[oceanvue]

Good stuff. Thanks. I'm starting to grasp that this is where I need to go. Precision and detail.

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[pure&simple]

>> Is there any advantage to continue to lower rear pressures ? At what point is too low too low?

Lower pressures provide a larger contact patch up to a point, and then becomes counter-productive. Watch the wear marks relative to the little wear-marker triangles that should be etched into the side of your tire. The top of the inner triangle is your target. Lower pressures until you start hitting that mark, although if you have too much rear tire (see my post above) you may never get there.

>> Maybe I just needed to raise the front pressures?

Raising front pressures relative to rear will change the balance of the car, but may not increase total grip. Both front and rear tires hitting their wear markers and with relatively even temps left/center/right is optimal.

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[wiseman]

<!--sizeo:5--><!--/sizeo-->[chassis first - then springs - then brakes - then sway bars - then alignment - then tire pressures <!--sizec--><!--/sizec-->

Chassis: Will have rear Yellow Sports on by weekend.

Springs: Stock. Should go to 225 with Yellow's Struts?

Brakes: Good to go......993 Brakes all around.

Sways: Have M030 w/ Delrin on now.

Alignment: Need -1 in back and -1.5 up front with Elephant Caster Blocks.

OK, so I may be out of line here or there, but adding Koni's up front w/225 springs ought to have me Good to Go up to the alignment, with maybe the addition of the lower Strut Bar.

Can I have an AMEN Brothers?

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[flash]

i would START with the lower bar - that is the key to it all - otherwise you are polishing a turd

chassis - stiffening, bracing, yada yada - having these things properly in place establishes what will happen as a result of flex - limiting the flex is the key to limiting the camber change under load

springs (this includes springs, shocks, struts, etc) - these things determine how the car loads itself and how eight tranfers - a 225 is the absolute max for any kind of balance with the stock torsions, and will still make a bit of understeer - adjust the struts for the 225# spring (probably about half way, maybe a touch more) - you'll know it's right when it dampens bumps, but isn't jarring - the compression setting is fixed on those, so no joy there - the rear shocks should not be set more than 1/2 turn from full soft for stock torsions, and has almost nothing to do with the front, though the natural frequencies of the ends of the car will no longer match, and you may find that you have to go 1 full turn from full soft to stop the car from "see-sawing" - this will be at the expense of some jarring in the rear, and a tendency to jump around a bit

brakes - while you might have the 993 brakes in there, even all around, balance is going to be everything - make sure the car is not nose-diving under heavy braking - it should drop nearly evenly on all 4 corners, with just a touch of front bias, and should not lock up the rear - this will establish proper balance going into a corner, which will prevent understeer and oversteer as a result of improper balance and weight transfer

sways - set to accommodate what the car does with the above conditions managed

alignment - set to accommodate tire wear and turn in after setting all above conditions

then go to tire pressures, using a temp gauge, and adjust until you get maximum contact on the tire, while minimize temperature change across that tire

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[wiseman]

Flash, Thanks for taking the time with this. I'll get the lower bar ordered in the morning from Pete and the Front Struts and springs from Jason at Paragon. Since I sense that you might think the 225's might be a bit much......200# better? Once this stuff is done..............other than fooling with tires which is pretty easy for me, I'm Done. So if it were you.............200# or 225#?.

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[flash]

happy to help - no worries

if it were me, and i were staying with the stock rear torsions, and not planning on adding any other springs back there, and running the koni yellow sport struts and shocks, i would go with 200# front springs

at that point, after adding the lower brace, if it were a car i mostly drove on the street, i would run the first set of non-stock specs listed here:

http://www.968forums.com/index.php?showtop...alignment+specs

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[wiseman]

Cool...........got it printed. Thanks again.

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[wiseman]

OK. I bought 2-- 9" Boxter Turbo Twists (ET55) and mounted the Yokohama 2354017 AD08's up front and 2554017 AD08's on the 9" rears. Got the Koni Yellows on Saturday.......1/2 twist from full soft. Reset the M030 rear bar to the outside hole. Tire pressures to start were 36 Rear and 38 Front. Course was at the airport yesteday.....lots of turns but one area where you hit about 65 mph before a turn.....so the speeds were higher than a typical parking lot autocross. First pass was pretty good.........same of most of the Boxters, ahead of the other P2 cars. Tire wear was right at the triangle's or 1/4 inch down on the shoulder. Second pass really good...............was my fastest of the day 46.11. Oversteer was very manageable. Tires were getting hotter so I had to let air out to maintain those pressures. 4th and 5th runs..........tires seemed to be fading....more oversteer was developing. Fastest time of the day was Danny Sheilds with a 42.1, Boxter S with Hoosier R-1's. My 46.11 won the class but as the day went on, the car got harder to control the oversteer in the corners and the times were in the 47.5 range. Afternoon got up to about 92 yesterday. I have the lower strut brace ordered from Pete. I'll put it on with the Elephant racing Caster Blocks when I get the front Koni adjustables from Paragon with new springs. Off to the alignment shop with Flash's specs and I should be about done. Once again, the racing tire guys really had an advantage...........didn't matter how hot the course got, those cars just barrelled thru those turns and never squeeled. Sure looks like the way to go.

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