improvements will I see?
The first TBI conversion was been done to a stock 1971 Triumph TR6. Driving impressions are excellent with much improved
drivability and a noticeable performance gain. Actual horsepower gain is not really known at this time although testing with a G-Tech accelerometer showed delivered (rear wheel) horsepower of ninety seven. From what I've seen the average TR6 dynos with rear wheel horsepower of 60 to 75! There have only been a handful of G-Tech runs made and this is the best of the bunch so these figures may not be accurate. Considering drivetrain inefficiencies of 20% a reasonable flywheel figure is 121BHP. Originally the carbureted car was rated at 106BHP.
UPDATE May 2009: Here we are five years later and conversion kits
have been shipped worldwide covering everything from Triumphs to Land
Rovers to Datsun 240Z's.
Will my fuel economy be impacted?
The supplied chip is programmed for fuel economy over 45 MPH. TR6 users with
overdrive or 5 speed conversions are getting in excess of 30 MPG on the highway while those without
overdrive are averaging about 28 MPH. Around town mileage is in the low 20's.
How dependable is this upgrade?
The components are mostly from GM and have been proven dependable for
over 20 years and millions of miles of driving. Tune ups are far and few between. Maintenance consists of changing filters, spark plugs, and an occasional gulp of fuel injection cleaner in the gas tank. Basic fuel injection components often go for 100K miles or more without adjustment or failure.
Can I buy components to build my own system?
TBI conversion adapters and TPS kits are available separately for use with your own engine management system. Some folks are experimenting with
the low cost Megasquirt.
Are parts readily available?
Yes. Parts are mostly common GM items that your local parts store will carry. Because the parts are used in so many cars, the price is correspondingly low.
How long does it take to get the kit?
Please email me for a shipping date but most kits ship within 2 - 3
What wiring modifications are needed?
The harness is plug and play with the exception of the battery connection. The original harness is
I am not a mechanic, can I do it myself?
Yes. There is good set of instructions with many photos. If you are somewhat mechanically inclined or have a buddy willing to lend a hand it goes quickly and easily.
What is the Idle Air Control and
why do I want one?
The Idle Air Control, referred to as the IAC, is
actually a variable flow valve that bleeds air into the intake manifold.
It’s purpose is to provide air during startup, raise the idle speed
during engine warm up, stabilize idle speed, prevent stalling, act as a
damper during deceleration, and provide additional air during hard
acceleration. Although optional, it’s suggested it be included in all
new installations and is a must on engines with air conditioning or
automatic transmissions to maintain a steady or increased idle speed. We
recommend adding an IAC whenever possible.
Carburetor & Adapter Questions
Can a triple ZS carb setup be converted to TBI?
Yes. We now support the triple carb set up.
Can I convert my TR4A or dual carbed MGB?
Will your TPS driver fit up ok with the round shaft end on the SU Carb?
Yes the SU driver is designed to fit the round shaft.
My carbs are old and in need of rebuilding. How sensitive is your TBI solution to leaks in the throttle shaft seals?
Minor leaks are no problem, they just supply a little extra idle air. Carbs work by air passing over a venturi to pick up fuel but in TBI applications fuel is squirted into the throat not caring much where the air comes from. Should be no problem unless the leak is quite severe making it idle fast.
Do the the mounting holes on
your HS6 adaptor plate align to the three bolt pattern on the HD6 carbs?
No problem. The HS6 adapter is round and held in place by three screws unless you modify the dome to hide / hold it down.
What purpose do the carbs have after this installation other then to house the injectors?
They are simply "Air doors" used to meter air into the engine and house the injectors.
Do the bowls still fill with fuel that's regulated by the floats shutting off the needle valve?
No fuel is in the carb float bowls. The troublesome floats and needle valves are not used.
What modifications are made to the SU carb dome? Is there a hole/slot needed to run the wires?
The domes are only ornamental with TBI. The system operates just fine without them however if you want to hide the conversion, modified domes can be refitted. To modify the dome, the guide tube for the piston is cut off even with the underside of the dome and in most cases the top post needs to shortened about 1/2". Once modified the domes can no longer be retuned to carb duty. The wires run out thru a slot milled into the adapters.
Can it be installed without altering the carb domes?
You have 3
If I send you my
carbs will you do the conversion for me?
It's not necessary to
remove your carbs and send them to me as installing the adapters is
very easy as shown in this video.
Unable to adjust
idle speed down - causes?
