HitMaster In-Line Hydraulic 2-Stage Clutch Hit Control System

Every manual transmission car has its own unique "sweet spot" in the clutch pedal's release travel. That's the spot in pedal travel where the clutch hits just right and slips a perfect amount to efficiently launch the car. Below that sweet spot the clutch doesn't grab hard enough, allowing it to slip too much which may damage the clutch. Above that sweet spot the clutch grabs too quickly, causing it to either bog the engine, spin the tires, or break parts. But in between those two extremes, there lays a perfect "sweet spot" level of slippage that doesn't either damage the clutch or bog the engine.

Our patent pending Hitmaster valve is unique in that it is a positive fluid displacement throw-out bearing positioning device. Regardless of rpm induced clutch feedback pressure or fluid temp, the volume of fluid return flow is not affected. As a result, the throw-out bearing hits the same target 1st stage throw-out bearing position every time, and without any reaction time killing Magnus style delay. Works on all hydraulically actuated clutches- diaphragm, B&B, Long, single, dual or even triple disc, even improves top shelf adjustable clutches by making them more adjustable!
...If you are currently tuning an adjustable centrifugal assist clutch, you don't know what you are missing! It's a fact of stick shift drag racing life that you need more clutch slip during launch than you need after the gear changes. To achieve that goal using centrifugal assist, launch rpm must be lower than shift rpm. A Hitmaster controlled launch eliminates the headaches that come with the static pressure vs centrifugal assist balancing act, making it easier to dial in your launch and efficiently harness the performance benefits of higher launch rpm. For more info and an explanation of how this is even possible, CLICK HERE.
...The Hitmaster is more consistent than PWM clutch control devices- pulse width modulation based clutch control devices rely on timed fluid flow to position the throw-out bearing during launch. Basically, fluid flow volume is determined by controlling how long a valve stays open. Problem is centrifugal feedback forces from the clutch fingers pushing against the throw-out bearing change with launch rpm, which in-turn affects fluid pressure within the clutch release system. Fluid viscosity also changes with fluid temperature. Both of these variables affect PWM timing requirements when attempting to hit a consistent throw-out bearing position during launch.
In contrast to the timer function in a PMW controlled system, the Hitmaster system's timer setting has no effect at all on determining throw-out bearing position during launch. It only controls the much less critical function of how long the clutch stays in 1st stage mode.
...If you already have a Magnus style variable restriction system in place- it can be upgraded by replacing its needle style flow control valve with our Hitmaster valve. The Hitmaster valve is easy to mount within reach of the strapped in driver, and you can also use your existing Magnus solenoid. Upgrading to the Hitmaster valve eliminates the Magnus requirement of "pre-loading" the drivetrain with the clutch before launch, which in-turn eliminates red-lite fouls due to an overheated clutch pulling you thru the beams prematurely. It makes you completely immune to having your clutch burnt down by a late staging opponent, there are RWD, FWD, and AWD drag racers at the very top of the game that have switched to the Hitmaster system.

Get The Perfect Radial Friendly Dead-Hook Launch With Our NEW "HitMaster" Clutch Hit Control System !

Our HitMaster 2 stage system makes it easy to consistently walk that fine line between bogging and spinning, even with a radial! Our exclusive 1st stage of INSTANT CONTROLLED HIT allows the clutch slip just long enough to prevent the bog, then the 2nd stage takes over to make sure the clutch doesn't slip any longer than it needs to! No more slow reaction times, no more inconsistency, no more breaking stuff. In the end you get an efficient controlled dead hook launch that's also radial friendly and doesn't break parts!

At the heart of our 2 stage system is our "patent pending" HitMaster 1st stage control valve (pictured above). This innovative valve gives you the unique ability to dial in exactly how hard the 1st stage of your clutch initially hits, while also allowing that controlled hit to happen the instant you release the clutch pedal. Our exclusive HitMaster valve completely eliminates the reaction time delay that plagues some other hydraulic launch control systems. With simple hose connections, it's easy to adapt our system to almost any car that uses a hydraulic clutch release system. Easily hidden as well, this system is also ideal for owners of modern musclecars that want an instant hassle free and efficient launch that eliminates wheel-hop while putting far less stress on those fragile oem drivetrain parts!

HitMaster system components come with female 1/8" npt fluid ports. From there, it's pretty easy to plumb the system with just about any style of fittings/hose you might choose. The typical hydraulic clutch release system operates on less than 500psi and although the system could be plumbed with hard line, we prefer using either nylon tubing or hose as the added flexibility can make it easier to bleed the system.

