Porsche 911 Rear Spring Plate And Torsion Bars

[@SpankysHotRodsandCustoms]

Thanks for your help and advice. Building a 911 on my channel and your tips surely help. -Spanky

[@klassikats]

Glad I could help. Kurt

[@MIKEZGAMER-g8b]

By adjusting the spring plate would i be able to lower the passenger down by half and inch or would the max be reliastically a quarter inch in ride height drop ? My right passenger rear is 1 finger higher than all of the other corners The tires are all equal tire pressure at 32 psi

[@klassikats]

The answer is yes, however dont rely on fender measurements. Always measure from the center of the torsion bar to the ground on a flat, hard, level surface. Kurt

[@thomaslazansky9710]

This is a really great and comprehensive instructional video. I would now feel comfortable replacing the T-bars and bushings on my 79' SC. Please keep it up and bring us more content!

[@klassikats]

Thanks Thomas, and yes we are filming almost everyday on new stuff. Kurt

[@x.x..x.x]

I agree. I now feel completely confident to do this to my 78SC

[@NN-wd2vi]

Finally a video about this «black magic»-topic. Hope to see many videos in the future. The quality and level of knowledge that you put into this work is really up with the best of the best here in YT. In my opinion at least.

[@klassikats]

Thanks for the kind words and i'm glad that you enjoyed it. Thanks for watching Kurt

[@peterandkodiak9762]

A very comprehensive video with excellent content. Very well explained by a pro mechanic! Thank you.

[@klassikats]

You are welcome!

[@GarageBiljon]

I am currently rebuilding the rear suspension of my 924 and your video has really helped me to understand the reindexing of the torsion bars.

[@klassikats]

Great glad that it helped, Thanks for watching Kurt

[@MrJearley6]

Thank you so much for this video!!! I know this is two years old I learn so much from you !!! Thank you!!

[@klassikats]

Glad it was helpful! Kurt

[@3.2Carrera]

Thanks for this one as well Kurt. I did this! My car is an '89 so the torsion bar hole in the bodywork has that notch on the bottom so I could take the entire assembly out as one piece and then use a mallet to separate the spring plate and bar. Everything went back together just as you said and I got to see exactly the effect on the inner and outer torsion bar splines to the spring plate angle. These engineers thought of everything. These cars are amazing and I love how things like this are achievable. I've already been studying your alignment video and I thanked you in advance there as well. A side benefit after doing this is to turn the eccentrics for the rear toe and camber for fun to get familiar with what they do to the rear wheel alignment before tackling that project. Thanks again.

[@klassikats]

You are welcome glad to be of help to you Kurt

[@johnfreeman1189]

Such valuable information. Thanks for your expertise and also have to give credit to the person behind the camera. Great work!

[@klassikats]

Our pleasure!

[@Petrolhead912]

Maybe this will help someone going forward, just today October 24 ive done the same job. I found that the end cap at the outer end of the spring plate (spline end ) can be knocked out once the plates are off the car , the new caps can be purchased from Buttys Bits in the uk. Removal of the cap allows better access to the splines for cleaning greasing etc , plus you can also mark the position on the end of the torsion bar and corresponding position on the spring plate cover , this makes it easier to see how many splines you move on the outer. Thanks again kurt

[@klassikats]

Yes the end caps can be easily punched out. But there is no need to buy new ones as they are a simple concave washer that is easily re-installed and lightly seated with a hammer. Kurt

[@topdeckdog]

Amazing. I can't afford a 911 but still dream that I will be able to one day. I don't doubt that everything you're teaching will help me make a smarter purchase if that day ever comes. 👍

[@klassikats]

Glad to help and I hope that one day your able to own one of these cars. Kurt

[@x.x..x.x]

This was such a wonderful video. Thank you for doing this for the Porsche community.

[@klassikats]

Glad you enjoyed it!

[@r.m.2450]

As someone just getting to learn more about the ins and outs of these cars, I really appreciate how you laid out the video. Gives me confidence to start tackling work on my car. Was wondering if you could share your experience and any opinions you had regarding switching over from torsion bars to coil spring set ups in the rear for these G body cars. On the surface, it seems like adjusting ride height and spring rates would be a lot less time consuming/involved with coils.