Choke fast idle cams engaged
On ZS carbs, the idle stop screw hits a moveable stop on the side of
some carbs. Wire the stop so it's immobile .
Throttle linkage binding or misadjusted
Can I use my Pertronix or Crane
The best option, if available for your vehicle, is to use the Patton
Machine conversion for Lucas distributors which will allow the onboard
computer to have complete control over ignition mapping.
Alternatively, you can use any ignition system that produces a square
wave to fire the coil, but you will need to use our Tach Filter to
provide timing pulses to the on board computer. Use of the Tach filter
and your ignition system does not allow for
computer controlled ignition mapping. Some systems suitable for use
with a Tach Filter are: Pertronix, Crane and 123. If you have any doubt
about compatibility, please ask.
The Tach Filter will not work with points.
Can I reprogram it myself?
The short answer is yes, however AFI does not supply components or support for
do-it-yourself tuning. If you wish to do your own programming there is a lot of
support on the web from sites like tunercat.com. In fact, very very few people
go this route as the professional tuning from AFI is so good.
Your system will arrive preprogrammed and the experts
at Affordable Fuel Injection will help fine tune it to your car and your
driving style. The kit price includes their support and up to three
tuning chips. I would be surprised if it took more than one try to hit
the mark for optimum performance. Should you at some point make
significant changes to your car and have used up the three included
chips, AFI will still work with you however there will be a charge for
AFI does have a service that they will loan you a chip burner (deposit
required) and they will create tuning profiles and you can burn your own
chips. There is an additional charge for this level of tuning. This is
especially suited for one of a kind installations.
What if I have a modified engine?
The present system is running a stock or mildly modified engine. Affordable Fuel Injection can tailor the software at no extra charge up to
three times for most any modified engine.
Where does the ECM computer mount?
Originally we mounted it on the right side within the passenger foot well, and that's still my favorite location. The ECM has been mounted at the very far reaches of the passenger foot well under a panel, under a seat , or even in the trunk. The harness is long enough to mount the ECM nearly anywhere but the trunk will be a tight stretch.
How do you get
WinALDL to work in Vista?
WINALDL will only save files into the WINALDL programs
folder and VISTA won't let any program save files to a folder other than
Documents folder. So to get around this issue we have to install WINALDL
into the documents folder.
site has an excellent tutorial for setting up WinALDL in Vista.
Do you provide for datalogging?
Yes this system has the ability to datalog. A laptop is used to record all the engine sensor readings as well as fuel and ignition timing while driving down the road. Tuning your system amounts to connecting a laptop using the ALDL cable and taking a fifteen to twenty minute drive in varied conditions. The resulting datalog file is emailed to AFI and a new profile is programmed into a chip sent to you for installation.
Why isn't WinALDL
showing any data being logged?
If WinALDL is logging
any data or is logging suspect data, please check the following in the
WinALDL configuration: ECM Model#, Com Port and Baud Rate which must be
set to 4800. You should also check your cable connections and
review the video on
setting up WinALDL.
What type of injector is used?
The adapters are designed to use standard GM throttle body injectors from late 80's and 90's cars and trucks. We use the later style GM mini TBI injector because they
are smaller and fit better in some applications, such as the SU HS6 carb.
Multiport Injectors (MPI) be used?
will not fit the carb adapters that I produce. The TBI Adapters and TBI
Kit that I supply IS NOT compatible with MPI injectors or a multi-port
What is BLM?
BLM stands for Block Learning Mode. This GM ECM has the ability to learn about how you drive and adjust accordingly.
Do you have an IAC?
Initially to keep the cost of the TR6 kit down and keep things simple we
did not use an Idle Air Control Motor. Instead the original choke cables
are used for fast idle warm up as the fast idle cams are still
functional. That still works well and may not even be required in warm
If you run air conditioning or an automatic transmission an IAC circuit
is required to prevent stalling.
On recent systems it is recommended to add the optional IAC circuit when
possible. It does offer automatic fast idle at warm up, has stall
prevention, and follows the throttle on acceleration.
Pricing for this option is on the Order and Pricing page
Does it work with a Turbo
No. This TBI setup is not presently
compatible with a supercharger or turbo. (it may be possible to use it with a
"draw thru" type SU on a supercharger) but again stay tuned.
Is it smog legal?
No. Although it is very likely that a converted car will easily meet your state's smog emission requirements there is no guarantee.
In most cases it will run far more efficiently than as a carbed engine hence less emissions. But for legal reasons I must state "for off road and racing use only".
