DSC Magnaride Controllers - Issues, Tunes, Experiences?

[TeeLew]

I've had several guys on my DSC maps. Everyone went quicker than the stock controller. A couple guys picked up like 2-3 seconds a lap. Keep in mind, I didn't make their car that much faster. I just made them more comfortable to hustle a car with insufficient front spring. A pro driver would have noticed the difference, but the gain would have been much more modest.

It's not a great choice on normal roads. If you get it good on the track, it's too stiff on the street. If you soften your race stuff to make it OK on the street, then it doesn't have the ability to control the bumps as well, particularly freeway rollers. The Magneride controller has the street stuff dialed. They have about 3x the tools in the OE controller that you have in the DSC. They can ramp damping in and out in ways you just can't do with a DSC. Every once in a while, the DSC might throw you into limp mode just for fun. It's just a quick OBD2 reset, but it's annoying. Sometimes it won't connect to the software in your computer. Sometimes stuff just randomly gets corrupted and you have to rebuild your map from scratch.

Here's the kicker, if you're really worried about lap times, there are several passive packages that will be faster than the Magneride dampers ever could be, regardless of tuning. DSC was working with the Tractive racing damper company to make an active race package. It was a lot of cash and the valving that Tractive spec'd was garbage. If they would have had a better damper valving, the entire package might have worked a little better. As it was, the juice was not worth the squeeze. The rear springs they told people to run were significantly too stiff, IMO (I know, I know, that's *always* my opinion). The biggest gain I had on the car I worked on with them was dropping the rear spring rate. The guy wouldn't drop it as much as I wanted, but at least he was letting it move a little. All the sudden the thing wasn't beating him up so bad. Dampers can't control the motion if the springs are so stiff you're just bouncing around on the tire.

 

[byronj]

@TeeLew I had to do an entire set up to get my car capable. I know what youre saying. DSC did not put any time into this product. It has potential but you need someone that can engineer it right. As I stated my Best Friend (BFF) is a racecar engineer on a few teams so I am lucky to have his knowledge. If I didnt I would have junked these. And FWIW, I got these BNIB for 2K. So I had to try them out. I am more a MCS guy. I go bi and tri way. Depends on my orientation for the day( LOL)
What TeeLew is saying about set up is 100% accurate. My set up is great for the track. If and when I have to drive my car on the road, well its so crappy that when I hit bumps my foot just makes the throttle jump with the bumps.

@Junkyard Dog see my attached screen shot. I dont see DCS doing any S650 things. Thats not saying the controller cant be set up but id make sure its doable with the S650 platform. BUT>>> IMHO the best solution to a Dark Horse issue is a GT350. BWAHAHAHA!!

I have a buddy on here that went with a certain hybrid coilover set up and he wanted to get the DSC. I told him not to waste his money because it wont work unless you have the person to program it. He sated he can get programs from some guy. But that really means nothing.

 

[mavisky]

As others have said for track work the stock cars dont have enough rate. By the time you factor in springs, front camber plates, and a DSC unit youre already a good step of the way towards a decent set of quality coilovers and you'd be much better off there. I tried to make it work, had moderate success, but moving thr the MCS coilovers was a night and day difference.

 

[SlowstangGT]

Chiming in on my feedback with a 2018 GT350 and the Steeda DSC (the locked down tuning) + 350R dampers + Steeda Dual Rate Springs + Steeda Comp Sway Bars (front set to second softest, rear set to middle - this is the baseline Steeda suggested I start with)

This is my third track day with the car, all at Sonoma, and first time with the Steeda DSC - the other times I had driven it with the OEM 2018 GT350 controller on the Dual Rate + Comp bars + 350R Dampers - the GT350 controller on the R dampers might have exacerbated the compression issues i'm about to talk about below.

The main benefit over the stock controller is that the compression damping under braking is a lot less - the past 2 track days I was going into ABS ice mode on the Sonoma T7 braking zones under hard braking, which was confidence draining. The softer compression damping under braking added confidence this time, and I was able to go a full second faster than before, though I wouldn't attribute it to the DSC making the car faster, only that it made my confidence go up

However, the compression damping in Steeda's DSC tuning might have gone too far the other way - I now scrape my front lip on the slight rise at Sonoma T11 (though I can definitely fix that by braking later past the rise once I'm more comfortable with the car). As a stop-gap, I'm considering adding skid pucks to the underside of my front lip

Steeda's rebound damping feels pretty good, though I for sure am not knowledgable enough to want adjustments made to it one way or another.

Imo, it's a pretty good idiot-proof set-and-forget tune for those who want to maintain the benefits of one-button switching from street to track damping. Street mode is borderline too cushy / too much travel (underdamped) but nice for rough roads. Sport mode is great for smoother pavement, and has a "fun" amount of rebound damping baked in

However, I'd probably go coilovers if I towed it to the track. The main pain point for me is the lack of ability to put a stiffer front spring past 400 lb (with the AJ Hartman magneride coil spring kit), which is a turnoff for anyone wanting to add aero

As an aside, @byronj I need to hit the track with you again soon!

