HCF Graziano Sequential conversion kit

HCF - John

Gearbox / Brake Systems
HCF is pleased to announce a kit that automates the operation of the Graziano L140 transaxle, allowing for a clutch-free sequential shifting operation. The HCF kit was designed by the same firm who designed the automated gearbox systems for Volkswagen Audi Group in the Gallardo and R8. The system is bespoke, but adapted from the gearbox control system in the successful Dallara Stradale.

The kit will consist of the following items, as depicted below:

1) Hydraulic main unit with solenoids, pressure sensor, filter and accumulator
2) Two instrumented actuators for gear selection and engagement
3) Electric oil pump
4) Hose kit and nipples
5) Wiring harness
6) Electronic Gearbox controller

Graziano L140 AMT System.jpg

Like popular racing transaxles available, this conversion allows for the driver’s hands to remain on the steering wheel and for shifts to take place faster than with a conventional H pattern shifting motion. Operated by paddle shifters or a strain gauge, shifts are accomplished in 186ms as depicted on the chart below:


The primary benefits of HCF’s sequential shift conversion versus currently available alternatives are:
  • Expense: roughly half the cost of a quality racing sequential gearbox
  • Longevity: avoid expensive, frequent rebuilds of a racing gearbox
  • Replacements: readily available, mass produced gearbox replacement parts
  • Configuration: retain helical cut gears for strength and noise suppression
  • Strength: higher proven torque capacity in the L140 versus racing sequentials
  • Safety: making use of the L140s speed sensor, over-rev conditions can be prevented

The system has been through extensive testing and has a service life north of 50k kms with no maintenance required. The system will retain the OEM release bearing used in the L140 and will be optimized to work with HCF’s Kevlar and Ceramic clutch packages. Wheel speed sensors are incorporated into the programming to maximize safety and minimize the potential for damage to the engine and gearbox from a manual over-rev situation.

Gearbox controller and actuators will be provided fully programmed. Final install into the car will require inputs for Engine RPM, gas pedal position, a brake signal and an output to cut ignition.

Pricing for the kit is estimated at $10k and assumes there are 10 customers committed to it. We have been discussing the potential for this kit with several existing customers and have 3 commitments so far. Compared to alternatives, we believe this conversion represents a strong value to owners desiring a sequential gearbox without its many drawbacks.

If there are any questions, please feel free to discuss in this thread or reach out to us directly at [email protected].

Thank you,

Ken Roberts

Is this system similar to the R-Tronic Audi system? Is it made by Magnetti Marrelli? If so is it improved in any way over the poorly reviewed OEM system?

HCF - John

Gearbox / Brake Systems
Similar in that they are both hydraulically-actuated systems that automate the gearbox. The Magnetti avenue is internal to the gearbox and was the first one I explored. Unfortunately Magnetti is prohibited by their contact with VAG from selling those components to 3rd parties.

The OEM system had to be programmed to satisfy a large number of different users with different end uses in mind which may have contributed to the reviews you're referencing.

For this system, I'd guide that the intended end use is a track setting and the programming will be oriented for that purpose. Conceptually it's a Gen 2 to the early Ferrari F1 system in the F355 - great when driving the car aggressively but a little clunky doddling along in traffic. This will incorporate some safety measures and the programming should be a little smoother versus those earlier systems.

It goes without saying, they will be substantially more drivable than the racing sequential gearboxes.

Joel K

Exciting news John,

I’ve had a chance to drive the Ferrarri Modena with the F1 gearbox on the street and have to say it was alot of fun. It will be interesting to undertand how your system will drive when mated up to at GM power plant.

HCF - John

Gearbox / Brake Systems
Thanks Mario - sent you a PM back.

Hi Joel - it's actually the GM products (in particular the GM ECU and electronic throttle) the factory has the most experience with. That's what all the testing was based upon. I expect it to work quite well!

HCF - John

Gearbox / Brake Systems
For those of you who have inquired, these are the wheel-mounted paddles we anticipate supplying with the kit. They are an OE production unit of high quality.

volante 1.jpg

volante 2.jpg

Dallara Stradale wheel with paddles.jpg

For those preferring a strain gauge / bump stick configuration, that can be accommodated on a one-off basis as well.

HCF - John

Gearbox / Brake Systems
Thanks Cam!

Since there are so many different steering wheels owners use, I expect we’ll see some variation in how the paddles attach.

Assuming there’s a quick release hub, an ideal spot would be to mount with a bracket making use of one of the existing bolts running through the wheel.
Hey guys,

I am a SLC Aero owner and found HCF and this paddle conversion when I was looking for drop gears for the Graziano transaxle. This conversion seems to fit exactly with what I wanted to do with my car at a significantly reduced cost than the alternative of buying a dedicated racing transaxle like the Albins ST6M. I look forward to seeing this conversion happen in my car and think it will work well in both street and racing applications, racing in my case.

HCF - John

Gearbox / Brake Systems
We've taken deposits from several owners and are proceeding with the conversion kit.
There's a window left to add to the initial order for anyone interested. Please reach out to us at [email protected] if that's the case.

The cost of the kit will increase to $12,000 for individual orders after this initial run.

Top Gear did a segment on the Dallara recently, showing the system in action -

More with the Stigs hot lap -

HCF - John

Gearbox / Brake Systems
Video of the final product, tested and programmed, below! My hope is we'll see customer installs sometime in Q1 and the kit in widespread use soon thereafter.

Anticipating varied end uses, we paired the base tune for the kit to 4 different clutches:

- HCF Kevlar clutch/flywheel - for street cars making up to 1000 lb-ft and able to properly break the clutch in
- HCF Ceramic clutch/flywheel - for street/track cars making up to 1200 lb-ft; little break in required
- HCF Ceramic clutch/flywheel with a heavy duty diaphragm - for street/track cars making up to 1500 lb-ft; little break in required
- Tilton 4 Plate Carbon clutch/ HCF Flywheel - to support a 3,000 hp Graziano build we have underway for a customer

For each application there are several items the TCU is custom tuned for based on the particulars of the engine, ratios chosen, tire sizing and engine controller.



Lifetime Supporter
The HCF solution coverts a manual H-pattern to a paddle shift. It operates the clutch and mimicks the shifting motions that a human was intended to make.

The ST6-M is sequential so all that’s needed is linear forward or rearward motion... nothing could be simpler. This can be done manually via a lever or via paddle shifters driving a
Linear motion device. Most of the linear shifters that I’ve seen are pneumatic. The challenge is that the ST6-M is a dog box so you don’t use the clutch other than going into first or reverse which means that you need to be really good a rev matching when downshifting.

In addition you need to aggressively shift a dog box. If you drive it like a Graz or any other synchro box your going to damage the dogs. The best way to get lightning fast, perfectly rev matched shifts is to use an ECU that’s tightly integrated with engine management.

My build has an ST6-M, MoTeC M150 and Shoftec