One customer did take his car through emissions just to see what
would happen and it easily passed.
Do I need a swirl pot?
In case this is a new term to you, a swirl pot is a small reserve tank that supplies fuel to the fuel pump during hard cornering. The stock TR6 fuel tank is not baffled so during a long hard left turn at low fuel levels the pump may starve for fuel. Not really necessary unless you are a very serious autocrosser or run on fumes all the time. A swirl pot can be be added just below the tank and a vent line run back up to the top of the fuel tank. Homemade pots are sometimes made from aluminum air conditioning filter/driers.
Do I need to
upgrade my coil?
Yes you will need to install one of the following
coils which hare suitable for use with this conversion:
NAPA coil # MPE IC88SB
MSD Blaster coils 8200 or 8203
Pertronix 40001, 40011, or 40111
Crane PS20 or PS40
Can I send you my
distributor for conversion?
Please review these two video to
see how easy it is to convert the distributor to electronic. If
after reviewing it you still have concerns, let me know and we can
discuss the alternatives.
Installation & Kit Questions
What type of hose is in the
not included in the kit and must be sourced locally.
systems such as this run at a relatively low pressure. The fuel pump
puts out a maximum of 60 psi however the regulator reduces that to 15
2009: As a result of increased levels of alcohol in gasoline, new types
of alcohol compliant fuel hoses, considered “Green” as in
environmentally friendly, are coming to market. One of these “Green”
hoses is offered by Gates Corp and is their Barricade series (it is
still black in color). Standard fuel hose can be porous to the alcohol
in the gas and often hardens the hose over time. Depending on where you
live, alcohol concentrations and formulas may vary. Most hose
classified as “Fuel Injection” are alcohol resistant. You can also run
steel or copper-aluminum fuel lines.
Do I need any special tools?
Not really but a bung needs to be welded to the exhaust header for the O2 sensor. If you can't do this any muffler shop or neighborhood garage can do it very reasonably. Beyond that a few common hand tools, a hole saw, a 3/8" pipe tap, and a voltmeter are all that's needed.
What is in the kit?
While the kit components are from two separate vendors (Patton Machine
and AFI), the complete kit actually ships from Patton Machine so you're
only dealing with one vendor for your purchase. Included is the hardware unique to convert the ZS carbs or SU carbs to fuel injection. It consists of
one TBI adapter for each carb, a throttle position sensor bracket, actuator, and bypass block off plates, a "plug and play" wiring harness, filter
& relays. ECM preprogrammed for your type of car, fuel pump, regulator, sensors, injectors, regulator, and incredibly important- programming and technical support. There may be a few minor hardware type items that will need to be sourced locally depending on how you layout your system.
Can the process be reversed?
Sure. Converting the carbs back to carbureted use takes only about fifteen minutes especially if you leave your old fuel pump and lines in place. Just remove the TBI adapters from the carbs, drop in the pistons, and put the domes back on. Switch the fuel source back to the mechanical pump and you are right back to a carbed engine. The only caveat is that if you wanted to mask the TBI installation, modification to the original carb dome is required and that precludes it's return to carb use. A spare set of domes is readily available if needed. Of course I can't imagine you ever converting back anyway.
How long does it take to install?
If you have all parts on hand and some help, the installation can easily be done in a long weekend.
Can it be installed in stages?
Yes you can still drive the car while much of the conversion work is done. Things that can be done ahead of time; coolant temp sensor, throttle position sensor, fuel lines, ECM mounting and harness, ignition conversion.
Does the return line connect to the gas tank
and is it required?
Yes, we have tried re-circulating the fuel back to the pump but it heats up so it must be returned to the tank. The tank connection varies from car to car and year to year so you will need to look over your tank connections. Sometimes it can be connected to a vent line and at other times a fitting can be added to the sender for the return. Because of these variations you will need to determine how to connect to the tank. We can help with some applications and can modify or supply fittings for return via the sender at a small additional cost.
What size hose off the manifold is needed for the connection with the map sensor?
1/4" hose barb and keep it as short as possible. Under 10" of hose is best.
Besides the Oxygen sensor welding, what other modifications are needed?
The TPS just bolts onto the side of the carb using the carb mounting nuts. Other than replacing the throttle shaft nut with a special driver nothing is else modified. Just like unbolting the carbs, it is an easier job for folks with tiny little fingers. Installing the TPS can be done well ahead of the actual changeover as it does not affect the carb operation.