When plumbing the Hitmaster system with AN style fittings, be sure to use PTFE lined hoses. Imports generally use smaller ~5/8" master bores and are fine using -3 fittings/hoses, but domestic applications typically use 7/8" and larger masters that are better suited to using -4 fittings/hoses. AN fittings are basically the same as JIC as far as sealing geometry, so it's pretty common to see mixing/matching of the two in an automotive application. JIC spec fittings and hose ends are typically made of steel and are generally less expensive than the typical anodized aluminum AN counterpart. JIC fittings can be found along with PTFE lined hoses at suppliers such as Summit Racing or local hydraulic supply shops.

Basic System Configuration...
On the right, you will see a plumbing schematic of our preferred basic system configuration. Although we do have the ability to build the HitMaster valve as a stand alone clutch hit control system for special circumstances, we generally prefer to add circuits externally as this gives more flexibility to add features later as vehicle performance evolves.

The external 2nd stage transition valve and 1st to 2nd stage transition timer are very important to the system overall, as the stepped 1st to 2nd stage transition they create makes it possible for the HitMaster to hit even deeper within the sweet spot zone than was possible with the original ClutchTamer. They also make full clutch clamp pressure available much sooner than the original ClutchTamer design, which can be important for getting the most out of turbo or nitrous applications!

HitMaster 1st stage control valve adjustment...
The HitMaster valve uses a simple dial type adjustment and should be located within easy reach of the driver's seat. This allows the driver to dial in more/less "initial hit" of the clutch without even unbuckling his belts! This can be a great advantage, as it allows the driver to make a last minute assessment of track conditions and then adjust clutch hit as needed before staging.

HitMaster Valve Adjustment...
Rotate HitMaster dial clockwise = softer hit / less rpm loss
Rotate HitMaster dial counter-clockwise = harder hit / more rpm loss

For best ET, you generally want to stage at about 2000rpm above your engine's torque peak. Basically, that means keep adding counter-clockwise turns to the HitMaster valve adjustment with each run, until either the tires start spinning or the 60's stop improving, then return to the previous setting.

On the other hand if the tires spin instantly on the hit, keep adding clockwise turns to the HitMaster valve adjustment with each run, until either the tires stop spinning or the 60's stop improving.

1st to 2nd Stage Transition Timer Adjustment...
Start with an initial transition timer setting of about 0.8 sec. If the tires initially stick for a few feet but then start spinning before 15'-20' into the run, add 0.10 sec to the timer setting with each run until the tires quit spinning or the 60's stop improving.

It's not uncommon for our street/strip customers to find up to a 0.8 sec improvement in 1/4mi ET, along with much improved consistency.

HitMaster System Install & Tuning Guide...
Here's a link to our install & tuning guide in a PDF format HitMaster Install & Tuning Guide PDF.

Here's an article on our original ClutchTamer device from the April 2019 Issue of NMCA/NMRA's Fastest Street Car Magazine!!!

"CLUTCHTAMER HELPS MANUAL-TRANS MACHINES FLY" is how Fastest Street Car Magazine describes it's April Top Tech story.
In a 5 page feature article that starts on page 126, they also review some of the racers that are using it.
CLICK HERE to check it out!

Alternative System Configurations...
Adding an adjustable bleed valve in parallel to the HitMaster valve basically makes the system act exactly like our original ClutchTamer during launch.
Adding dual timers gives you the ability to have separately adjustable 1st to 2nd stage transition points for launch and shifts.

Pictured below on the left is the 2nd Stage Transition Valve which we mounted directly onto our Shop Mule's clutch master cylinder using a steel hydraulic "T" fitting. The upper line in the pic on the right side of the solenoid goes to the car's hydraulic throwout bearing. The two lower lines on the left pass thru the car's firewall on their way to the floor mounted HitMaster valve.


Pictured above on the right is the floor mounted location we chose for our Shop Mules HitMaster valve. Just under the front of the seat, you can also see the aluminum panel we made for experimenting with using separate transition timers for the launch and shifts.
….The timer on the left of the car is for launch, it is triggered by releasing of the line-loc switch.
….The timer on the right is for the shifts, it is triggered by a switch that's actuated by the clutch pedal.


HitMaster Clutch Hit Control Valve (1/8npt fluid ports).........…...…….…$299.

2nd Stage Transition Valve (1/8npt ports, appx 2.25a @ 14v)..........…...$99.

1st to 2nd Stage Transition Timer (12v)...….............................................$39.

Priority Mail Shipping to a destination within the USA.......................add $18.


......Option 1- Clamp Style Black Anodized Mounting Bracket..................$39.

......Option 2- Shifter Mounted "Launch" Trigger Button............................$19.

......Option 3- Hydraulic in-line "Shift" Trigger Switch (1/8"npt).................$29.

......Option 4- LED 1st Stage Indicator Light...............................................$9.

......Option 5- Steel -4 Fitting Upgrade...…................................................$29.

......Option 6- Black Aluminum -3 or -4 Fitting Upgrade...…......................$59.

......Option 7- Control Cylinder for Mechanical Linkage Applications.......$199.