[@klassikats]

RM, So there are pros and cons to each system. The torsion bar system is compact, infinitely adjustable, and does not add to the vehicles un-sprung weight. They also extend the basis of support further along the vehicle making it more stable on the road. The downside is that they can be more time consuming to adjust, at least in the rear of the vehicle. A strut, (coil over spring assembly) can be easier to adjust spring preload however, it comes with a number of draw backs. The Strut assembly adds more un-sprung weight to the wheel than a torsion bar system does, When retrofitting the system to a 911 it will shorten up the basis of support, and lastly the shock mounts on a 911 are not designed to carry the weight of the vehicle therefore you will need to re-enforce those areas to do so. There is one advantage to a coil spring system in that you can use a variable rate spring. Meaning that as the spring moves through its range of motion spring pressure can change. One last point, whether adjusting a coil spring or torsion bar you are changing preload not spring rate. Spring rate is designed into the spring and cannot be changed in the field. Hope that helps Kurt

[@wilsonng911]

Great explanation and video👍👍

[@klassikats]

Glad you liked it! Kurt

[@thomas2857]

Great video! As always from you! I would appreciate a video to see how you proceed to raise a 911 G body car in front and rear ride height without dismanteling the axles. Because most of 911s are way too low adjusted...This results in a poor driving comfort. Especially how you verify and adjust the wheel loads and the alignment in a pragmatic way for DIY...and how do you setup a perfect 911 for ambitioned dring on public roads? Stiffer torsion bars, thicker anti roll bars? Or do you prefer stiffer suspension?

[@klassikats]

Thomas, This is a subject we have been talking about doing a video on here in the shop. There are so many opinions about what is right and what is not right when it comes to suspension set up. When it comes to adjusting ride height and depending how much adjustment is required it often cannot be done without complete dis-assemble of the rear trailing arms. Even when using the adjustable swing arms. When it comes to my favorite set up on a 911 I use a 26 mm rear bar set with a 19 mm front bar set, and stock rubber suspension bushings, ride height at the Euro Spec. I never recommend using bronze of poly urethane bushings for street driven vehicles and tire selection and alignment values will also play a big part in how the car handles on the street. Thanks for watching an thanks for letting me know what you would like to see. Kurt

[@Glenvw911]

great video, so much detail. Thank you.

[@klassikats]

Glad you enjoyed it! and thanks for watching Kurt

[@davidnaaraat7052]

Excellent video, big help!

[@klassikats]

Glad you liked it. Thanks for watching

[@jaherrera72]

Great video, thank you!!

[@klassikats]

My pleasure!

[@mrtoronto3512]

If I can ask a question, right at the 21:00min mark you can see corrosion around the hole. How long can you let it go before you need to send to the body shop as you mentioned earlier in the video? Can you put POR15 on that to help? Thank you for your videos.

[@klassikats]

As long as the body is still structurally sound, you can clean up the area and repaint it. I don't know if I would use POR15 as it is a fairly thick product and it might interfere with installing the new bushing. Kurt

[@mrtoronto3512]

@@klassikats Thank you for the reply Kurt

[@bryceg5709]

I made a tool on my 3d printer it goes on the outer splines and is marked with the inner spline 9 degree angles and has a ring you turn. pop it on index the ring to be say 5 9 degree marks counterclockwise of 12 o'clock pull bar out aim indicator at 12 oclock and insert. bang 12 O clock. now you use your magnetic angle tool and since it will only go on at 8.18 degree increments its very easy to hit the spline you want. Now I can directly hit a degree angle pretty much first shot. atleast once I have first trial fit angle.

[@klassikats]

Nice. Kurt

[@anesennaidoo5279]

Such an excellent video / tutorial. Thank you

[@klassikats]

Glad it was helpful! Kurt

[@PA28pilot]

Fantastic video..thanks so much. Really helped me !

[@klassikats]

Glad to of helped. Kurt

[@abdulrazaqali9249]

Another great video, thank you 🙏🏼

[@klassikats]

Thanks, Glad you enjoyed it! Kurt

[@rickmcg5355]

Wow, great video!

[@klassikats]

Glad you enjoyed it Kurt

[@David_Inc]

Good information but definitely counter to OEM bushing install which is done dry with bonded bushings. How do you find this differs in end result?

[@klassikats]

David, As i said in the video Porsche does not offer the bushing separately and therefore you would have to replace the entire swing arm assembly. Even when replacing the entire arm I have also always used silicone grease on the outside of the bushings to help with installation. Installing using silicone grease was also recommended by the factory instructors when i attended the Porsche suspension school. I have installed 100's of these swing bushings now and have always had good results just so long as you match the bushing hardness to the factory setting. I have a couple of customers cars out there that are true daily drivers that have changed bushings on over 15 years ago and are still wearing well and functioning as they should. Thanks for watching Kurt

[@David_Inc]

@@klassikats do the bushings eventually need to be regreased with this method or does it wash out in time with no effect?

