Ronnie

excuse my ignorance.

I'm presuming these ducts improve braking performance. If so, any of the more learned on here able to put a % on the improvements on could expect?

Dr. Car

I querried my HAL 9000 about this. "He" says you'll experience 18.273035% improvement, translating into a .082382183% better lap time.

mdrums

Techniqually on paper they should cool your brakes better. On the street you will not notice a thing. Track guys might see some better brake cooling.

Ronnie

Thanks for the intelligent response. Greatly appreciated.

RonCT

My guess is that they designed the "normal" ducts for all 997 products first. Then as they developed the GT3, they might have spent a little more R&D and testing time on optimizing brake cooling. So although the surface area might not be significantly different, the design could channel and concentrate airflow a little better. That's my hope. I will say that the oem ducts on my 997s did a fine job at Watkins Glen this week for Cups & Saucers. I went out in every session so that means I was out approximately 7 hours in the 2 days (30 minutes on, 30 off). Some were cut short due to "incidents", so maybe 6 hours total of serious track use. No fade, no glazing, just fantastic stopping power. So street guys - don't think this is a must have. Track guys - ditto - but for $40 it's worth a try for me...

NVRANUF

That $40 bucks pales when compared to the expense of tire wear.
Also, the expense of tire wear pales when compared to the fun adrenaline factor lapping has!!
That said,....I would guess RonCT is soon due for a new set of rear tires...

Crazy Canuck

For $40 I might order a set.

RonCT

Curiously, the PS2s are wearing very well. Rears are 6/32 and 7/32 remaining and fronts are 6/32 and 7/32 respectively too (I should have swapped left to right sooner to even things out). I think that's pretty amazing given my 3 "warm up" events (ultimately 1:03s at Lime Rock), my son having his 1st 2 events (1:15-1:20 at Lime Rock), and about 6 hours on track at The Glen (ultimately 2:17s).

NVRANUF

That's great on the MPS2 wear! There's hope that my new 305's will last the three PCA DE events plus whatever "casual" lapping events I find my way into this season!!
When I look at times like those, all I can think is, wow those must be short tracks compared to the new track at Calabogie.
I guess we're just spoiled!!

RonCT

Lime rock is 1.53 miles and Watkins Glen is 3.5. Max speed at The Glen was 143 and average 88 MPH. The PS2 really can stand up to some hard work - but only if you treat them well. The shoulders are definitely worn down, but there's still plenty "inside" tread for street use (though not the best looking tire - then again, if people point and ask why the shoulders are gone, I can bring up the track).

mdrums

Ron, did you change out the brake fluid in your car?

RonCT

Yes, SRF. Expensive stuff, but what isn't for these cars. $75 for SRF vs. $15 for regular - so it was a $60 bump...

mdrums

Does it really help for a soft brake pedal? I am going to switch in a few weeks before my next DE.
Thanks, Mike

RonCT

Hmm... I think a soft pedal could mean a few things. Soft pads, worn pads, fluid spent, etc. I've never had an issue with fluid - I've always had it changed 2 times a year - before spring DE season and before fall. If you haven't changed it out recently, it's a great idea.

I don't know that SRF is needed - I'm guessing something like Motul 600 Race or even ATE 200 would be fine. I used ATE 200 in the M3 and it never let me down. I went with SRF because that's all that Farnbacher would use.