Anyone running a clutch release solenoid/valve setup to help aid in slightly reducing the drivetrain shock load on launch? There are several variations, some are referred as "Magnus launch control". Just wanted to see thoughts from you other high HP guys that are still running the 6 speeds.

Thanks!

Jon

 

No one?

 

I looked into it and it seems like it would work in theory but I decided to go with a clutch designed for racing rather than adapt hydraulics to make a street clutch work. I'm currently installing a McLeod Soft-Loc.

 

A hydraulic controller can help some people cut better 60's but it all depends on the setup, and track prep. That said many of our street clutches have gone well into the 8's with out having to add a "Launch control" device.

Give us a shout if you have any questions.(817-750-2000)

 

The Magnus Launch Controller ends up as a compromise between reaction time and slipping long enough to be effective. Since it slows pedal travel from the point when you start to remove your foot from the pedal, there is a lag from the point of initial pedal release until the point where the clutch effectively starts to transfer power. If you are launching from a full tree where you can simply leave sooner to make up for the lag time, it will can very effective for reducing drivetrain shock. The downside is that the necessary compromise between reaction time and optimal slip time leaves quite a bit of ET on the table.

Going "well into the 8's" with a street clutch doesn't really tell you much about how efficient that clutch setup actually is. MPH can give you an idea how much power it took to get into the 8's, ET vs that MPH can give you an idea how efficiently that power was delivered.

There's just no way that a street clutch can be deliver optimum ET without adding some sort of slip controller. The problem is that it takes a lot of clamp to keep the clutch from slipping at max power, which happens to be too much clamp for an effective launch without either blowing the tires off or bogging the engine. Even worse for a turbo car that needs a lot of clamp to handle the power it makes in hi gear, but also needs to keep rpm up off the starting line to make boost.

The ClutchTamer is a clutch controller that gives you selective control over clutch pedal travel, only slowing down the last bit of pedal travel that affects how hard the clutch hits the drivetrain/tires. The driver still has full control over the part of clutch pedal travel that affects speed/quality of the shifts. The net effect on clutch wear is not what you might think, as it basically converts the clutch slip part of the pedal release cycle from hi clamp/short duration to less clamp/longer duration. Less clamp/longer duration of limited slip creates a much lower torque spike to be passed along to the input shaft, but net wear on the clutch ends up about the same until you start pushing things to the extreme. It makes dead hook launches possible so you won't need a hard hitting clutch to get the tires spinning, also the ability to dial out a dead hook bog right from the driver's seat. Along with adding dead hook launch capability, you also pick up the option of being able to run radials.

It's way more fun to drive a street/strip car thru the gate and make passes without the added hassle of swapping tires, it also eliminates the hassle of going under the car to adjust between "street" and "strip" settings like you would have to do with a typical race style slipper clutch.

Grant

 

Grant , can this tamer be used with the heavy LS7 clutch ?

 

Grant,

Is there a way to "turn off" the tamer after launch for quick shifts?

 

It can be used with most any clutch, as long as the clutch has excess capacity beyond what the engine requires. The ClutchTamer basically just uses mechanical/hydraulic means to add precision to the traditional "driver mod".

Grant

 

It's possible to effectively "turn off" the tamer for shifts, but if the tamer is properly adjusted the result will be slower ET.

Even for "clutchless shift" applications we find adding extreme amounts of ClutchTamer delay is an effective way to add a decaying amount of clutch slip after each successive shift, even though the pedal was not activated for the shifts. It shows up on the timeslips, here's a comparison of two nearly identical back-to-back runs with zero wheelspin during launch. The blue pass has less clutch delay and bogs to 4622 rpm at .728 sec into the run. The only difference with the yellow pass is an additional 1/2 turn of delay added to the ClutchTamer adjustment. The added slip time raised the bog rpm to 5202 which increased hp output, and it reached the top of 1st gear 0.089 sec quicker. The added slip time also slightly reduced the wheelspeed spikes after the shifts, which improved net power overall to the point where the yellow pass reached the same driveshaft rpm 0.502 seconds quicker at the top of high gear...



Notice that the car gains rpm at exactly the same rates in each gear on both passes. The improvements come on the parts of the graph where the engine is losing rpm, which are basically controlled by the clutch. The shifts may look slower at first glance, but the car actually gained speed at a faster rate.

Here's a graph with just the engine/driveshaft ratio displayed, so you can better see the differences in clutch slip time...




As you can see, it didn't take much added slip time to make a huge difference in ET.

Grant

 

Thanks.