Brake Pad help

[jasonoehler]

Hi fellow racers. I've just picked up my Rush and have done about 1.5 days at a track I'm very familiar with. I did the brake bedding with engine break in on first session. As i started to push the car, i developed a long brake pedal. Not fade, but just not much stopping power. After discussion with David, I did an abrasive treatment to the pads with some of the finest concrete in SW Michigan (no sand paper available).

Sure enough, the next session went back to the long pedal travel, almost no initial bite on the braking. I have the bias at 58% front. This track is not a heavy braking track either. 1 moderately heavy braking zone, 2 moderate. remainder are mild braking events.

So, I'm guessing its my braking style... Has anyone done research on different pad compounds? (I did do a search here, couldn't find anything...)

Jason

 

[JChapman]

I’m still adjusting to my new Rush SR as well. I found the back end unsettled at 61% front bias and comfortable at 59%. I tried 57% during my last session and noticed poor braking performance. I couldn’t say pedal movement changed but definitely reducing stopping power. I’m back to 59% and will make smaller adjustments from there. Try a bit more front bias.

 

[DrPyro2k]

The stock pads don't have a significant amount of initial bite. They are cheap, and will last a considerable amount of time given the weight of the car (even longer with front/rear rotation). A side benefit is that you do have to press "harder" to get the wheels to lock up, which helps new drivers that have relied on TC and ABS to save their bacon on track. There are a few posts around here that note a couple of other options. I was also use to much more initial bite, so I swapped to PFC-11 pads. They are 4x more expensive, have MUCH more initial bite, you really do have to focus on brake pressure and release as you will tend to over-brake, AND you may have to do a small amount of shaving to get them to fit. I have lots of years running PFC on track and swear by them, so it was the one and only pad I swapped it. As I noted others have their favorite, need to search for the post...


See here...

https://rush.sr/threads/brake-pads.157/

 

[jasonoehler]

Thank you guys for the objective feedback. I'll try the brake balance adjustment. I've ordered a set of DTC-60 pads to see how i like them. I'll consider the PFC next. I've not run ABS on a racecar, so I'm pretty comfortable with with this, and want that initial bite.

David, the link won't let me open, need permission?

 

[PizzaDude]

I run PFC 11 and they are great pads.

 

[steven_d]

Two other pad options are: Cobalt XR2 or XR3's, or Carbotech XP-10 or XP-8.

Disclaimer, I don't have a Rush (yet) but I do run a Lotus Exige which uses the same pad sizes so I know they are available. Cobalt and Carbotech are popular options in the Lotus community. I personally run Cobalt XR2's and XR3's and have liked them quite a lot. They definitely have a strong initial bite, modulation is good too, and since they are a sintered pad the bedding process is less stringent.

 

[Sam Reed]

I have found that the bedding process matters to an extreme degree. My first time around on my DBW car I was going it at the same time as engine break-in and apparently I screwed it up. I put in a fresh set and concentrated on bedding and the difference was night and day.

I wouldn’t discount the idea that you’d be more comfortable on other pads, but it may be worth giving a new set another go as it is hard to beat the price & longevity.

 

[PizzaDude]

I didn’t dislike the stock pads. The car stopped great after the initial harder pressure. I just have issues with my left foot and pushing so hard wasn’t great for it so I switched to a pad with more bite. Now I dont need to use as much pressure which helps

 

[RushR.Rentals]

I have no problems at all with the stock factory pads.
when I bedded in the pads is wasn't at the track when breaking in the car I bed them in before hand. the reason is with being on track there is no real good way to bed pads in. you can't adjust speeds to do it properly and then let the brake system cool back down.
if for any reason you over heated your brakes this will give a long peddle feel. when we take delivery of our cars one of the 1st things we do is flush the brakes system and refill with the brake fluid we use. I'm sure the fluid the cars come with is fine but this way I know just what's in the car. if you over heated your brakes the peddle may at time come back but as soon as your on track again the peddle will got right back to being soft the second they start to get a bit of heat back in them.

 

[jasonoehler]

thanks again for more objective feedback. I'm just back from the CMP gridlife event. Wonderful event, BTW!

My brakes were an issue all weekend. long pedal, minimal initial bite. I'm planning to do a full fluid flush as recommended here. Everyone i spoke to at CMP was very happy with the stock pads. So, I'll try a bit more with them and try the DTC 60 if still not happy. Thanks again!

 

[RushR.Rentals]

wow a DTC 60 on a car this light weight ?????? at most maybe a 30 even at that I would be surprised if you could get the brakes up to the proper operating temps.
one thing you may want to do is take your brake temps. our temps with the stock pads are falling pretty much in the sweet spot of the temp range of the pads.
the stock pads do not have a lot of initial bit but they do get a bit better with that once the pads get up to temp.
one thing about driving a momentum type car is to use your brakes as little as possible and when you need to it's light braking.
if you have gone through all the cars brake line fitting and made sure every connection is tight with no leaks either leaking fluid or sucking air.
and you know your system is all good you can adjust the two rods from the peddle to the dual masters. this will give you the peddle travel you maybe looking for.
what I like about the stock pads is they have linear feel with the peddle to the braking force until the tires will lockup.
what I like about these stock pads is when I want to be on the throttle through a corner but I want weight transfer onto the front wheels to get the car to turn in. I can be on the gas and just touch the brakes for a second if the brakes had more initial bite this would still be doable but a bit harder to do.

 

[Bill Wright]

"you can adjust the two rods from the peddle to the dual masters. this will give you the peddle travel you maybe looking for."

Can you expound on this statement?

 

[jasonoehler]

Update: Full fluid flush did not help my braking issues. At Mid Ohio, same issue with the long pedal and poor feel. I switched the front only to the DTC60 and my braking experience was completely transformed! They were absolutely perfect for my braking needs. firm pedal, right at the top. great initial bite and easy to modulate release. no fade. this is the pad i'll be using going forward. Whether i switch the rear pads to DTC60 or something other is TBD.

Thanks again for all of the inputs.