As the title states , how low can we go with adjustable M030 s in the front and indexing the rear bars . Do ya run the front and rear ride height even or a little rake ???? I was thinking indexing the rears ( 25.5 solid bars ) and then scaling the car , and adjusting the fronts to get my corner weights .........I know alot of that will depend on spring rate so every car would be different , but just trying to get the lowest possible without having to shorten the shocks .........

 

The M030 perches go pretty much as low as you could want. The target would be to get the control arms roughly parallel with the ground. Personally I would run with the front and rear height being equal. The softer your springs the higher you have to run to prevent the shocks from bottoming.

 

hi Jason
I understand the principles ....... the lower the more spring rate you will need and the shorter shock you will need .... Just trying to get a starting point for when i install the new 25.5 rear bars in a few weeks . i want as low as i can get , with out bottoming the shafts , Konis front and rear . We'll put the car on the scales for final adjustments . The springs for the M030 i have are the single red dot , not sure of the rate but i think they are around 180 # or so as I'm not sure the difference between 1 2 3 dot reds ....... Working on stayin legal for e stock .

 

I throught spring rates were free for E stock. You are going to have a tough time staying off the bumps stops with stock spring rates and r-compounds regardless of the spring rates. Also what control arms are you running? You will have problems with ball joint binding issues before you you'll have shock issues.

 

No ... i wish ....... unfortainatly springs are not free , would bump the car to CSP or SM . I need to figure out the rate for the M030s package for the front . Steel front A arms . I will have to look at the rules , but i think i can run " improved " balljoints .

 

Like I said Id start with the car lowered to the point that the control arms are parallel to the ground. This is where my 924S was set when I had the OEM springs (now I have 400# springs and Im a little bit lower) and I was very happy with how the car handled on track (never autocrossed it) except that since I have a 924S and didnt have much camber at the time my tires would run on hard right handers.



Spring rates for the M030 cars are int he factory manuals. The early M030 cars were 140# springs. The various tolerance groups are given in the manual.

 

Sorry thought you were talking PCA club racing - is this for SCCA AutoX?

 

Yes . Trying to optimise what little the rules give me . I have not yet run the a arm through its travel arc , what issues will i see ? What about any strange geometry changes in the rear ? Any good reads on the subject ?

 

Thanks . Found the rates in the FSM you gave me . Not used to metric n mm . What sized wheel and tire for reference sake .

 

Wheels were 16" phone dials. Rear tires were 225 50 16, front were 215 55 16 IIRC. The rates in the manual are N. They also give you a compressed length that you used so you divide by that to get N/mm and then there are conversions for #/in. They are around 140# springs for early cars.