Speedtoys

There's a good one or two underpasses in a curve here where a lowered or totally dead suspension 928 will wiggle left and right at both ends pretty disturbingly at speed, to the point that it will induce a quick 1-2- punch of under and then oversteer as each end reacts differently, and at different times.

No car is immune to this.

GregBBRD

Casper looks really low on that one corner.
That picture appears like the left front corner is around 75mm.

Casper had some version of an off the shelf 928 shock?
IE: Stock 928 Koni just re-valved?

IcemanG17

Doc
No.....casper has bilsteins custom valved with Heim Joints top and bottom.....they were custom made by the previous owner I believe..... I think the rest of the suspension bushings are stock

GregBBRD

I was almost certain that this was the case looking at Casper going through that corner.
Unless something was very wrong, stock shocks and associated pieces could never get that low.

BTW.....That right front suspension has over 1.0 degrees of toe out (~1/2" of toe out), at that height!
The "toe curve" on a stock 928 (173mm front ride height) is really fantastic....very little change in toe, through the operational range of the suspension. They did an exceptional job, at the stock ride heights!
And stays fairly reasonable until ~145mm ride height. (The stock shock "bump stops" are involved in the front spring rate at 145mm, so suspension compression is severely limited, below this number, on a car with stock length shocks and stock bump stops.)
Below 140mm, the toe curve gets terrible, very quickly...but by then, the stock bump stops are very involved in the front spring rate (and the cars are understeering enough (from the increased spring rate) that this height can not maintained for very long), so stock cars rarely get this low.
......However, in all fairness to Porsche, the cars were never designed to operate at ride heights or cornering heights this low

IcemanG17

Doc
I texted you the pictures of Caspers Heim joint suspension, its 4 pics top and bottom front-back.

I do recall putting on 1025lb springs in front plus a very high durometer bump stop on the shock shaft? Sean still says it bottoms out, but he does weigh just a smidge more than me :>

Honestly I never had an issue with rear suspension, only the front would bottom out....I did read an old post of mine that said it was set to 140mm front and 150mm rear using stock measurements.....

Whats funny is the Estate running stock shock top-bottoms had bilsteins with cut eibachs and it NEVER bottomed out in T8......it was quite low too...I guess the bump stops were working....it was only 4 seconds slower

Feel free to post the pics if you think it would help

Rob Edwards

For those that might not have seen it on Facebook, here's some beautifully shot video compiled by David Mavro from a marathon session at Thermal this week. The slow-mo footage is part of assessing suspension motion in the various turns there.

Constantine

Any thoughts from the pilot on the experience of driving this beautiful and capable 928 during this event?

john gill

I bet that felt good , the car looks very comfortable at high speed ,the stock suspension would not well done all thanks for the video

GUMBALL

Just curious, have you looked at a Race box ?? Something from Hewland or X-trac ?? I understand that these are non-synchro, but with a little practice, they are not a problem shifting.
OR, you could look at the selection of "paddle shift" options.

Just curious . . . .
.

Petza914

Have I, no. Once I fix the bearing issue in my torque tube I'm very happy with the Z06 trans setup I have in that car.

I'm not sure Greg, who put this Tilton clutch together, is on here anymore.

IcemanG17

I think this GTS 5 speed was totally gone through by Doc to handle the extra power and torque!