Clutch dump at 5000 RPM?
 

In at least three reviews of the BRZ they talk about how to launch it. They all seem to conclude that dumping the clutch at 4500-5500 RPM is the best.

Well that seems kind of hard on the car to me. I have not tried it yet.

How about you guys? How long with the clutch last if you do that regularly?

Pat

Dumping the clutch regularly is not good for your car. For any car. Don't know why you'd want to do it regularly.

there is no situation where you could possibly dump the clutch REGULARLY but you have to do some pretty fancy feathering when you dump the clutch at that high. I'm real inexperienced did that and just did a pretty nice burnout. I launched best at 3500

((RPM / curb weight) * # gears) * # tires driven = 22 times ok?

IMO the true acceleration of this car happens to be launching this car around 3k rpms. I saw a video of a manual BRZ launching at 3k rpms and it got to 60 in 6.8-6.9 seconds.

that's pretty slow still. Motortrend did a 5k launch and got 6.2. Another company on here did redline launches at the drag strip and did a 14.7

Yeah but I was talking about playing it safe on a daily basis.

Around 4.5-5 was best for me with 235 ad08s so 3.5 sounds faIr for the junk oem tires.

Understood. It's a gamble either way. One guy might break something on the first dump, and another guy 8 years from now with 100k miles on it will done several clutch dumps and have no issues. Its one of those things to me that is hard to measure the wear. To many variables. Like when people say redlining your car causes more engine wear. I redlined my S2k a couple times a day for the 5 years I had it and 100k miles, and compression test and leak down was perfect before I traded it in.

All hard launches are rough on the car. A high rpm quick slip is for drag racing. You only need to do this at a prepped strip.

So what is a quick slip??

Some of the more serious autocross guys have done dozens of hard launches on sticky 245+ width street tires so they should have some insight on this. I believe axles might be an issue.

The last time I autocrossed, I did a hard launch at 3500 rpm on mild 215 width street tires and got mostly wheelspin in 1st. That was pointed slightly uphill too.

If you're talking "clutch dumping" it really makes you look like a goof.

As for properly launching the car, I run 245/40 Bridgestone RE-11A in Autocross and I launch it at 4000. There is no "dumping" the clutch, I feather it while keeping as close to wot as possible and accelerating as fast as possible without spinning the tires. 5000 would be better as the engine would be out of the "torque dip" and you would achieve the best possible launches there. I just limit my launches at 4 and save the wear and tear and take the .1 second loss.

Properly launching the car just wears your clutch faster, "dumping" it is slow and with sticky tires you will break things.

I autoxed my Integra GS-R (140-190k miles on the odometer) for 4 full seasons and would usually launch around 4000 rpm. At the drag strip (15-20 runs total) I would launch around 6000 rpm. And just for kicks a few times on the street I've launched as high as 7000 rpm. Never had any related drivetrain wear issues. I had the inner axles replaced 6 months ago (car currently has 300k) but that's normal at this point. Also I've got over 150k on this clutch, and still doesn't slip (OEM clutch, 2nd on this car).

:burnrubber:



I think the BRZ should be fine launching at 4000-5000 rpm without having to worry about drivetrain components. However I would be leery of Subaru agreeing and honoring the warranty "IF" something were to break.