Be sure to read the full article here -> http://dsportmag.com/the-tech/suspen...icle-handling/

Making your car handle well is a really complicated task if you overthink it. Ride frequencies, roll centers, camber curves, scrub radii; it’s enough to make you build show cars instead. So, I have an easy solution for you: ignore all of that stuff. Odds are that you can make your car handle better than most by knowing the following five things. Sometimes you can judge a tire by its tread pattern. In general, performance tires will have bigger tread blocks, since they are physically stronger and less likely to be ripped apart by hard driving



So how do you pick the right tires? That’s a tough one. The tire industry seems determined to make tire choice as difficult as possible. Tire names are a meaningless alphanumeric soup. What’s the difference between a Nitto NT01, NT05, NT05R and NT555R? The reality is that they’re all very different tires distinguished by a few changes in numbers and letters.



Having enough suspension travel is almost as important as having good tires. Think about this when you’re fantasizing about how low you want your car to be. Some cars, like the old double-wishbone Civics, have so much travel that you can be in the weeds and still have plenty of travel. Others, like the MAZDASPEED3, can hardly be lowered at all before they start pounding the bump stops.

 

very informative.

 

Thank you!

 

my original post was sarcasm LOL. but only because i didn't see the link hidden in between the pictures. i didn't realize there was more to the post. my apologies.

the chart for the coilover settings is awesome. everyone explains the procedure differently, which is quite confusing. being able to see the chart, in simple terms, is a huge help.

 

Haha, well thank you, we strive to supply our readers with the best information

 

it's appreciated.

so, regarding the chart... for each solution, is it suggested to make only one of the changes, hence why some have a choice in bold?
i.e. "left turn, corner entry push" has three options highlighted.

 

It's entertaining to see thought processes come full circle. I remember reading Coleman's articles in SCC and loved getting dragged into the technical aspects of suspension geometry. In a similar fashion, I've tried to step back a notch in focus as well and pay attention to the simpler things where 90% of the gain really is. Still fun to break out the modeling software and grind out toe curves based on different adjustments though.

#3 through me off at first as I was thinking weight balance, where you have very little control. But a few lines in I realized it was talking roll stiffness balance.

This is something I wasn't a big fan of though, "Instead of trying to reduce understeer, you need to think about increasing oversteer." This mentality amounts to "remove grip from the sticky end" which just makes the car slower. I won't argue the overall thought though, if the balance is wrong, the car with the excess grip on one end will be slower overall than if it was balanced out.



We've had a similar discussion on here too and CoG often seems to run right along with the travel argument. It at least seems to be more important than things like roll center and toe changes. Of course, if you can get it low, maintain travel, and have good geometry...well now you've spent 5X as much as #1 to #5 and you are 10% faster...

 

Thanks for pointing this out, Kaj. Sorry if this comes off a little unclear, the chart key points out that the choices listed in bold are the best or recommended changes to start off with. If the recommended change didn't cure the handling problem, one of the other alternatives that were listed might work better for you. Make only one change at a time, see what the result is, and record where improvements were made. Hope this helps!

 

One concern with these sorts of "quick diagnosis" handling charts is that they require the the user to make a lot of assumptions. I think it would be helpful if some of those assumptions (non-banked corner, even application of braking, relatively smooth road surface) are called out very clearly in this article, and either right before or right after this chart. That might help folks understand in what ideal situation these changes are being suggested.

I believe Mark Ortiz had put together something similar back in ~2003 when he was publishing his racer newsletters, and one of the main takeaways I remember was his suggestion of tuning shocks in pairs - diagonal or front/rear/ or left/right depending on the cornering phase. I have tended to follow this line of thinking, which leads me to question some of the recommendations made in the chart:

1. Corner Entry Oversteer: During corner entry (assuming heavy braking has completed, steering input has started, gradual throttle is being applied, pitching the car backwards and rolling to the right), the suggestion in your chart to increase the outside front rebound and/or decrease inside rear rebound. This doesn't seem to make sense to me, as the situation indicates uneven loading of the rear axle and increasing rebound damping on the outside (right) front shock would not help. Reducing inside (left) rear rebound would only accelerate the rate at which load is transferring off this increasingly lightly loaded corner, to the increasingly heavily loaded outside (right) rear and front end. This compounds the loose situation. Instead, logic would seem to suggest that adding inside (left) front rebound and/or reducing outside (right) rear compression would be the more suitable changes to make as the inside front and outside rear corners are most heavily contributing to the car's handling in this phase.

2. Corner Entry Push: Making the same assumptions above, I would suggest here that adding outside (right) front rebound would not change the attitude of the car much as this corner is seeing minimal change during this phase relative to the inside front and outside rear. Instead, adding outside (right) rear compression and/or reducing inside (left) front rebound would have more of an impact.

3. Mid Corner Behavior: Over/Understeer here would (again with major assumptions) indicate a spring/ARB/driver input issue more than dampers, as in true steady-state cornering the dampers are not generating significant forces. Damper adjustments here can be made to simulate stiffer/softer springs at the end losing grip but the potential trade-offs in the other cornering phases may offset any gains mid-corner.

Thoughts?

 

Not many people would be on throttle at entry.
Reducing inside, rear rebound would decrease the speed load is being transferred. It slows it down as increasing outside front rebound attempts to keep some of the load to the rear corner and lessen what's on the OF.
That should reduce pushing, if I understand it correctly.

 

Depend on the line. If you're going in deep to square it off and lengthen the next straight away, you may very well be picking up the throttle on turn in..

 

If the car is pushing in the situation you've described above (which sounds like trail braking), then the solution would be increasing inside rear rebound, not reducing it because the car is pitching forward, and that inside rear damper is in extension. Reducing rear rebound would hasten the rate of load transfer off the inside rear, and until that corner loses contact with the ground, it is transferring load laterally to the outside tires which would be undesirable at the front end.

During this situation (the car pitching forward still), decreasing outside front rebound would have no effect as that damper is in compression. As a secondary adjustment, the driver may consider reducing outside front compression instead to more evenly load the front axle.

 

the chart is a decent place to start, though. at least it helps show people general tuning guidelines and one can learn more from there. it seems that it was written based on a basic brake, let off, turn in scenario. if your car is setup for those, then it should work properly for most situations, given proper driver input.

 

great post, thank you!

 

thank you for this...bookmarking the article