Aftermarket springs?

I managed to find FHP fronts from Eurospares’s and HGTE 575 rear springs (also on Eurospares) that fit. Worked great!

 

What he needs more than springs is an updated Shock Absorber ECU (205619) and MSW rear 19 mm anti-roll bar. If you just change the springs, his 575M will be oversprung and underdamped.

 

I added Novitec/KW V3 coilovers to my 550 along with 19” Superamerica wheels and the results were fantastic. Image Unavailable, Please Login

 

Looks good. Did you notice any handing effect with the larger diameter wheels?

Everytime I think to myself "I can't ever do yellow", I see one that makes me change my mind.

Love the way your 550 stands out, and the Giallo compliments it's lines oh so well. How long have you had it? Hope you're putting ALL the miles on that thing.

 

I’ve had the car for 20 years. I decided recently to overhaul my suspension. I started by replacing all the rubber bushings, tie rods and drop links. Next I changed out the stock shocks and springs with Novitec/KW coilovers. Finally I moved to the 19” wheels and Skunkworks Steering ECU. The combination of all these changes have immeasurably enhanced the enjoyment of the car for me. The performance envelope has grown along with greater feel and comfort vs stock.

 

Agree with above. Personally I would do a stepwise charge starting with ECUs (MSW steering and the shock ECU Taz listed), and see how he likes it. This, of course, assuming all his bushings are good.

Then I would do MSW rear bar if still too much understeer / laziness in turns for his liking, only then (depending how he likes the balance) would I swap springs.

HGTC front/rears and FHP fronts are still available new (or were as of last month). FHP snd HGTC rear springs are nearly identical/ interchangeable (in process of confirming). Before just swapping parts, I would first see how he likes the balance as a personal tastes varies widely

You have to be careful with Eibach race springs on a 575 (or similar stiffness springs), as the risk of worsening/upsetting pitch/dive rate aka the damping balance is very easy on early 575s. And the spring sizes themselves rather standard….easy to source aftermarket but again depending on ultimate goal.

Final thoughts…good tires at proper pressures are critical. When I first got my 575, I hated driving it as everything was just subjectively wrong. In hindsight, a good chunk of that was due the cement brick 4?/5? year old Pirelli tires.

 

If he is considering coilovers, I worked with Fortune for 550/575 coilovers. I ran them on my personal car and it transformed the body control.
https://reidperformance.com/collections/ferrari-v12/products/550-575m-coilovers

 

You first need to know what spec you’re looking for (coil diameter/stiffness, overall length, ID/OD) then any race car/aftermarket catalog is where to start. I used that very approach to run custom linear springs on my rears for my last E31 (are you the same Timm from the E31 world? If yes, hello from the non-E31 side! ).

Just need to be careful, you can very easily upset the balance / dampening on 575s. Wrong length and you can blow your very $$$ shocks or make them useless by riding on bump stops. The damping for the 575 was step up goofy by Ferrari to address complaints of the 550 being rather unforgiving at the limit and overly stiff. The early nonFHP 575 were an over-correction. That is why correction of the underlying problem (shock ecu) was my first recommendation before swapping springs.

Technical spring data is in the archives from the workshop manuals but again know what you’re trying to do before making the car a under/oversteering or porpoising mess. Personally I would not go overly stiff as you will become under damped very quickly.

Mind you the technically simpler and ultimately cheaper (unless you can model/are good at math/and get lucky with the setup) is just get a coil over or ready made solution Ala FHP/HGTC

 

My apologies, user name overlap !
I’ll tell you more about the spring question later this year as if I can’t make the math work for my 456m w the assortment of OEM springs I have, will be going that exact route

 

I too was not happy with how soft my 550 felt, so I've since added MSC coilovers, MSW swaybar, and MSW steering module. These changes made a dramatic difference in the car and I'm very happy with the results.