Are any special
Optional tools are a digital voltmeter and a GM style OBD-1 code
reader (cheap on ebay). You will need access to a laptop computer to
verify sensor readings, gather trouble codes, and finally create a data
the TPS and I can't get it to read correctly.
Start by reviewing all five (5) videos dedicated to installing the TPS
and if you still cannot get it read correctly, chances are you've
over-rotated the sensor beyond its range and it has been internally
damaged. A new sensor will be required.
Can the black
wires in the TBI harness be connected to the negative post on the
NO......these are signal wires and
must be connected directly to the engine block.
The wire harness
is too long/short.....can I modify it?
The harnesses are intentionally on the long side to accommodate
installing the ECM in various locations. Simply cutting the harness and
splicing it back together with butt splices is NOT recommended. Some of
the wires carry signals operating at low voltage so a poor or corroded
connection will cause a malfunction. Best to find a spot under the
dashboard where a loop or two can be tucked away. Before attempting to
shorten the harness contact Patton Machine or Affordable Fuel Injection.
Does the kit
include a Check Engine Light?
The kit includes a generic round
light which may require the drilling of a hole in the location of your
choice for installation. Another option is to
purchase a Check Engine light from K-Four which will fit one of the
existing holes in your dash.
What fittings come
with the regulator?
I provide an assortment of fittings that should work
for most people. Additional fittings can be bought at most hardware,
auto or home improvement stores.
What are the port
The five (5) fittings
in the red body section are all 3/8" NPT while the one fitting in the
black body section is 5/32" NPT.
What fittings go
The fitting on the
bottom of the red section CAN ONLY be used for the return line to the
gas tank. The other four fittings around the mid-line of the red section
can be used for input from fuel pump, output to injectors and pressure
gauge. Use them in whatever way fits your installation best. The fitting
in the black section of the regulator CAN ONLY be used as the
vent/overflow line in case of a regulator failure.
How do I seal the
fittings so they don't leak?
Use a Teflon based
pipe sealant approved for gasoline on the threads of the fittings.
Can I use the
fitting on the very bottom for anything other then the return line?
NO......that port CAN
ONLY be used for the return line to the gas tank.
Can I remotely
mount the pressure gauge in the car?
gauge MUST BE mounted directly to the regulator.
Does the regulator
have to be mounted in a vertical position?
The regulator can be
mounted in any position that best meets your installation.
Is there any
distance limitations regarding mounting location?
The only limitation
is with the fuel lines being connected to the injectors. Those lines
should not exceed 3 feet in length.
What do I connect
the overflow/vent fitting to?
This fitting does not
connect to anything. Just run a hose from it so that any gas overflow
would run to the ground. It's unlikely that this will ever occur and
it's provided as an overflow safety release point.
What do I adjust
the pressure to?
perform better with the fuel pressure set to 14 PSI. New installations
should be set at 15 to 16 PSI.
How do I adjust
pressure and counter clockwise decreases pressure. Do a complete turn at
a time and then check it and adjust accordingly.
Why does the
regulator show pulsating fuel pressure and/or why is my fuel pump noisy?
In normal operation
the fuel pump will only run a few seconds when the key is first turned
on or if the starter is engaged but the fuel pump runs continuously
whenever the engine runs. Fuel pressure should be set to between 15 and
16 PSI. When the engine shuts off it will take a few minutes for the
fuel pressure to bleed off completely.
Reasons for a noisy fuel pump or excessive
- Fuel level in
tank too low allowing air to be drawn into fuel inlet.
Before troubleshooting pulsing pressure be sure tank is at
least half full.
- Filter plugged.
Remember a filter can plug in an instant if there is dirt in the
- Improper fuel
- Something loose
in tank restricting intake.
- Restrictive shut
- Bad 12V
connection to pump or poor ground.
- Kinked or
collapsed hose on suction side.
- Return not
plumbed into tank.
- Light spring in
regulator, try heavy spring.
connection on regulator not open to atmosphere.
won't go low enough.:
With the regulator pressure adjusting screw backed fully off there
should be no more than one or two psi reading on the gauge if he car has
been shut off for a day or two. With the engine shut off and pressure
bled off at one of the injector hoses (use caution around gasoline) the
gauge should go to 0 or 1psi. If it won't go down the gauge has likely
been damaged by over pressure due to the regulator screw being set too
tight. Remember the gauge only show 0 to 30 psi however the fuel pump
can deliver as much as 60psi.