dave-C2

Thanks in advance for guidance on a pretty basic topic.

Without sharing secrets, if there is a range for ride height that applies to the 981 CS what are those values?

Is there a tighter range for the difference between front and back values?

Is the ride height on the 981 CS measured at the same points as the street 981 GT4 as shown in the attached figures?

Dwane

Someone’s gotta have “the info” to help my buddy Dave out!

38D

Alignment starts to get into secret sauce territory, unfortunately. Same for suspension settings.

Chris P Lewis

A Google search revealed some 981 info:

Porsche 981 CS ride height rules

dave-C2

Thank you, Chris. Interesting minimum ride heights allowed in the Yokohama series.

MorroBay993

96 C4S with 73k miles, PSS10s at Front-2, Rear-3, Hubcentric 5mm spacers, Elephant front drop links and bumpsteer tie rods.

mikew968

Front:
• 75mm Minimum GT4 Cayman CS (981) (Appendix 4)

• Rear:
• 94mmMinimumGT4CaymanCS(981)(graphicforlocationTBD)

• Anyformofdriver-controlledrideheightadjustmentisnotpermitted

mikew968

• Front:
• 101mm Minimum GT4 Cayman CS “COMP/Trackday/MR” (982) (graphic for location in

Ground Clearance of Vehicle section.) • Rear:

• 94mm Minimum GT4 Cayman CS “COMP/Trackday/MR” (982) (graphic for location Ground Clearance of Vehicle section.)

• Anyformofdriver-controlledrideheightadjustmentisnotpermitted

mikew968

With the required setup for the 718 running Sprint challenge, won't the car understeer like a big dog?

dave-C2

I don't know how different the 718 suspension is from the 981, but I found some technical regulations for the 981. The Yokohama Cup 2021 series and the PCA Pirelli 2017 series used different reference points for measuring front ride height. Yokohama cited the suspension bolt head that is used for the street car, but PCA Pirelli used the bottom of the body cross member just aft of the bolt head. They may have chosen the cross member to make it easy to slide a gauge block under the car to check ground clearance.
The minimum for the front PCA Pirelli was 79 mm and Yokohama was 81 mm.

For the rear ride height I found only the use of mid point between attachments of the diagonal brace, as used for the street car. Am I correct that the measuring point is the inside top of the brace? The minimum for PCA Pirelli was 105 mm and Yokohame was 94 mm. The V.2 version of the Yokohama regulations includes more illustrations of the measuring points than V.4.2, but they are both consistent with the street car points.

The set up advice for the GT4 MR dated 28.03.19 (which I presume is for the 718) has recommended ride height of 88 mm and 105 mm F/R for use with Pirelli slicks.

Hope some of this is useful.

mikew968

i am supposedly at 85/105 right now but have not verified that the right measuring points were used. The car turns in pretty well but as I get into more than 7-8 HC's on the Pirelli slicks the rear starts to oversteer as you lean on the car and apply throttle.

jbaker136

The setup on delivery for the 981 Clubsport was 79mm front and 105mm rear measured at the front suspension point bolt and rear crossmember shown in the pictures below taken from the Technical Manual.

coryf

The SRO measuring point is about a 20mm difference vs the front bolt head that the manual lists. I'm guessing this is where the discrepancy is. The 94/104 number I think came from the sro bop table.