[@klassikats]

@@David_Inc David, The bushings do not need to be re-greased. The silicone grease is only there to aid with installation. Yes, the grease will wear out of the bushing fairly quickly with normal use and with no change in performance.

[@scottyjue3125]

Thank You for a Very Informative Video on Changing Out and Setting the Larger Diameter Rear Torsion Bars to the Spring Plates. In the Video at About 26:44 Minutes, You Pulled the Torsion Bar Out From the Tube, and Adjusted About 5 Splines. Why Can't the Adjustment Be Made on the Outside Spline Going Into the Spring Plate Retainer? Sorry, I Don't Understand That Part. Thanks Again, Scotty

[@klassikats]

You need to to move the torsions bars on both splines to make a small degree change. If you just make a one spline change on either the inner or outer splines it will raise or lower the vehicle substantially. Kurt

[@scottyjue3125]

Thank Youfor the Reply Kurt, I Will Review the Ratios You Give on the Video Again.

[@scottyjue3125]

@@klassikats We Finally Did the Torsion Bar Swap Using Aftermarket Adjustable Spring Plates, and Poly Bronze Bushings. We Did Have to Adjust the the Inner and Outer Splines as You did In the Video. Do the Torsion Bars Shift In the Torsion Tube While Your Driving the Car? Thanks Again Kurt

[@klassikats]

No once the bars are installed they will stay where they are at. Not a big fan of the poly bronze bushings. They are way to stiff, will wear the chassis hole and tend to be noisy and will require constant greasing. Kurt

[@nevenmacewan1869]

Do you have any preference as to a supplier of the rubber bushings? Stoddart? Elephant Racing? thanks

[@klassikats]

The Bushings we use are the URO brand, "Heavy Duty" with a Shore "A" rating of between 80 - 85. These are the ones that closely match the original Porsche Rubber durometer ratings. You can buy these at several different suppliers like Partsklassik, Pelican Parts, or ECS-Tuning. Kurt

[@FredBTs]

Probably a stupid question BUT if I zero my level inside the door why does the car need to perfectly level?

[@klassikats]

Fred, You can absolutely do that, just don't forget to re-zero when going from side to side. For it removes a possible failure point. It also makes it faster for me when checking side-to-side angles.

[@peterfrode2378]

Good video as usual. I have the same torsion bars. How much would you say you change the ride height in the fine adjustment for each 1 degree or 0.1 degree what ever is the more common way to tell?

[@klassikats]

The smallest change you can make is about .82 of a degree. One spline forward and one spline back. Depending on the bar size you are using this can be between 5 to 10 mm in ride height change. Kurt

[@peterfrode2378]

@@klassikats thanks. I have 26mm torsion bars and want do do the last bit with the fine adjustment on the spring plate. I need the car to go 1/4 inch higher.

[@peterfrode2378]

I went with the about 0.8 degrees and it gave me the 1/4 inch in ride height I needed. Thanks for the advice

[@twistedwired]

Beautiful!

[@klassikats]

Thank you!

[@roeljanssen1982]

Hi Kurt, yesterday I found some 28mm (white) Sway-a-way bars on my 1977 911 coupe. Hoping you could give me some advise what inclination to use. I hope these are any good for regular road use… or is it wise to switch to stock bars?😅

[@klassikats]

Roel, Sorry for my late reply, 28 mm bars in a 1977 are going to be way to stiff. The biggest bar I would use is a 26 mm for that car. Stock on that car would have been 23-24 mm depending on what it was optioned with. If you are going to try and set a them up I would start with a spring plate setting a around 22 - 24 degrees and see what it looks like. Kurt

[@roeljanssen1982]

@@klassikats Thanks Kurt! I’ll give it a go with these bars… if it turns out my back can’t handle these, I guess 26 is the way to go. Will let you know, but first have to finish the project 😅

[@mrjohnirons]

Great video . What is your preferred bushing to use as the replacement? There are so many on the market but I'm not sure sure what brand/durometer to choose - URO, Elephant, Rennline etc. Also, if the original spring plates look to be in good shape, is it worth replacing the whole assembly or is that overkill just to have them look pretty? Mine is a '76 911 btw.

[@klassikats]

I use the URO brand heavy duty ones. Here is a link to them, amzn.to/3P1FCwx They are closest to the factory bushings that we have tested. Kurt

[@mrjohnirons]

@@klassikats Thank you Kurt!

[@user-gl2eq2ly4g]

Excellent

[@klassikats]

Thank you so much 😀

[@RichieRich845]

👍

[@klassikats]

Thanks