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The semi trailing arm suspension and it's grip ability

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Old 01-04-2017, 11:23 AM
  #31  
marc abrams
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Originally Posted by V2Rocket
Marc,
While past poor experiences can certainly cause anxiety in the future, alignment stuff has really come a long way.

Different car so apples/oranges, but I dropped my old Outback off at the Subaru dealer yesterday for a 4-wheel laser-computer-gizmo alignment.
They had it done for me in maybe an hour and $90, and gave me the print-out showing before and after figures for all 4 wheels...car feels great now.

You might be able to find a local shop (or even a dealer like I used) who is willing to throw your car up on the rack. If you can give them the alignment specs you want, and a brief overview of the 944 suspension (rear, the front is easy-peasy mac struts) they should be able to work it out for you. It's really not hard to adjust the suspension but you want the fancy equipment to actually measure the adjustments...
Your Subaru dealer sounds like a good place. The Toyota dealer where I bought my Tacoma from has a fine new car prep department. On the drive home, one center cap fell off, the other 3 were loose. Must be a New York thing that half-assed is the way of life around here. Look at me, l can't multi quote.
Old 01-04-2017, 11:34 AM
  #32  
marc abrams
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Originally Posted by harveyf
Marc, you didn't ask but years ago I mapped the camber curves for the front suspension. There's an article somewhere on my website. I remember being shocked at how minor the camber changes were during normal suspension travel. Again, there are some tricks going on in the control arm layout versus the axis of the strut that achieve some magic. Those guys were pretty sharp.
Thanks for that information. I feel better now.
Actually besides 3 bad radiator fan switch, I've had very few electrical problems.
Old 01-04-2017, 12:51 PM
  #33  
924srr27l
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Originally Posted by ddombrowski
I had planned on making my own post on this so as not to hijack this thread, but since its pretty related I'll roll with it. Anyway, the oversteer usually occurs from the apex to the track-out, as you're trying to put the power down. When I'm really pushing the car, it always feels like it has a bit of a sideslip angle, and sometimes that 'bit of an angle' gets away from you and the car goes around.

When we got the car, it had a weltmeister (thick, not sure the size) front bar on it which we took off in favor of a (going by memory here) turbo bar? I think the thinking at the time was that the front bar was not matched to the rear bar, and that we wanted the points (remember, this is chumpcar) for some other modification instead. So, we potentially can go bigger on the front bar again as Im pretty sure we still have the weltmeister bar.

Tires are 200 treadwear BFG Rivals, so not slicks, but not really street tires either. Pretty sticky though. 225/25/15.
We are running turbo front struts which have a good amount of damping to them in the front, brand new bilstein shocks in the rear.

Yes it's often difficult when a post is on the same theme but from a different member.

Cool, yes stick the thicker Roll bar on the front, the car may feel a little less unwilling to to turn in and settle (take a set) but if you can hold the apex (hopefully with no corner entry Understeer), the rear will be less likely to be coming round on you on the exit.

R

Last edited by 924srr27l; 01-05-2017 at 09:17 AM.
Old 01-04-2017, 05:35 PM
  #34  
PorscheG96
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Obviously, every suspension design has some compromises. The semi-trailing arm was chosen for simplicity and packaging. Because the design is so compact, it enhances features of the 944 like the large fuel tank and rear hatch area which owners have always enjoyed. The trade offs, of course, are the toe angles dependence on camber gain where basically the only levers to pull are arm length and mounting angle. Another cool attribute of the 944 suspension, both front and rear, is its roll center locations. They are setup for racing basically out of the box whereas later Porsche's with multilink require all new subframes, links and uprights to achieve this geometry. On the downside, there's a lot of body roll in street config due to weight up high but my stiffening the springs and / or reducing the battery, sunroof and rear hatch weight, the roll couples are brought under control and you go racing. I think its a great design.
Old 01-04-2017, 06:21 PM
  #35  
J1NX3D
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Originally Posted by marc abrams
I I just feel Porsche dropped the ball when selecting the spring and sway bar combination.
Besides the previous points made about the condition of your suspension components and your suspension geometry, what I've quoted above relating to your cars spec was the problem I had with my cars handling. Although I had no problems with grip or oversteer, when I pushed hard it had horrible handling characteristics unlike any transaxle car I'd previously owned or driven.

My '86 944 was specced exactly the same as yours- 20mm front sway bar, no rear bar. the 14mm rear bar was optional. It is the worst spec you can get for a 944. I don't know why it was the minimum spec and why both front and rear bars weren't standard spec. If I was buying a new base 944 I would want a 944 that had handled properly.

http://www.clarks-garage.com/shop-manual/susp-15.htm
refer "944 Suspension and Handling Setups"

The first thing I did was fit a 26.8mm front sway and 18mm rear sway bar- immediate improvement.
Old 01-04-2017, 06:27 PM
  #36  
V2Rocket
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^^"Any suspension will work, if it can't"
Old 01-04-2017, 06:47 PM
  #37  
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Originally Posted by marc abrams
Buying a caster/camber bubble guage and doing it in my driveway will come out far better than a UTI graduate using the latest and greatest laser light show, computerized super duper machine.
Take a look at your local PCA's approved tech inspection shops. A guarantee they've aligned 944's hundreds of times, won't beat on it because they have GT3's to beat on and you have a lowly 944, and it's not all that much more expensive than a normal shop assuming they don't do any other work on the car. As soon as they have to undo a bolt their labor rates are outrageous.

My full corner balance and alignment to specifications I provided was $500 at a PCA shop, for a cost comparison.

