[mdss]

Hi

sorry the first post i make is to ask for help



My car has undergone a major overhaul with new wishbones anti roll ball bushes and basically everthing on the front send being replaced. I even had a a new set of koni mo30 adjustable shocks fitted.



The car feels fantastic at below 60mph rock solid steering feel just as a 968 should.



When i drive at higher speeds the steering becomes light and vague and almost boat like, the car was like this before the front end overhaul was done and is exactly the same after.

I noticed that the standard front splitter(lower bumper section) was missing but both undertrays(metal and platic) were present, my question is this could the lack of the front splitter be causing lift and making the steering feel light and "boaty."

(i have ordered a new geniune splitter that connects to the undertray)

I know with most car the lack of splitter would make little difference but on cars as over developed as these i thought i may make a difference.



Also i heard our power steering becomes heavier at higher speed i.e. assisting less as this is not the case on my car do you think i may have a fault related to the power steering pump etc, and what do you guys think to me taking the pas belt off and driving the car if the steering feels ok with the belt off would i be right in thinnking i have a fault on the pas side.



Sorry for the rant i have done a search for similar posts and although there were a few there seemd to be no definitive answers, if i am mistaken please accept my apologies



Thanks in advance for any help.

oh yes forgot to say had all the alignment done etc with castor etc all set to factory spec

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[ds968]

I have no splitter and I have driven the car at 160-170 mph ( SPEEDO READING ), so probably at 155-160 mph real speed,

on several occasions and the steering feels as solid as it does at lower speeds. I would look elsewhere for the cause

IMO, the lack of a splitter is likely not the problem..

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[White968]

I got my car up to 143mph and my steering was great. My car felt well planted at those speeds.

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[mdss]

Thanks guys i think it must be a problem on the pas side then, i may disconnect the belt and see how it feels.



Once again thanks.

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[flash]

each car responds a bit differently to alignment specs - you may find that you need to fiddle with the settings to get the feel you want



tire pressure can play into this too, as can tire compound



did they set the ride height when they did the alignment?



did they set the rear toe angle?

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[ds968]

somewhere on this forum there is at least one thread that discusses the possible solutions to the loose steering feel as well as pros and cons of modifying the system even though as i mentioned before that my steering feels the same at high speeds as it does at lower speeds, i don't particularly like all of the power assistance these cars have because of that light feel to the steering. but i recall reading and talking to a few folks here that the changes necessary are too much of a hassle , so i left it alone

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[flash]

as i was saying, it differs from one car to the next - for example, i have the white car aligned to nearly stock, and the steering on that one is heavier than it is on my blue car with monster tires and aggressive alignment



toe and castor are critical on these cars, and dramatically affect the way it feels - very small changes make very big differences

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[mdss]

Hi



thanks for the replys great forum, i am in the uk so right hand drive and we drive on the left what setting do you recommend? i made an error the car is fitted with koni sport shocks not m030 so not height adjustable but the height was measured and it was fine.



What toe and castor settings do you think especially rear toe. The tyres are good they are pirelli p zero.

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[flash]

rear height is still adjustable via the eccentrics - the car should sit level



for an array of different alignment specs, see the "Alignment Specs" thread



make sure the inflation is correct - somewhere around 36psi all around

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[mdss]

Thanks for the prompt reply i when you say eccentrics are you referring to the torsion bar?

The tyres are inflated to near 36 psi i have plaayed around with the pressures to no avail.



thanks again i will view the thread you recommended.

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[flash]

the eccentrics are on the rear sheet metal trailing arms

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[mdss]

i have searched eccntrics and cannot find a post on how to adjust them please could you guide me to a "how to" for eccentrics, also where should i measure the height of the front and rear from? thanks again your a legend.

sorry i meant eccentrics not eccntrics i spelt it correctly honest <img src="/forum/images/smilies/968/ohmy.gif" class="smilie" alt="" />

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[flash]

that one is fairly well described including pictures in the workshop manual on page 44-7



while the book has a different method, and is much more difficult though more accurate, for street car purposes, you can measure from the center of the wheel to the top of the wheel arch, or from the ground to the top of the arch



do this just as you would do an alignment, with the car loaded as normally driven, including the appropriate weight of the driver, and 1/2 tank of fuel

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[mdss]

where can i get access to the workshop manual buddy?

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[mdss]

found a how to on 924.org which gives a detailed description for 923.944/968 i assume this is correct. i will check these tomorrow. the car looks equal height if the height is out i will be amazed if this could cause the vagueness but then i am usually wrong!! and i know how sensitive to settings these cars are thanks again flash you been great i will report my findings.

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[flash]

lol - looks like somebody needs to spend some time browsing the site



go to THE READING ROOM in the 968Forums Pub - there is a thread at the top with a link to a download

crap! i just tried it and it now doesn't work - i'll see what i can do about finding a new link

still looking for a free one



here's one you have to pay for:



http://www.promanuals.com/porsche-servic...s-manuals/

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[rxter]

If you guys are turning enough at 140+ to tell how tight the steering is hats off. At those speeds I am going straight or slowing down.



After I got the alignment set a bit more aggressive than stock. I think the castor is what made the real difference in steering feel - it kind of wanders and feels very light when going straight. But in the twisties it is perfect. Like Bob said a small change can make a big difference in the way it feels.

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[Eric_Oz_S2]

[quote name='mdss' timestamp='1311628741' post='113164']

where can i get access to the workshop manual buddy?

[/quote]

They're all here:



http://www.cannell.co.uk/Manuals.htm



Check the caster adjustment tabs on the back of the A arms. They should generally be in the down to outwards positions. More caster (tabs fully out) will give the most caster. You should also check the camber and toe in. If you have toe out your steering will be vague. This can also be compounded more by different tyres types. I have found some tyres have a much greater tendency to "wander". I had some Falkens that were terrible in this regard.

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[flash]

cool - that link wasn't working yesterday - that's the one i had on the thread in the library

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[tamathumper]

I was wondering where I'd gotten my copy... that was it.

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