Will lowering the car mess with the brake vectoring on this car?

[VtecBuddy]

Saw this article today, and they mention how the car has ride height sensors, and the data is fed into the ABS module and the ECU to calculate tire load and brake vector accordingly. So does that mean lowering the car could mess with the brake vectoring tuning?
https://www.motor1.com/features/711587/type-r-engineering-deep-dive/

 

[Needs3Pedals]

I’m very curious about this sort of thing and also any effect that wheel spacers or non-stock offsets could have.

I’m too old to care about fitment but I do cringe a bit when people dive into that sort of thing without considering that they may be undoing some [presumably, hopefully] brilliant suspension engineering. Oh, and while I’m in “get off my lawn mode”, what is up with all these hideous aftermarket shift knobs?

I’m also sick of these little flaps on coffee lids. If you don’t want to spill your coffee you shouldn’t be driving with it.

 

[optronix]

I’m very curious about this sort of thing and also any effect that wheel spacers or non-stock offsets could have.

I’m too old to care about fitment but I do cringe a bit when people dive into that sort of thing without considering that they may be undoing some [presumably, hopefully] brilliant suspension engineering. Oh, and while I’m in “get off my lawn mode”, what is up with all these hideous aftermarket shift knobs?

I’m also sick of these little flaps on coffee lids. If you don’t want to spill your coffee you shouldn’t be driving with it.

The coffee lid gripe was a nice touch.

I'd be curious to find out definitively about these sorts of things, but based off what I understand now I don't think it's that big a deal. Lots of technology these days is "adaptive"; if I recall from the press kit on this car the dampers, VTEC, even steering are dynamically adjustable based on sensor settings. I'd like to believe that as long as the sensors that are feeding the programming are still functional after the modification (and the parameters aren't intentionally limited to factory settings), my guess is that the programming just adapts to the new settings.

This is truly fascinating stuff and to date I haven't seen any deeply technical literature on the topics. Part of which probably is that much of it is intellectual property (the rest is that I haven't necessarily actively looked for it...). The best I can recall is browsing some of the marketing literature on the DSC sport controller, which is an aftermarket augmentation to OEM functionality, so it isn't directly relevant to this conversation (and I still wish there was a plug-and-play offering for our cars....). But I'd really love to find out more on this topic.

In any case, there is substantial evidence that dramatically altering the factory suspension is not catastrophic to the driving dynamics of the car. In fact, I'm still deeply considering a set of Ohlins because that setup has been proven to significantly enhance the car's capabilities on a race track, even though it completely kills the adaptive components of the suspension.

 

[ABPDE5]

If you are going to dramatically alter ride height, etc., you might also want to consider pursuing the RV6 adjustable arms, some camber plates, etc., so you can dial in alignment post drop.

 

[optronix]

If you are going to dramatically alter ride height, etc., you might also want to consider pursuing the RV6 adjustable arms, some camber plates, etc., so you can dial in alignment post drop.

Right. Worth mentioning that there's only so far the software can take you.

But if we're just talking about your typical Spoon/H&R/Eibach 1-2" drop, I don't think that's really necessary... but also we're not talking about shaving tenths off our time at Laguna either.

 

[kjechel]

Saw this article today, and they mention how the car has ride height sensors, and the data is fed into the ABS module and the ECU to calculate tire load and brake vector accordingly. So does that mean lowering the car could mess with the brake vectoring tuning?
https://www.motor1.com/features/711587/type-r-engineering-deep-dive/

Very interesting article - Thanks for sharing. It sounds like it uses changes in dynamic ride height for brake vectoring and is probably feedback loop controlled, so it should be adaptive with respect to changes in static ride height.

Is brake vectoring (aka Agile Handling Assist) completely disabled via pedal dance? That's a subject of debate on the CivicXI forum. I think the only way to tell for sure would be to record brake pressure to each wheel and compare to brake pedal input. Disconnecting inputs to VSA is probably not a good idea as explained by @jayy_swish here.

 

[VtecBuddy]

Very interesting article - Thanks for sharing. It sounds like it uses changes in dynamic ride height for brake vectoring and is probably feedback loop controlled, so it should be adaptive with respect to changes in static ride height.

Even if it's using dynamic ride height as in it estimates tire load by measuring ride height changes, I'd still imagine ride height changes don't translate to load in the same way if spring rates are now different. For example, with a stiffer lowering spring, the same amount of load on a corner would cause less ride height change. It would get even weirder if we started thinking about progressive springs where the spring rate changes over the course of wheel travel.

 

[StingertimeNC]

Seems like this may only be an issue if we're driving the car at 100% of capability, which is pretty rare. Most of us are not talented enough to do that, certainly not on the street, maybe on a track. I'm lowered and riding on wheels that changed my scrub radius. I'm just out there enjoying it. Car still drives like a champ.

 

[IntegraSpeed]

For me it drives OEM on Eibach Pro springs and 15mm fr and 20mm rear bonoss spacers. I couldn't really tell any difference. i wouldn't worry about it.

 

[ZeroGSR]

Is brake vectoring (aka Agile Handling Assist) completely disabled via pedal dance? That's a subject of debate on the CivicXI forum. I think the only way to tell for sure would be to record brake pressure to each wheel and compare to brake pedal input. Disconnecting inputs to VSA is probably not a good idea as explained by @jayy_swish here.

Is it a subject of debate? Not doubting you, just haven't seen it myself and was doing some research on it earlier this week. Talking to the FK8 folks, they have confirmed that AHA only cuts in when running +R with VSA off, nothing when running pedal dance. But many still run +R because they claim slightly stiffer suspension tuning and they can mitigate the braking. That surprised me, but these are folks with far more experience than I (SCCA Nationals). I didn't feel any AHA cutting in personally when running pedal dance, but I am by no means an expert.