Customer Q&A...

QUESTION- What makes the Hitmaster better than the other manual transmission "launch controllers" on the market?

ANSWER- Here's what TOB pressure release curves look like when using Magnus/MAP/Clutchmasters/Tilton style simple hydraulic restriction to control the clutch's engagement speed...


The sweet spot for the clutch is that zone between too much bogging and too much spinning. For this hypothetical example, let's say the car's sweet spot zone for a launch "hit" is somewhere between 200-125 psi at the TOB. The graph above shows it takes 0.686 sec from clutch pedal release for this example's TOB to reach 200psi.

The common fix for that launch delay is to "pre-load" the clutch/drivetrain with the clutch pedal. Let's say you can pre-load the TOB down to 300psi before the car pushes thru the beams. Even with that 300psi pre-load prior to launch, delay time from 300psi to the beginning of the 200-125psi sweet spot zone is still .362sec. That delay makes the clutch slow to hit the sweet spot, but then it only spends 0.334 in that sweet spot zone before dropping below 125psi. Long enough to stick the tires, but not long enough to prevent a mild engine bog.

If you increase the restriction size to reduce the delay time, pressure at the TOB will drop past the sweet spot zone too quickly, causing the car to slow down due to too much tire spin or severe engine bog. Basically the size of the hydraulic restriction becomes a compromise between launch delay and bogging/spinning. The hit ends up both lazy and not lasting long enough, but it's still far more consistent than trying to ride the sweet spot zone with your foot.

Here's a graph of our Hitmaster's typical TOB pressure release curve...

The Hitmaster responds as quickly as you can remove your foot from the clutch pedal, with no added delay. It's adjustable 1st stage hits the lower limit of the sweet spot zone almost instantly for a firm/crisp hit that's just short of spinning the tires, and then you have control over how long the clutch stays there before the 2nd stage kicks in to lock the clutch up. You can't even come close to this release curve shape with the Magnus/MAP/Clutchmasters/Tilton units. The Hitmaster system is basically like having two clutches in one- 1st stage dialed in for the best launch, 2nd stage for holding all the power you can make.

We recently had a customer install the Hitmaster system on his C6 Corvette, he reported five 1.43 60's in a row during his first track session with the system installed.

QUESTION- Can I turn the Hitmaster off for street driving?

ANSWER- If you prefer, you could disable the system by installing a simple toggle switch in series with the trigger wire. That said, there really is no need to turn the system off for casual driving, as the "default" position of the transition valve provides a direct fluid path between the clutch master cyl and the slave. Bottom line is during casual driving, normal clutch operation is not affected in any way unless the launch trigger switch is activated.

QUESTION- Do I engage the line-lock button when I stage, then just release the line-lock button and side step the clutch to launch? If everything is triggered off the release of the line-lock button, how do I use the line-lock for burnouts?

ANSWER-Yep, just release the launch button and side step the clutch to launch the car. Although the system doesn't have to be triggered off the line-lock button, we do suggest it as then a single button can both release the line-lock and also trigger the Hitmaster's transition timer. If you do not have a line-lock or line-lock button, as an alternative you could use one of our shifter mounted switches to trigger the system.

If you want to turn the system off for the burnout, a simple switch can make that happen. Radials usually don't need much burnout, usually just a quick 1st gear hit to clean the tires off. Typically you don't need to turn the system off for a 1st gear burnout with wet tires. But if you need to really heat up a set of bias slicks with a 2nd or 3rd gear burnout, it would be best to temporarily turn the system off for the burnout only. For that we suggest a normally "on" momentary push button switch to interrupt the system's trigger signal, hold the button down to de-activate the system for the burnout only. Using a momentary switch to de-activate the system instead of a simple two position switch eliminates the possibility of forgetting to re-arm the system after the burnout.

QUESTION- Can I use the Hitmaster system with a SoftLoc style clutch?

ANSWER-Yes, you can. The main benefit will be that you will no longer have to compromise your launch rpm to keep your clutch from slipping in high gear.

Here's my suggestion for an easier way to tune a SoftLok style adjustable clutch-
...1- remove the weights from the levers.
...2- crank up the base pressure until the clutch can hold high gear.
...3- install the Hitmaster system to control the clutch hit.
...4- raise launch rpm to match your shift rpm.
...5- using the Hitmaster valve's adjustment knob, adjust the hit until the clutch pulls the engine down from launch rpm to torque peak rpm.

Removing the weights from the levers will reduce flex in the clutch assy, you won't need as much throwout bearing gap.

You might be able to calculate your current base/weights/rpm to determine how much clamp "holding high gear" requires, that would give you a ballpark starting point for cranking up the base. Remember to account for lever rpm, even without extra weights those bare levers still add clamp as the rpm goes up.

