Black & Tan 332iT

[Bry5on]

Is there a book you'd recommend to those who are not engineers who want to learn more about vehicle dynamics and how all these factors (roll axis, CG, multi link vs trailing, frequency response etc) that affect how a car feels and handles?

Race Car Vehicle Dynamics by Milliken and Milliken is my favorite: https://www.amazon.com/Vehicle-Dynam.../dp/1560915269

These days there are also lots of great YouTube videos. More recently, the Suspensions Explained Channel has put out a few great videos.

Ultimately the best way for me to understand is to experiment on my own cars by isolating and changing one variable at a time (you see lots of that in this thread, despite the effort of doing jobs twice or even more times). I had an e31 850i manual that I turned into a corner carving monster that used to clean up e46 M3s at autocross after reading the book above and incrementally experimenting until it was great.

[YoitsTmac]

Is there a book you'd recommend to those who are not engineers who want to learn more about vehicle dynamics and how all these factors (roll axis, CG, multi link vs trailing, frequency response etc) that affect how a car feels and handles?

[Bry5on]

Well. I'll. Be. Damned.

All this time I've been calculating the roll center height of the rear as something astronomical and offensive at ~12" versus a nicer 4-6". After re-running the analysis, I'm calculating a rear roll center height of about 130mm or just over 5" - just about where it should be.

Turns out I'm the fool and I've got egg on my face for making a bad assumption. The roll center height is *just fine*. The front seems to be about 40mm high, so you might argue that a rear roll center closer to 100mm might be better, but you'd be splitting hairs.

Now, the toe control and ride comfort balance still sucks, and the suspension is still heavy and high inertia so there are still gains to be had from the e39 suspension, but the geometry isn't likely to be one of them...

[Bry5on]

Modeled the e46 for fun, now I can do a real analysis of camber, toe and track changes at some point

[Bry5on]

What would it take to get / make a Mullet tune for those of us w/ CSL airbox + CSL software and different cams (288/280s)? Been doing a LOT of reading about datalogging, tuning, etc.

Mike

Realistically pretty unlikely. Either an engine dyno and a lot of time, or I’d need to daily that setup and iterate for several months. Sorry!