roll bar settings
- Thread starter rs phil
- Start date
Phil RS.
Sorry if this one has already been answered in the full thread, but don't have time to read the whole thread. Sorry. Looks like Paul H and others have given you lots of good advice though.
However, in my opinion you have almost answered your own question when you said what Manthey have done. The absolute biggest influence on the cars front to rear grip balance is the cars own weight. If Manthey lowered the rear and raised the front they have taken all the rake out of the car and I'm guessing that your car pretty much understeered everywhere. If so then this is definately the problem you have.
The front to rear tyre sizes sound right and it's definately not over tyred at the back.
If the rake of the car is not right in order to achieve enough front end weight (grip) then adjusting the roll bars will do absolutely nothing to cure your problem. The roll bars provide some final fine tuning. Leave your cambers and roll bars until you have the front to rear weight balance right. Call me if you want Phil i've spent several seasons racing getting these 964's and 993's to handle.
Sorry if this one has already been answered in the full thread, but don't have time to read the whole thread. Sorry. Looks like Paul H and others have given you lots of good advice though.
However, in my opinion you have almost answered your own question when you said what Manthey have done. The absolute biggest influence on the cars front to rear grip balance is the cars own weight. If Manthey lowered the rear and raised the front they have taken all the rake out of the car and I'm guessing that your car pretty much understeered everywhere. If so then this is definately the problem you have.
The front to rear tyre sizes sound right and it's definately not over tyred at the back.
If the rake of the car is not right in order to achieve enough front end weight (grip) then adjusting the roll bars will do absolutely nothing to cure your problem. The roll bars provide some final fine tuning. Leave your cambers and roll bars until you have the front to rear weight balance right. Call me if you want Phil i've spent several seasons racing getting these 964's and 993's to handle.
ORIGINAL: h_____
Care to post some vid on how it is done Melv? []
Here ya go............[
]http://www.metacafe.com/watch/319334/brutal_car_crashes_porsche_crash/
Steve Brookes
Moderator
While I am a mere novice at this game, I can see what Melv is getting at. I think this vid of young Mr Edwards in Ian's 964 cup illustrates much of what he is advising about smoother turn-in:
http://www.youtube.com/watch?v=36ue0v28KZ8&feature=related
http://www.youtube.com/watch?v=36ue0v28KZ8&feature=related
Hacki
Active member
ORIGINAL: Melv
ORIGINAL: h_____
Care to post some vid on how it is done Melv? [
Here ya go............[
http://www.metacafe.com/watch/319334/brutal_car_crashes_porsche_crash/
Is it that what you call "gentle turn in"?
my laps look better[]...i had tried some of the corners in third but was slower,if had more front grip maybe third will work
goin to take pauls (rsr) advice also and raise the rear as front tyres still werent as hot as rears at the end of the session, i appreciate any advice given as i am no walter[]
]...i had tried some of the corners in third but was slower,if had more front grip maybe third will workgoin to take pauls (rsr) advice also and raise the rear as front tyres still werent as hot as rears at the end of the session, i appreciate any advice given as i am no walter[
]paul howells
New member
Phil
I will disagree with rsr a little here,he is right in pitch of the car.But i can not see or would hope manthey did not adjust the height of the car with out no data or settings.I would like to think they set the car correct,any where between .8 to 1.5 deg at the sills depending on your preferance and car.
My comments are based on this being correct.
Corner weights are important but not the most important.
Even with porsches high tolerances,if you set all the cups and rs at the corrrect and spot on corner weights,the ride heights/pitch would vary.The stiff cars do get tired over the year,and if raced as in cup etc the chassis gets fatigued and move.Or even worse they have had some chassis damage over the years,and are then only as good as the man that put it back together.
As porsche say you can not set the car up correctly with worn bushes,uneven tire pressures,tired springs and dampers etc,it goes on and on!!
As long as the car has been set to what manthey say and the pitch is correct ,the car should be good as a starting point.
If you want more heat in the front on circuits,may be drive with abit more aggresion ,load the front more,or mechanicaly dial some more load into your tires.
But it is a road car at the end of the day.
I will disagree with rsr a little here,he is right in pitch of the car.But i can not see or would hope manthey did not adjust the height of the car with out no data or settings.I would like to think they set the car correct,any where between .8 to 1.5 deg at the sills depending on your preferance and car.
My comments are based on this being correct.
Corner weights are important but not the most important.
