Parr or JZM - Guidance Sought Please

[housemaster]

henry-f said:

A most enlightening thread

What does the panel suggest we do with rear toe?

Henry

Agreed, it has been a good thread with the detail and input I had hoped for, thanks everyone!

[DanH]

fergus said:

housemaster said:

Forgive my ignorance, but explain rolling the rims?

On a std car, if you feel under the wheel arches, you will feel a return lip of the outer wing point out perpendicular to the wing, i.e. run parallel with the top of the tyre. This may only be 5-7mm for example.

When the arches are 'rolled', this return edge is rolled back to be flush with the outer wing, i.e. folded back on itself up inside the wing. This allows a lower ride height to be achevied, as the tyres are less likely to touch the return edge of the wing. If you run your finger round the inner wing wheel arch of a 964RS you will see there is no protruding return edge. It takes nothing away from the car at all, and I suspect would be missed in 99% of all 'inspections' done on cars being bought/sold. It only sugests that the car has probably been run with lower than std ride height. On some occasions there are tiny signs where the rolling has taken place, but often this isn't really visible until you're up really close.

A full description of Ackermann angles and bumpsteer (set after you've decided upon the correct Ackermann effect you want to run) can be found in Allan Staniforth's 'Competition Car Suspension' book. Well worth a read.

Some people with rolled arches are having trouble keeping in possession of their arch liners, which seems like a potential downside to me.

[S1XXR]

Hi HM

I have a fast road setup courtesy of JZM. Immediately more composed and neutral.

Don't forget tyres make a massive difference. I am a big fan of the Pirelli Corsa System. This is a track compound tyre but still road legal...works brilliantly in the wet too. This was the OE tyre on the 996 RS.

Compared to standard road tyres (eg Pilot Sport II's) they are much grippier and ultra precise. Wear rate isn't too bad either. All in all the best enhancement that money can buy for a GT3.

For hooning in the alps + a bit of track work, Corsa's and JZM stage 1 will be just the job.