3.2 Lowered Before and After...is it Too Low?

[Rad Hatter]

Originally posted by turbo3six
Lowered and corner balanced since 1989, Love it!

Wow that looks familiar - about the same height as mine- original shocks?


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Wow that looks familiar - about the same height as mine- original shocks? superb thanks for sharing

Rich

[Elombard]

I cannot believe that doesnt Rub - amazing.

[turbo3six]

Yes, original shocks and still good!

[Rad Hatter]

Virtually identical height

[turbo3six]

H&R sport springs OEM shocks, corner balanced

[Rad Hatter]

Now that looks terrific !
What are your measurements?
Cheers

[lateapex911]

Originally posted by Elombard
I wonder if the susp. is too low and the geometries are screwy? ......., maybe the tuner shops have found this faster at the track? DWSD's car comes to mind. I am assuming they re-aligned after they lowered?

(Sorry if any of this sounds harsh....)

Thats the crux of it.....

What do the geometries do at those ride heights? Is the front end in a good part of the bump steer curve? Are the control arms at a high angle?

What about front roll centers in relation to rear roll centers?

What about suspension travel? Is there sufficient travel before the car hits the bump stops??

What about the springs and shocks? You say it's soft. Well, lowering a Porsche won't affect the "feel" at all, unless you change the springs and shocks, so it shouldn't "feel" any different than before, if those were left stock. If anything, the impact harsness might be higher, as the suspension has less room to move before it hits the bump stops, at which point, the suspension ceases suspending and the rubber bump stops become the suspension. Thats bad for the car. And terrible for handling, as the car will go into instant under or oversteer, depending on which end bottoms first.

Generally speaking, and of course it's impossible to tell from pictures, is when cars are lowered, springs are changed to stiffer units to control the cars movement better, as there is now less suspension travel available before the car bottoms out on the bump stops. And when you change springs to stiffer units, you need to change the shocks to stiffer ones as well, to control the higher frequency of the springs. They go hand in hand.

Honestly, lowering your car to match a picture takes none of the important issues into consideration, and is merely cosmetic, at the possible expense of suspension dynamics.

My opinion, sorry, is to find a shop that KNOWS, like TRE in the states, (as just one example) what happens to the car when lowered, and follow their recommendation. If TRE were to say that they would lower it that far, but that you should change the springs and the shocks and add a rack spacer kit, I would know that they weren't just trying to 'sell' me something, but that they were protecting me from myself!

Now, your car may be fine...I don't know your particular model well, but I do know that your method is inviting trouble.

[Elombard]

Yah you can only lower are car so much before the suspension is out of its design perameters. Then you have to start moving pickup points etc. Thats why TRE extends the lower a arms, spindles are raised etc. and why race 911s have adjustable inner mounting points for the rear bannanas. Not saying yours is too low just making sure we are all on the same page.

[Rad Hatter]

Originally posted by lateapex911
(Sorry if any of this sounds harsh....)

Thats the crux of it.....

What do the geometries do at those ride heights? Is the front end in a good part of the bump steer curve? Are the control arms at a high angle?

What about front roll centers in relation to rear roll centers?

What about suspension travel? Is there sufficient travel before the car hits the bump stops??

What about the springs and shocks? You say it's soft. Well, lowering a Porsche won't affect the "feel" at all, unless you change the springs and shocks, so it shouldn't "feel" any different than before, if those were left stock. If anything, the impact harsness might be higher, as the suspension has less room to move before it hits the bump stops, at which point, the suspension ceases suspending and the rubber bump stops become the suspension. Thats bad for the car. And terrible for handling, as the car will go into instant under or oversteer, depending on which end bottoms first.

Generally speaking, and of course it's impossible to tell from pictures, is when cars are lowered, springs are changed to stiffer units to control the cars movement better, as there is now less suspension travel available before the car bottoms out on the bump stops. And when you change springs to stiffer units, you need to change the shocks to stiffer ones as well, to control the higher frequency of the springs. They go hand in hand.

Honestly, lowering your car to match a picture takes none of the important issues into consideration, and is merely cosmetic, at the possible expense of suspension dynamics.