But I needed rear wheel bearings, and accidentally said "just do it" when they called to tell me that, so I paid a lot more than $500.
Old 01-04-2017, 06:49 PM
  #38  
924srr27l
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Originally Posted by J1NX3D
Besides the previous points made about the condition of your suspension components and your suspension geometry, what I've quoted above relating to your cars spec was the problem I had with my cars handling. Although I had no problems with grip or oversteer, when I pushed hard it had horrible handling characteristics unlike any transaxle car I'd previously owned or driven.

My '86 944 was specced exactly the same as yours- 20mm front sway bar, no rear bar. the 14mm rear bar was optional. It is the worst spec you can get for a 944. I don't know why it was the minimum spec and why both front and rear bars weren't standard spec. If I was buying a new base 944 I would want a 944 that had handled properly.

http://www.clarks-garage.com/shop-manual/susp-15.htm
refer "944 Suspension and Handling Setups"

The first thing I did was fit a 26.8mm front sway and 18mm rear sway bar- immediate improvement.

Interesting. although my (1987 924S 2.5) car originally had the 21.5mm Front ARB , but no rear ARB spec and the handling was very good with no adverse characteristics.
Having owned 5 previous 944's the 24 in comparison felt more nimble, lighter and turned in quicker. ( I think I have the quicker 924 Turbo Manual rack fitted though) I often wonder if the narrow Track, narrow 6"x15 Wheels and 195 tyres all play a part why in my opinion they handle better than an early or late 944 ?


The front motion ratio and scrub radius is as originally designed, and not the jacked out longer wishboned later 944, or the early 944 with the incorrect et23 offset.


Some of the 44's I've owned were tired and worn out and these cars were
a more loose with plenty of body roll, but others that had been looked after and fed lots of money over the years were much better, this has a part to play here as many car's drive different to others.


Hence generally why as many responses on this post, a 944 is a very good handling car in 1976 or 2017 so if some owners cars report handling issues then various things need to be checked, adjusted and replaced. Because this is not what this transaxle chassis does.


Modern car's drive very differently and are often stiffer with seemingly less roll and movement, and poor ride quality etc...and an older designed car with a different feel I believe is often seen as inferior but the biggest acid test is to "take a modern on" and you'll see how effortless and easy the Porsche transaxle's are to drive fast.......


R
Old 01-04-2017, 10:24 PM
  #39  
J1NX3D
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My previous 924 and 924T both had front and rear bars and handled very well. When I bought my 944 it didn't even occur to me to check the suspension specs, I just assumed a base model would have both bars as standard like my 24's- a competent suspension spec. It was a garage queen with 113,000km, only 60,000 km in the last 9 yrs. It got a front end service, new tyres balanced and an alignment but my first B road excursion and track day with it left me confused. It just felt wrong.

The new bars went in with all new OEM bushings and drop links and it was a night and day difference.
Old 01-05-2017, 04:06 AM
  #40  
924srr27l
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Originally Posted by J1NX3D
My previous 924 and 924T both had front and rear bars and handled very well. When I bought my 944 it didn't even occur to me to check the suspension specs, I just assumed a base model would have both bars as standard like my 24's- a competent suspension spec. It was a garage queen with 113,000km, only 60,000 km in the last 9 yrs. It got a front end service, new tyres balanced and an alignment but my first B road excursion and track day with it left me confused. It just felt wrong.

The new bars went in with all new OEM bushings and drop links and it was a night and day difference.


Is you 86 944 the later oval dash or an early car? which is often referred to as a 85.5


Wider track cars (944) transfer weight quicker than a narrower track (924) maybe this and the lack of rear ARB may of been why + the thinner front ARB


I did however use 36psi all round on the standard 924S with 21mm front and no rear ARB


The modified stiffer lighter car now runs 26psi all round (Street use)
(Michelin PS3 - 205/55/16)


R
Old 01-05-2017, 04:17 AM
  #41  
morghen
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Originally Posted by marc abrams
But the grip level seems to be less than my Daytona with a solid axle
Thats nonsense, you should know that.
Your 944 shocks are probably shot beyound any limit and when was the last time you did a 4 wheel alignment on that car?
Also, if you want it to behave like a sports car...use sports car tires on it no economy bull****.

Get premium sport tires on, new shocks and bushings, take it for a propper professional 4 wheel alignment and you will see what that car should really grip like. The difference is night and day.
Old 01-05-2017, 07:06 AM
  #42  
marc abrams
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Originally Posted by morghen
Thats nonsense, you should know that.
Your 944 shocks are probably shot beyound any limit and when was the last time you did a 4 wheel alignment on that car?
Also, if you want it to behave like a sports car...use sports car tires on it no economy bull****.

Get premium sport tires on, new shocks and bushings, take it for a propper professional 4 wheel alignment and you will see what that car should really grip like. The difference is night and day.
Wow! Now I know how Andre the Giant felt after being body slammed by Hogan!
I'm guessing that you didn't read my posts, number 8 and 21
Old 01-05-2017, 07:57 AM
  #43  
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He was probably working on his 3rd cup of coffee!
Old 01-05-2017, 08:11 AM
  #44  
924srr27l
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Originally Posted by marc abrams
Wow! Now I know how Andre the Giant felt after being body slammed by Hogan!
I'm guessing that you didn't read my posts, number 8 and 21
He's Fiesty that one, but means well ....

R
Old 01-05-2017, 08:48 AM
  #45  
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Originally Posted by marc abrams
Wow! Now I know how Andre the Giant felt after being body slammed by Hogan!
I'm guessing that you didn't read my posts, number 8 and 21
Lol...now you are showing your age.


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