 

[TeeLew]

However, the compression damping in Steeda's DSC tuning might have gone too far the other way - I now scrape my front lip on the slight rise at Sonoma T11 (though I can definitely fix that by braking later past the rise once I'm more comfortable with the car). As a stop-gap, I'm considering adding skid pucks to the underside of my front lip

Try this:

Approaching T11 full-throttle. Lift the throttle completely before the rise (on the upslope, not at the crest) for T11. Not some lazy 4 second lift, but a proper throttle chop just like you'd do if you were going to brake, but don't brake. Just coast for long enough that you clear the rise and the car settles on the downslope. It's only about 50m. Then brake with the car going just a little slower (due to the coasting) and much more in control (because you haven't put a bunch of pitch in the car, yet). You'll be able to move your braking point later and carry more speed to the apex. Seperating the throttle lift slowing and brake application slowing will also help reduce the nose-dragging.

That's the short, "How do we make it work this weekend" answer.
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Now what you don't want to hear.

Ultimately, IMO, the Steeda spring rate combo are tough to make work. The initial rates are 200 #/in front and 800 rear. Main rates are 350 front and 1200 rear. They are dual-rate springs, which means there is a step in the rate which makes the car have a variable roll couple depending on where you are in the travel of each end. On entry, you're 350 front/800 rear. As the car rolls into the corner, the rate goes from 800 to 1200, which is going to feel like absolute dog-siht. Unless you've got a damned good reason to do otherwise, I always recommend linear springs and motion ratios. If you have to have a step in there somewhere with bump-rubbers, then make sure the car is either all the way into them through the corner or all the way out of them. The fewer non-linearities we introduce, the better.

Forget vehicle dynamics and handling balance and oversteer or understeer. Imagine it's 1930 and we're racing a Grand Prix car in Italy somewhere. We really have no idea about the physics involved. There are probably all sorts of wives-tales on what makes a car good or bad, but nobody writes it down. What we know is when we're braking hard on the racetrack, we drag the nose of the car. What should we do? We don't want our car dragging on the ground, whether it's causing damage or not, becasue it's taking weight off the tires. Would they have put sacrificial wear pucks on the car? No, they would have stiffened the front spring and/or raised the front ride height. That's exactly what you need to do. Sometimes the obvious answer is the correct one.

Steeda Dual Rates drops the front and the rear 3/4" (which leaves a bunch of unhelpful rake in the car), adds not nearly enough front spring, goes to the top of the range of what might be necessary on the rear and then tries to Jedi Mind-Trick everyone into thinking a car should handle like this.

Your problem isn't just that you're not 'comfortable with the car', it's that the car is uncomfortable enough that you're feeling it and it concerns you, even if just subconsciously. When you go to the brakes, the front platform should be well-supported and not dive excessively. It should give you something to push *against*. You shouldn't feel like the car is making this big pitch forward with the splitter digging into the pavement and the rear tires are hanging on by their toe-nails. The rear will always rise, but it should feel controlled without the trying to skip over the top of ripples or seams. It should be able to absorb them to some extent. It needs to have some compliance. You NEVER want to be chasing the rear on corner entry. We want the car to be stable so we can confidently carry speed into the corner and crank on the steering wheel without being constantly aware of having to catch the rear when it slides. It should do its rotation in the late-entry / middle of the corner which will allow us to open hands and go to gas. If we have too much rake in the car, too soft of front spring and a healthy (I won't go so far as you say too stiff, especially considering T6) rear spring. You just need the front rate and ride height to match it. Which is a bit of an issue...

Swapping over to AJ's setup on the front with a 450 #/in spring would be a good start. It raises the front ride from stock about 5mm, but that's fine, we need all the rate we can get and this is the best 'easy-button' compromise. The problem with 450's on the front is that your 1200 #/in needs more than that. I wouldn't run less than 600#/in front with the 1200 #/in rear. It's not that the rear is crazy high, but you just can't get enough front to match it.

So what do you do to the rear? I'd shoot for an 800-to-1000# rear spring with a ride height about 1/2-1" lower than stock. Steeda Ultralight linear would be an option. They are 800 #/in and drop the rear an inch. I might stick a couple shims on the top of the spring perch to raise the rear of the car after the first time out if it was too pushy. The other option would be AJ's rear kit with race springs, but I don't think that's quite warranted, yet.

The first response to my spring recommendations is always, "It'll make the car have a massive understeer." It won't. Roll couple distribution is *a* factor in handling balance, it's not *the* factor in handling balance. The first thing we need to do is control the motion of the chassis due to the terrain and driver inputs. Reducing overall front motion with a stiffer spring rate reduces the negative effects of the mediocre camber control of a strut suspension. Controlling camber is a bigger deal than adding front roll couple distribution.

The rear isn't nearly as sensitive, because it has and upper and lower arm and a better camber control curve. On the rear, a softer spring will allow better traction off all the slow corners and a more confidence-inspiring rear everywhere. If we get a pushy balance, stand up the rear cambers a couple tenths, straighten the rear toes and trail brake more.

OK, I'm done writing. Good evening, Gents.