My opinion, sorry, is to find a shop that KNOWS, like TRE in the states, (as just one example) what happens to the car when lowered, and follow their recommendation. If TRE were to say that they would lower it that far, but that you should change the springs and the shocks and add a rack spacer kit, I would know that they weren't just trying to 'sell' me something, but that they were protecting me from myself!

Now, your car may be fine...I don't know your particular model well, but I do know that your method is inviting trouble.

Thanks very much for your reply.
Rich

[Miguel Antonett]

After all... everyone has a different set of values, IMHO you want to enjoy your car for whatever reason you have (i.e. looks, handling, performance, show-off, purist, car nuts, toy... all of the above)

This forum is GREAT!!!!!!

[imcarthur]

I am certainly no expert - rank amateur actually - but Jake makes a very good point. Do a search on the hundreds of ride height threads & after you wade through all of the fender measurement comparisons, you will find some posts & discussions from some pros.

What is the angle of your A-arm? Is it level? Does it slope towards the wheel or away from it?



This is a pic of a more or less level A-arm. My understanding is that you want level or a slope towards the wheel. When you slope the other way, you are shortening the travel of your front shock as Jake pointed out. I ran last summer with mine slammed down (slope down from wheel). Other than countless driveway issues, I thought it looked great & felt fine. But 3 times, I hit a slight pavement change at speed that felt like I had NO suspension. Not good at all. I went higher to back to level A-arms & it's fine now.

So, it IS a system & must be treated as same.

Ian

ps looks like I need a wash . . .

[Rad Hatter]

Very interesting stuff...will investigate
Cheers and thank you for the time you took to do that.
Much appreciated
Richard

[JR_NYC]

This is my SC and I can tell you on the street the ride can be punishing when you hit expansion joints or even mildly deep pot holes. And when I hit a big hole I feel like I might tear a piece of the car off. One of these days I will need to have it adjusted and possibly swap the Bilstein sport shocks for HDs.

[GaryR]

Originally posted by JR_NYC
This is my SC ...

Please take a picture in the daytime..

I think it looks PERFECT but be sure the bump steer has been set. Here is my (dirty) 964 lowered a bit with 18" Fikse's...

[GaryR]

Originally posted by lateapex911
My opinion, sorry, is to find a shop that KNOWS, like TRE in the states, (as just one example) what happens to the car when lowered, and follow their recommendation.

For SHAME! Here you are in CT with some of the best shops in the US and you reference TRE! Hairy Dog, Musante, Farnbacher Loles to name 3!!! Fo Shame!!!

[lateapex911]

You missed Jim Newtons Auto Associates! And Fairfield County Motorsports! And Deman Motorsports just over the Tappan Zee. (Rick did my motor)

I know, I know...there are dozens I could have referenced...but he's in Hong Kong...so I tried to mention a shop that's famous on this board, with a poster or two that have actually discussed roll centers and bump steer. (Tyson and Dave)

His shop may, or may not be capable of a correct set up, I just don't know, but suggesting what to ask and look for, was my goal.

[Rad Hatter]

Correct Im in HK ==the info is helpful thanks :-)

[MOMO3.2]

lateapex911/Rad Hatter:

TRE Motorsports just lowered, aligned and balanced my 1987 Carrera. First, I installed Bilstein Sports, Turbo Tie Rods, ball joints and switched my 7's to the front and added 9's to the rear. TRE also added a rack spacer. The new height is: 24, 3/4" front and 24, 1/4 rear. Based on this Rad Hatter, you should be right on.

Mike

[lateapex911]

Right...theres three keys there....the stiffer dampers to help conttrol suspension movement adn reduce bottoming, the rack spacers to help return bump steer to stock settings, and the alignment. I imagine those ride height settings are intended to provide proper roll center balance.

[GaryR]

Originally posted by MOMO3.2
TRE also added a rack spacer.
Mike

A rack spacer is the normal method to raise your steering rack to better level/align the tie rods after lowering the suspension assembly. Reality is it's done for most cars, I just did a TR6 suspension and used 3/8" spacers under the steering rack to level her all out to OEM specs.