Welcome to Downs Engineering
We are now in our 35th year as a
California company and 55 years
in the racing industry. We have
expanded our Hayabusa product
line in order to better serve our
customers. We are a full service
shop and are available to do
research and development
projects, from engine and oil
systems to complete car builds.
We have developed race winning
products and systems for the
Hayabusa engine for the past 18
Suzuki Hayabusa Engine
Undergoing Testing On Our
making you go fast is what we do best!
Hayabusa Specialty Parts
Setting up a custom design
Turbo Engine on the Dyno
Our Wet Sump and Dry Sump Oil   
Systems are the best Hayabusa    
Systems on the market today
Parts and supplies for all types of Motorsports.
Sand Rails, Kit Cars, Race Cars, Motorcycles, Track Cars,
Street Cars
Contact Mike Downs
Downs Engineering
19564 Eighth St East
Sonoma CA 95476
phone: 707 938 1011
email: mdowns@downsengineering.com

Property of Downs Engineering. All
rights reserved.
Having problems with your Busa? Low oil
pressure? Oil starvation in corners?
Connecting rod failures?  
Click here for
solutions to these and other problems
inherent in the Hayabusa engine.

We will rebuild your Hayabusa engine using new OEM Main and Rod bearings. The
rebuild also includes New Piston Rings, New Oil Pump, and Cam Chain, as well as a
complete competition valve job. We thoroughly inspect the gearbox and shift forks,
along with the condition of the clutch discs and clutch basket. We run-in the completed
engine on our engine dyno. After run-in we make power runs on our in-house
dynamometer to insure proper running.

If you would like to upgrade your pre 2008 engine to current power and torque levels
we can install the 2mm stroked 2008-2011 1340cc crankshaft and replacement
exhaust cam.

Get ready now for the 2019 season. Racing starts again soon.
Click here for details
We are now dealers for Wossner
connecting rods, currently the
strongest Hayabusa connecting rod
available.  Limited time introductory
offer:  $859.00 per set.  Order your
set today.
  The "best bang for your buck" parts to  improve
the performance and reliability of your Hayabusa
High Volume Oil Pump Gear                   $115.00
High Pressure Oil Pump Relief Valve      $79.95
HD Cam Chain                                        $150.00
HD Clutch Springs                                   $39.00
Offset Timing Key                                    $89.95      
Race Car Design and
Race Car Restoration
For a limited time, 10% off D/E Hayabusa Wiring Harness. Our modified harness
removes all the unwanted bulk and mystery of your stock harness. Attach an
ignition switch, starter button, and you're ready to go.
Lotus 35 before and after restoration
200 MPH Mustang designed and built
by Downs Engineering
Need help getting your Formula Ford ready for the
50-year anniversary celebration at Road America this

From complete restoration to inspection and set up, we can help.  Call
Mike today to schedule your time in the shop so you can be ready for the
September 11-15, 2019, event.