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View Full Version : Who here is using the two step rev limiter?



Matz
10-02-2007, 11:25 PM
I'm thinking about enabling it just to see what it's like... but I don't know what a good value is. On evom, some people seem to think 5900RPM is the magic number. I'm also curious to know how much this will f up my Evo, because I don't need the feature, but wanted to play around with it.

earlyapex aka jack ass
10-02-2007, 11:33 PM
I used 5350 at sac raceway when I went car bowling. I probably should have used 5500 or a little higher to get a little tire spin to be nicer on my drivetrain.

gohdunlam
10-02-2007, 11:33 PM
mines at 5500....i think your suppose to match to some part of your peak hp or torque or something like that? iono but i think it would be nice for you to have...

steevo8
10-02-2007, 11:37 PM
what do you guys think I should set mine at?
http://i69.photobucket.com/albums/i45/ssleevin/DSC00944.jpg

Matz
10-02-2007, 11:44 PM
I actually think it doesn't have to do with a specific torque / HP number. I would expect to need to factor in things like tire temp, coefficient of static friction for the rubber you're using, tire pressure, and the weight of your specific Evo. Once you have these numbers, then given the car's power numbers you can decide on a rev limit... ????

Matz
10-03-2007, 06:33 AM
So no one is worried about possible damage from using the two step rev limiter?

I've never done it before, so I guess the idea is to simply stay stopped, press the clutch all of the way in, go WOT and drop the clutch? Scary. :shock:

steevo8
10-03-2007, 06:43 AM
I wouldnt just dump it.. get the clutch to just barely start to engage without moving the car then when its go time slip it just a VERY VERY small amount and then let off. You can find a ton of vids of it. Also when I say slip it, its very breaf. roughly just enough to get your car to roll a couple inches, thats all

Matz
10-03-2007, 06:48 AM
I wouldnt just dump it.. get the clutch to just barely start to engage without moving the car then when its go time slip it just a VERY VERY small amount and then let off. You can find a ton of vids of it. Also when I say slip it, its very breaf. roughly just enough to get your car to roll a couple inches, thats all


That sounds much better... thanks for the clarification, Steve! Maybe I should practice by setting the secondary rev limiter at something like 4k, just to get the hang of it first.

Sfkn2
10-03-2007, 08:48 AM
What's the use of having a secondary rev limiter?

earlyapex aka jack ass
10-03-2007, 12:36 PM
What's the use of having a secondary rev limiter?


It's a launch limiter. You can bounce off the limiter with the throttle at WOT. It will build a little amount of boost, you let the clutch out and hope you have nothing loose in the car or it will be in the back seat, hopefully it isn't your transfer case. :)

About 7-10psi depending on mods, boost control, etc:

http://www.norcalmotorsports.org/users/bryan/mods/EVO/tech/launch_limiter_boost_EBCS.JPG

earlyapex aka jack ass
10-03-2007, 12:37 PM
That sounds much better... thanks for the clarification, Steve! Maybe I should practice by setting the secondary rev limiter at something like 4k, just to get the hang of it first.


It will bog like a mother at 4k. Will probably be harder on your clutch then a 5k+ launch.

DoggDicker
10-03-2007, 12:44 PM
I think mine is 5k...I've never used it, but Andy does while it's strapped to the dyno...

DD





j/k...

WW_EVO9
10-03-2007, 12:50 PM
i use it all the time when im at Sac Raceway @ 5.5k, like what bryan said, have nothing loose in your car especially the cubby hole and hold on tight. and you'll have big smiles :D

turboevo8
10-03-2007, 01:41 PM
It will bog like a mother at 4k. Will probably be harder on your clutch then a 5k+ launch.


I haven't tried it on my EVO yet, but on my other car, I had to Monitor/data log what my load point and rpm is then tune for it. Sor at 4000 RPM at 140 KPA, you can retune for it to bog or not. Most likely it is too rich there or something.

earlyapex aka jack ass
10-03-2007, 01:48 PM
It's not a afr issue, it's that 4k isn't enough rpm to get our heavy AWD boat anchors moving on launch. ;) You want a little wheel spin to take some stress off the drivetrain as well.

It really depends on the hp/trq level of the car and the grip level. I couldn't get my evo to spin the tires at launch with a 5350rpm limiter and I was too lazy to switch it higher at the time. This was with 255/40/18 Azenis RT615. 1.79 60ft.

Matz
10-03-2007, 03:41 PM
Great info guys, thanks! I'll set it in the mid to high 5ks, then.

Evo9R
10-03-2007, 04:16 PM
i use to have the two step on my mr2 and i love it then and still love it now

UCB
10-04-2007, 05:26 PM
MIne is set at 5.5k too, I use it :lol:

Tire pressure also matters in terms of getting out o fthe box/not bogging. Its much much better to spin the tires than it is to bog and send a huge shock through the driveline

Sean/George both reccomend just dropping the clutch if its still stock, slipping the stock clutch=teh fail

Im at almost 18k now on my stocker, about 20 launches