Even with porsches high tolerances,if you set all the cups and rs at the corrrect and spot on corner weights,the ride heights/pitch would vary.The stiff cars do get tired over the year,and if raced as in cup etc the chassis gets fatigued and move.Or even worse they have had some chassis damage over the years,and are then only as good as the man that put it back together.
As porsche say you can not set the car up correctly with worn bushes,uneven tire pressures,tired springs and dampers etc,it goes on and on!!
As long as the car has been set to what manthey say and the pitch is correct ,the car should be good as a starting point.
If you want more heat in the front on circuits,may be drive with abit more aggresion ,load the front more,or mechanicaly dial some more load into your tires.
But it is a road car at the end of the day.
thanks paul,i think i am to blame here as i said the car looked like it has less rake,which it does as before it was way too much,had a look at it last night and its maybe the extra camber on the rear giving it the much lower look at the rear
and yes you are correct its a road car.. and it doing a great job at both
and yes you are correct its a road car.. and it doing a great job at both
Paul H. I'm not saying Manthey set the car wrong. Of course they have set it within the rake range you describe of somewhere between 0.8 and 1.5 deg of rake, but I'm not sure you realise what a huge range this actual equates to. To go from one extreme of this range to the other is a change of 0.7 deg. With a wheel base of 2272mm this means a ride height change of 27.75mm at one end of the car. Just having the car anywhere within the range of 0.8 to 1.5 is a start point, but needs changing as you say to suit.
By Phil's own admission Manthey set the car up specifically for the ring. A setup for the ring will be at the lower end of the rake angle as this will settle the car more for a lot of the very high speed flowing sections. You tend to work a car very differently at the ring than on short circuits.
I spoke to Phil on the phone and he said his car was indeed fantastic at the ring, but at Mondello park, which is slow to medium speed technical circuit it understeered in every single corner. In my humble opinion he needs to change the ride heights at either end slightly (either lower the front or raise the rear) to give it more rake and slightly more weight at the front. I also had the problem Phil describes in my 993 at Brands. After a winter rebuild and setup the car understeered in every single corner. Only a 5mm change in ride height at one end (or 0.126 deg expressed as a rake angle change) the car was transformed and I was suddenly setting the fastest times I'd ever set round Brands. Before this single small change the car was understeering so much you couldn't start powering anywhere until the straight, just awful.
I'm also assuming Phil had the tyre pressures set right and all his suspension is good. I was just trying to share the info I have from experiencing the same thing Phil described, in conjunction with the fact his car was given a specific ring setup.
By Phil's own admission Manthey set the car up specifically for the ring. A setup for the ring will be at the lower end of the rake angle as this will settle the car more for a lot of the very high speed flowing sections. You tend to work a car very differently at the ring than on short circuits.
I spoke to Phil on the phone and he said his car was indeed fantastic at the ring, but at Mondello park, which is slow to medium speed technical circuit it understeered in every single corner. In my humble opinion he needs to change the ride heights at either end slightly (either lower the front or raise the rear) to give it more rake and slightly more weight at the front. I also had the problem Phil describes in my 993 at Brands. After a winter rebuild and setup the car understeered in every single corner. Only a 5mm change in ride height at one end (or 0.126 deg expressed as a rake angle change) the car was transformed and I was suddenly setting the fastest times I'd ever set round Brands. Before this single small change the car was understeering so much you couldn't start powering anywhere until the straight, just awful.
I'm also assuming Phil had the tyre pressures set right and all his suspension is good. I was just trying to share the info I have from experiencing the same thing Phil described, in conjunction with the fact his car was given a specific ring setup.
paul howells
New member
Paul M ,sorry not saying you are inferring manthey are wrong,just saying i presumed from all the feed back etc that manthey would be right on the money.As we both know they are not perfect either!![]
I do know what the changes are across the platform,as in ride height etc from the rake alterations etc
]I do know what the changes are across the platform,as in ride height etc from the rake alterations etc
Interesting that you mention the weights and rake RSR. I mentioned this in page 2 of the thread after having a similar experiance to yours. Think you explained it far more clearly than i could.
paul howells
New member
This may help,taken from the 964rs tech data service info book
Front
Total Toe +25,camber -1,castor 4.25 deg
Rear
Toe each wheel +15 per side,camber -1deg,15m
All factory photos show front and rear bars set in the middle.
Front
Total Toe +25,camber -1,castor 4.25 deg
Rear
Toe each wheel +15 per side,camber -1deg,15m
All factory photos show front and rear bars set in the middle.
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