Parts Usage Q's
General Project FAQ
- What am I getting myself into with a TurboFB project? Although
everyone's TurboFB project is different, there are a few commonalities.
As with many projects, your initial estimates of time and money will probably
be low. Small little engineering challenges creep into
the project along the way, and old, worn parts may need to be replaced as part
of the engine swap; not necessarily because you're installing a turbo.
You will likely see other components of your car that have failed, or you may
choose to replace and/or upgrade while the car is apart. All of those
changes cost money and take time. Here are the common issues that need
to be dealt with:
a) Exhaust- it will be custom made. There are no
off the shelf exhaust systems for a turbo 1st Gen.
b) Intercooler - although not necessary for low boost
applications, worth consideration. Piping will be custom, and may
require relocation of the battery. If you use the stock Turbo II intercooler
in the stock location, you should provide ducting through your hood.
c) EFI - if you know nothing about EFI systems, you'll
be learning a lot for this project! Unless you're using a blow-through
carb setup, your best option for fuel management is an EFI computer.
- How much power will I gain from turbocharging my 1st Gen Rx7? Power gains are entirely dependent on how the engine and turbo
built. Because most every turbocharged 1st Generation Rx7 project is
different, the total power gains are very different. Here is a rough
a) 12A with stock 12AT Turbo setup - 165 HP
b) 13B GSL-SE with Turbo II stock setup - 200-225 HP
c) 13B Turbo II transplant - 225 HP
d) 13B Turbo II modified EFI - 250-325 HP
e) 13B REW with modified EFI & aftermarket turbo - 250 - 450
- How much will it cost to turbocharge my 1st Gen Rx7? The cost of a turbocharging project is based on several factors.
The range is somewhere between free (you already own all the parts and can do
the labor yourself) and about $5,000.00. Here are some of the major cost factors:
a) Engine - a rebuilt engine core costs about $1800-$3500.
That's just for the core, no turbo, no EFI, no extras. On the low end of
the spectrum, a standard rebuilt non-ported, no frills engine is about $1800.
Un-rebuilt cores can be had for about $900. Full engine rebuild kits for
the do-it-yourselfer are about $600 from Mazda. That usually does not
include apex seals. On the high end of the spectrum, a fully race
prepared 13B turbo motor will be over $3000.
b) Turbo - stock Turbo II turbos are available fully rebuilt for
$800 - $1000. Upgraded aftermarket turbos range in price from $800 to
$4,500 dollars depending on the configuration. Used turbos can be found
on e-bay for $100 to $300. Be prepared to have a used turbo rebuilt if
it has had significant mileage since a rebuild, or since new. See
representative 2nd Generation turbos and upgrades.
c) Exhaust - no off the shelf systems exist. Expect to
pay $500-$1000 for a new custom exhaust. You can fabricate up an exhaust
with a Turbo II main cat and a 1st Gen exhaust parts relatively cheaply. An
exhaust shop can provide the needed flanges, tubing and experience. If
you have welding skills, you can easily fabricate your own exhaust system.
d) Fuel - a GSL-SE or Turbo II fuel pump can be used for an EFI
setup with stock or less-than-stock boost levels. Upgraded pumps are $250
e) EFI - cost for aftermarket fuel injection computers is
between $600 and $2500. The lower end systems will provide basic
functionality and a fully capable turbo EFI computer. However, the
higher end systems will allow greater tuning flexibility, and other features
such as datalogging, laptop computer real time monitoring, and boost control.
- How long will it take to install a turbo in my 1st Gen Rx7? Most people who've done turbo 1st Gen Rx7 (TurboFB) projects take between
3 and 8 months to complete their car. The factors that affect the project
a) large tool availability (welder, lift, engine stand, compressor,
b) time availability (can you work 7 days a week 5 hours a
day, or weekends only?)
c) financial resources (can you pay someone to do the job, or
will you do it yourself, do you have a buddy to help you out?)
d) parts availability (do you have 100% of what's necessary
to do the swap, or do you need to buy a large portion of your swapped parts?)
- Who can perform the work to turbocharge my 1st Gen Rx7? Generally, none of the major rotary engine rebuilders or rotary shops
offer a "TurboFB Package". A large part of the project is custom, and
since no kits are readily available, there is a significant amount of labor
involved. You might check with some specialty racing shops in your area
if you are unable to perform the work yourself. If you are familiar with
the mechanics of your Rx7, and are comfortable changing major components of
your car (transmission, exhaust, fuel pump/filter) you can probably tackle the
project on your own.
- Are there any kits available to install if I want to turbocharge my 1st
Gen Rx7? There were some turbo kits sold in the US and the UK in the mid 1980's.
Unfortunately, they are no longer sold off the shelf. If you run across
a used kit, it will most likely be a Cartech or Elford Turbo kit.
Because the kit will likely have been installed on a vehicle, unless you are able to
acquire the vehicle and kit at the same time, chances are high that you will
not receive a "bolt on" kit; something will undoubtedly be missing. You
may be able to find some used kits on
www.thepartstrader.com or www.rx7club.com
in the rotary used parts and engine modifications sections.
- Are there any kits available to install if I want to supercharge my 1st
Gen Rx7? As an alternative to turbocharging, Atkins Rotary of Tacoma, WA sells a
Camden Supercharger kit. While not cheap, this is one of the rare
opportunities to purchase a bolt in installable kit that will provide you with
6-9psi of boost in a carbureted or EFI configuration. The
supercharger is meant to bolt up to a Holley 4 barrel carburetor.
Alternatively, it may be possible to use a Holley ProJection fuel injection
adapter in lieu of the Holley carburetor. Mariah Motorsports also sells
the Nelson/Paxton supercharger for 2nd Generation Rx7's. Although this
is not a widely used configuration, it may be fairly straightforward to
install a 89-91 intake on a GSL-SE engine and use the Nelson/Paxton
supercharger. The base cost of these supercharger systems (without
any labor or installation) starts around $3,000. You should speak with
Jim at Mariah Motorsports about this option if you are seriously interested.
- Did Mazda ever sell a turbocharged 1st Gen Rx7? Yes, Mazda produced a 12A turbo Rx7 for the Japanese market only.
The 12A Turbo motor was also available in the Mazda Cosmo in the Japanese
market only. These motors are still available in very limited
quantities. See the vendors page for importers.
- Does it matter if I have a carbureted Rx7 or a fuel injected Rx7? The difference between carbureted and fuel injection in the Rx7 is very
significant to a turbo project. The preferred platform is an EFI system
(GSL-SE model in the U.S.). Although blow-through turbo installations
are still being performed, they don't offer the same versatility as a EFI
platform, and have a separate set of issues. This FAQ won't cover very
much detail on blow-through turbo setups, as they are rare among turbo FB
- What is the difference between supercharging my Rx7 and turbocharging my
Rx7? At a simple view, turbocharging has the benefit of using
(essentially) wasted energy in the form of exhaust to power the turbo. A
supercharger uses power from the engine (eccentric shaft pulley) to provide
power to the supercharger. In reality, the choices available to
turbocharge your engine are far greater than those for supercharging.
There are really only two systems available for supercharging (Camden and
Nelson/Paxton), and at least a dozen or more alternatives for a turbocharged
- What tools do I need to complete the project? The tools
that'll help you the most:
10, 12, 14, 17, 19, 22mm wrench
8, 10, 12, 14, 17, 19, 22mm sockets
Philips and slotted screwdriver
Mazda Shop Manual for your 1st Gen
Air compressor and wrench