Manually cranking a freshly built 12A peripheral port engine. The engine is built with 3 window bearings, is doweled and has a shimmed oil pressure regulator. Ultimately it will run EFI and be turbocharged. Plugs are installed (listen to those pops!)
Part 12: 13B Rotary Engine Rebuild - My 76 Mazda RX-5 Cosmo Restoration
Just as I promised last episode, it is finally time to build the engine!
Part 12 of my RX-5 Cosmo restoration covers the entire process of building
the 6 port 13B Mazda rotary engine. While this engine is a hybrid of GSL-SE
RX-7 and Cosmo parts, the process is the same for any rotary from a 12A to
a 13B NA, 13B turbo, 13B-REW or any
other variant of the 13B. This video shows the whole process of the engine
build, starting from measuring the rotors and covering everything else
including clearancing the side seals, assembling the rotors, complete
assembly the short block, setting the eccentric shaft end play and
installing the front cover and everything underneath it. It's probably the
most complete engine build video outside of what you can buy from the
vendors, and as such, is an hour long. After this one, I'm going back to
videos under 20 minutes. But for now, grab a beverage of your choice, sit
back, and enjoy.
GT4088R Turbo on Bridgeported RX-7 Rev, Spool and Shutdown
Starting, revving and shutting down my aux bridge high compression 6 port
turbo RX-7 looking into the mouth of the
GT4088R ball bearing turbo. Notice the
easy spool and count how many seconds it takes the turbo to stop spinning after the car is shut down.
Talk about turbo response! 10 PSI by
3000 RPM at less then 70% throttle.
The entire build process of this car can be found at
Part 38: Fuel Tank Restoration With POR-15 Sealing Kit - My 76 Mazda RX-5 Cosmo Restoration
I guarantee that aside from part 38 of my '76 Cosmo Restoration, you will
not find more footage on YouTube of someone shaking a fuel tank. You have
my word that this is the most tank shaking coverage you will see in any
video. Why so much tank agitation? Because in this episode I clean and seal
the 40 year old fuel tank using the POR-15 fuel tank restoration kit. This
is something which several have requested be shown so I figured as sealing
was a common issue for old fuel tanks, why not dedicate an episode to the
task. I begin by recycling some of the cleaning footage from the past two
episodes then move right into the process of the POR-15 kit. First any
remaining debris is "chained out" by using the old trick of rattling some
chains around inside the tank. Then the tank is cleaned with the supplied
cleaner, etched with MetalPrep and finally coated with the sealer. The end
result is a tank looking better inside than the day it came the assembly
line which will not be subject to future corrosion. To go with the spiffy
clean interior, the outside is given a coat of POR-15 rust preventative
paint as well.
And did I mention this is my first episode in HD?!
Part 7: My 76 Mazda RX-5 Cosmo Restoration - Intake and Exhaust Porting
Has it been nearly a month since my last episode? Wow, time does indeed
fly. I've been quite busy preparing to build the engine. So in part 7, I
cover the intake and Exhaust porting.
The engine is being built with GSL-SE 6 port plates and the Cosmo rotor
housings as the basis for a 6 port turbo
setup. This port job is fairly conservative, only opening up the primary
ports a little and bringing the Exhaust ports close to 2nd gen RX-7 specs. The
goal is to maintain fuel economy, low and midrange torque, and idle
quality. This episode covers everything involved in porting including:
marking out the new ports, grinding the port shape, smoothing the bowls,
smoothing port to runner transitions, smoothing the runners, grinding and
blending the Exhaust ports.
Part 37: Carbureted Fuel Tank Conversion to In Tank EFI Pump - My 76 Mazda RX-5 Cosmo Restoration
Part 37 of my '76 Mazda Cosmo restoration focuses on one specific task in
great detail. That task is converting the old carburetor feeding fuel tank
to one which can satisfy the high pressure needs of fuel injection. The
approach I take is to modify the tank to accept an in tank fuel pump via
custom bracket, emulating the approach used on modern vehicles. My
inspiration for the setup was the Aeromotive Phantom EFI tank conversion
kit. However as the Aeromotive unit wouldn't fit in the space I had
available, I chose to fabricate my own version. Additionally, I continue
the task of cleaning the fuel tank as well as finish off by wiring up the
Loudest Mazda RX7 exhaust sounds in the world!
Loudest Mazda RX7 Exhaust sounds in
2002 Mazda RX7 FD3S Fujitsubo catback Exhaust
1985 FB Rx7 Chevy 350 (https://www.youtube.com/watch?v=cm08uKhqF9w) by
1989 Mazda RX-7 turbo II
Mazda RX7 (https://www.youtube.com/watch?v=DHQKrMP1r-M) by
Mazda rx7 fc3s s4 racing beat headers presilencer apexi Exhaust
Picture (thumbnail): by
How to rebuild a Rotary Bridge Port engine ~ fullBOOST tech files
FullBoost Tech Files, Ep 1 ~ Rebuild
and Bridgeport of a 13B rotary engine @ Mr Parts.
We have started with a stripped down 1984 Mazda RX7 13BT engine, and will
run through the steps involved in bridge porting the engine, then assembly,
to the start up in its new home, a 1972 Mazda 808 (RX3). [
Get your track gear!
Follow us on social media @
SCREAMING 20B rotary engine dyno ~ JPC
Centreline Suspension's 20B PP rotary engine from their Mazda RX-7 Sports
Sedan circuit racer on the Dyno at JPC.
Part 35: Water To Air Intercooler Installation, Part 2 - My 76 Mazda RX-5 Cosmo Restoration
In the last episode of my '76 Mazda Cosmo restoration, the basic components
of the water to air Intercooler system were laid out along
with the considerable amount of fabrication needed to build the throttle
body inlet, Intercooler
piping and water tank. As well as mount the heat exchanger and BOV. In part
35, we finish up the water to air Intercooler installation by taking care
of mounting the pump, plumbing all the water lines and wiring up the
system. Additionally support brackets are built to support the piping. Lack
of space meant I had to get creative with pump position after accidentally
creating a clearance issue with the water fittings. However once mounted I
was very happy with pump position and the plumbing was straightforward.
Included in this episode: Cutting/grinding/drilling aluminium, making
aluminium brackets, assembling AN house and fittings, wiring relay to spare
Megasquirt output, adding temperature sensor to Megasquirt analog input,
plumbing air to water Intercooler with tank and pump, TIG