there is an average number as different years have different bar stiffness.
Cleveland Ohio
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Dennis ODonnell
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Re: How to: Lowering the Rear End

#25 Post by Dennis ODonnell »

"...but when we carried 2 friends in the rear..."

Double amputees?

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Mervyn Hyde
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Re: How to: Lowering the Rear End

#26 Post by Mervyn Hyde »

Thanks Martin. I have the workshop manual and that for the BT-6 with 24mm TB and no compensator says 16deg. Mine are marked by the last person to do the bushes at "17". That looks really high on the car and creates a wheel angle that seems wrong.

Most previous posts seem to suggest around 13.0degrees. I was just looking for some confirmation or other reflections on that figure.
Merv
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1963 356B T6
1968 911 SWB

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Greg Scallon
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Re: How to: Lowering the Rear End

#27 Post by Greg Scallon »

Hello Mervyn. I'll be happy to send you the angle spreadsheet I have. I just sent you an email to sort out the details.

Regarding the actual factory angle though, I don't think you really need it. I would just jack the car up, remove the wheel/hub/etc, and see where the bottom of the spring plate is at rest, relative to the floor. Then, just rotate your torsion bar until its bottom is higher by the number of inches you want to lower the car. Put it all back together and your car should be lower by that amount.

Regardless of how you do it, good luck with the project. And feel free to ping me if I can be of any further assistance.

-Greg
'58 Speedster
'56 VW Deluxe Microbus 

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Mervyn Hyde
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Re: How to: Lowering the Rear End

#28 Post by Mervyn Hyde »

Great thanks Greg. Email sent. That process is pretty much what I am doing now. It really helps having recently installed rubber bushings in there as removal of disintegrated original ones must be a pain.
Merv
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1963 356B T6
1968 911 SWB

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Mervyn Hyde
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Re: How to: Lowering the Rear End

#29 Post by Mervyn Hyde »

The spreadsheet helped Greg and both sides are now set, with the drivers side a tad higher. Sits much better now IMHO. Not a job that I would want to do on a regular basis however.
Merv
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1963 356B T6
1968 911 SWB

Geoff Fleming
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Re: How to: Lowering the Rear End

#30 Post by Geoff Fleming »

Dennis,

I have often driven with four adults aboard the 356...no amputations were necessary. Now if you want to try and put four people into, say, a Corvette, well.....

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