CliffsNotes: Suspension Tuning
#1
Stolen from a GRM. I ripped it out a while back and have been meaning to post it. Most of it is common knowledge, but I'm sure someone will benefit from it.

Corner Entry
Problem: entry understeer
solution a) soften front springs
solution b) soften front compression
solution c) lower front ride height

Problem: entry oversteer
solution a) stiffen front springs
solution b) stiffen front compression

Caution: Don't raise front ride height to deal with entry oversteer.
Important: Run front ride height as low as possible. While there should be no hard contact, it is okay for the car to lightly touch under braking or on bumps.

Corner Exit
Problem: exit understeer
solution a) stiffen rear springs
solution b) stiffen rear shock compression
solution c) raise rear ride height
solution d) stiffen rear anti-roll bar

Problem: exit oversteer
solution a) soften rear springs
solution b) soften rear shock compression
solution c) lower rear ride height
solution d) soften rear anti-roll bar

Caution: If the car works better when you raise the front ride height, the springs are too soft. If the car works better when you go lower, the springs are too stiff.

Mid-Corner
Steady state or mid-corner handling is affected more by the anti-roll bars than the shocks. In a car with zero front droop, setting the spring preload may be more effective than adjusting the front anti-roll bar although they work together.

Problem: mid-corner understeer
solution a) stiffen front springs
solution b) stiffen front anti-roll bar
solution c) increase front preload

Important: Mid-corner understeer is one of the hardest things for the driver to sense and understand. It requires a completely different fix than entry or exit understeer. In almost all cases, in fact, the fix is the opposite of what you would do for entry or exit understeer.
I Am Mike
4 wheels:  '01 RAV4 (Formerly '93 Civic CX, '01 S2000, '10 GTI, '09 A4 Avant)
2 wheels: '12 Surly Cross-Check Custom | '14 Trek Madone 2.1 105 | '17 Norco Threshold SL Force 1 | '17 Norco Revolver 9.2 FS | '18 BMC Roadmachine 02 Two | '19 Norco Search XR Steel (Formerly '97 Honda VFR750F, '05 Giant TCR 2, '15 WeThePeople Atlas 24, '10 Scott Scale 29er XT, '11 Cervelo R3 Rival, '12 Ridley X-Fire Red)

No longer onyachin.
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#2
RJ and I were just talking about this chart yesterday. Thanks for posting it, now I don't have to go look it up :-D
When it comes to Ryan Jenkins, the story ends with me putting him in the wall.

2009 Speed Triple | 2006 DR-Z400SM | 1999 CBR600F4 | 1998 Jeep Cherokee

-Ginger
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#3
i can't for the life of me make it work in my head where i understand how stiffening the front end makes the car understeer less in mid-turn. gaaah my head hurts!

but thanks for posting this up, though. always good to know suspension stuff.
2010 Civic Si
2019 4Runner TRD Off-Road
--------------------------
Past:  03 Xterra SE 4x4  |  05 Impreza 2.5RS  |  99.5 A4 Quattro 1.8T  |  01 Accord EX  |  90 Maxima GXE  |  96 Explorer XLT
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#4
Great info, thanks for posting that up. Smile
2010 Dodge Ram 1500
2019 Ford Mustang
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#5
Should be a sticky IMO =)
Posting in the banalist of threads since 2004

2017 Mazda CX-5 GT AWD Premium

Past: 2016 GMC Canyon All Terrain Crew Cab / 2010 Jaguar XFR / 2012 Acura RDX AWD Tech / 2008 Cadillac CTS / 2007 Acura TL-S / 1966 5.0 HO Mustang Coupe
2001 Lexus IS300 / 2004 2.8L big turbo WRX STI / 2004 Subaru WRX / A couple of old trucks
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#6
2 things:

1) i still can't figure out how my rear jack points (right in front of the wheel wells) drag in the carousel.
2) when i mean i ripped this out a while ago, i mean probably a year ago. it has been sitting on my desk ever since Tongue
I Am Mike
4 wheels:  '01 RAV4 (Formerly '93 Civic CX, '01 S2000, '10 GTI, '09 A4 Avant)
2 wheels: '12 Surly Cross-Check Custom | '14 Trek Madone 2.1 105 | '17 Norco Threshold SL Force 1 | '17 Norco Revolver 9.2 FS | '18 BMC Roadmachine 02 Two | '19 Norco Search XR Steel (Formerly '97 Honda VFR750F, '05 Giant TCR 2, '15 WeThePeople Atlas 24, '10 Scott Scale 29er XT, '11 Cervelo R3 Rival, '12 Ridley X-Fire Red)

No longer onyachin.
  Reply


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