Installing the Hitmaster system allows you to adjust the clutch hit independently, without affecting the clutch's ability to hold high gear.

Raising launch rpm to be the same as your shift rpm will make more energy available to launch the car. Instead of the rotating assy absorbing energy during launch, it will be adding net energy to the input shaft. Raising launch rpm from 5500 to 7000 will make 62% more energy available, also more closely aligns your clutch tune needs for launch vs shifts.

Adding the Hitmaster system transforms a clutch hit that would otherwise be too intense, into a hit that's less intense but longer lasting. It basically conditions the added energy of a higher rpm launch to a longer lasting level that the chassis can process.

Our alternative adjustable clutch tuning method works so well that very competitive racers are now using it on the national level to control the hit of their very expensive adjustable clutches. Dialing in the hit of the clutch from the driver's seat and winning races with a stick shift on radials is now a reality!

QUESTION- Can the Hitmaster be used on a nitrous or boosted car?

ANSWER-That's where the Hitmaster really shines. It can hit deeper in the clutch's sweet spot while still giving you all the slip that you need for launch, and then quickly transition to full clutch clamp pressure to hold the torque of nitrous/boost as soon as the car will take it. That 2nd stage transition point to full clutch clamp pressure is controlled by a simple timer, easy to adjust in 0.01 sec increments.

For nitrous, we generally suggest delaying the nitrous hit until the clutch is almost locked up. If you look at data graphs very long, you will notice that the car actually accelerates at a faster rate while the clutch is pulling the engine down. That's basically due to an inertia boost that you get while the rotating assy is losing some of it's stored energy. Using a nitrous delay allows the nitrous to come in on the heels of that inertia boost instead of adding to it, which in-turn makes overall power delivery much smoother for radials and no-prep surfaces.

QUESTION- How your are installing the two timers to separately control the shifts?

ANSWER- Here's the configuration we suggest for using two timers to make the Hitmaster system also active after clutch assisted shifts-
...Launch timer is triggered off the release of the line-lock button.
...Shift timer is triggered off a pressure switch installed between the clutch master and Hitmaster valve.
Both timers are wired in parallel to the same transition valve. Since the launch timer is set to a longer delay than the shift timer, it's the launch timer that ends up controlling the clutch's transition point after launch. But then since you don't use the line-lock button on the shifts, the shorter duration shift timer ends up being the one that controls the Hitmaster's transition point after the shifts.

QUESTION- I purchased 2 Hitmaster systems a little while back, and have recently installed one into my S550 Mustang. I did not install it myself, a company installed it and I believe they were in contact with you a couple of months ago for advice.

The system is working, although I have yet to test it. I wanted to confirm with you that it is installed and working correctly, this is what is happening when tested with engine off. When I release the clutch, the pedal stops at the desired location adjusted by me. At this point the timer cuts in, and when it times out the pedal quickly fully engages. My concern is there seems to be no transition between the 1st and 2nd stage. The pedal stops at the first point, stays in that exact position for the amount of time put into timer, then fully engages.

I have one of your original ClutchTamers (mechanical version) on another car that I have been racing for over a year… I absolutely love it, I have done 56 passes with zero breakages and have become extremely consistent- 10.78 10.75 10.80 et’s, and I'm enjoying bracket racing again. It's 'Tamer has a transition between the two stages where the pedal slows right down through the sweet spot…. The Hitmaster installed on my S550 Mustang does not, it seems very harsh compared to the mechanical version…. I just wanted your advice before testing it to see if this has been installed incorrectly.

ANSWER- It sounds like the Hitmaster system installed on your S550 Mustang is operating correctly. The Hitmaster's 1st stage is only supposed to be active until vehicle speed gets a chance to sync up with engine rpm, which generally occurs about 15'-20' out from the starting line. After that MPH/RPM sync point the clutch is no longer slipping, so the Hitmaster's sudden transition from 1st Stage to full clutch clamp pressure has no affect on traction, adds no shock to the drivetrain, and minimizes wear on the clutch by ensuring the clutch isn't slipping any longer than it needs to.

Basically the clutch needs to stay within your sweet spot zone until the sync point.
With the ClutchTamer, the clutch must hit above the lower limit of your sweet spot zone in order to stay above that lower limit for that first 15'-20'. This is due to the original 'Tamer's gradual gain of clutch clamp pressure after it's hit point.
With the HitMaster, you can hit right at the lower limit of your sweet spot and still not blow thru it before the sync point.

Generally the closer the clutch can hit to your sweet spot zone's lower limit without blowing thru it before the MPH/RPM sync point, the quicker and more efficient the launch will be. Because the HitMaster has the ability to hit deeper within the sweet spot zone, it can typically 60' a little better than our original ClutchTamer. The HitMaster can also get to full clutch clamp pressure quicker after the sync point, making it a better choice for handling the full torque of a power adder.