Tim O'Brien's 1973 MGB with Ford 2.3L Turbo
(originally published in British V8 Newsletter, Volume 13 Issue 2)Owner: Tim O'Brien
City: Atlanta, GA
Model: 1973 MGB Roadster
Engine: Ford 2.3 liter Turbo 4 cylinder from a 1985 Merkur XR4Ti
Conversion performed by: Owner
Engine Mods: | 1988 Turbo Thunderbird head with roller rockers. Ported heads. Larger exhaust
valves. Combustion chambers match-ported. Ports and combustion chambers ceramic coated.
Head milled 60 thousandths. Custom made header, this was done for the obvious increase in horsepower but mainly to move the turbocharger to a better location. Cut and gutted intake manifold. This was done to increase airflow and reposition the intake to clear the MGB hood. |
Transmission: | 1988 Ford V8 5-speed. Clutch and throw-out bearing are SVO Mustang. Bell-housing and
clutch slave cylinder are 1987 Thunderbird Turbo coupe. This bell-housing uses a
hydraulic slave cylinder to operate the clutch. This way I could use the MGB hydraulic
clutch master cylinder with out going to a cable, like the Mustang uses, or a hydraulic
throw out bearing. |
Cooling system: | 1965 Ford Mustang radiator and 10" electric fan. Hoses are sections from different
hoses I found with the help of local NAPA store. |
Exhaust System: | Custom built header with 2.5" pipe with no muffler except for a 24-inch "Cherry Bomb"
at the rear of the car. The turbo acts as a muffler and the car is very quiet with
little backpressure. |
Suspension: | Stock except for V8 bushings (front) and tube shock conversion (rear). |
Brakes: | Stock. |
Wheels & tires: | Momo 14"x 6" wheels with 195/65/R14 tires. |
Est. Cost: | $3000 - $5000. |
Tim wrote:
Stock MGB's are not as fast as they look. They handle well enough and the brakes seem to be
more than adequate, but they just don't perform like they should. I felt that I had to do
some thing about that. After a lot of research and a few false starts, I decided to swap out
the stock 1800cc MGB engine and transmission for a 2.3 liter Ford turbo engine and a Mustang
5-speed. Ford used this engine in their German car the Merkur, the SVO Mustang, and the Turbo
Thunderbird. When I went shopping for the engine I looked for a whole car. The engine has
electronic fuel injection along with the turbocharger and is computer controlled. I wanted
the entire car so that I could transplant the computer, sensors, and the wiring harness to
the MG at the same time I changed the engine.
I found a car that I wanted, a wrecked 1985 Merkur XR4Ti. I had it towed to the house and
had it put in the garage where I extracted the engine and all of the necessary electronics.
I sold the Merkur transmission and mated the engine with a 1988 V8 Mustang 5 speed. The V8
transmission is different than the 4 cylinder version, and although some machining was
required, the Mustang gearbox is stronger than the Merkur and I felt the gearing is better
for the weight of the MG. Just as a note: the Mustang gearshift comes out of the transmission
tunnel just about a half inch behind where the stock MG shifter came out.
With a lot of fitting, some welding, bending, cutting and other fabrication, along with
numerous trips to NAPA- I finally squeezed the Ford engine into the MGB.
With the engine mounted, the next step was getting the Merkur wiring harness hooked up with
the MGB harness. Even though I thought I took every precaution when removing the wiring from
the Merkur and recording where every wire went, I still ran into some problems. I got
schematics off the Internet and called every body I knew that I thought could help and
finally got it done.
I bought a new 1965 Mustang radiator to cool it. I had a drive shaft made to attach the
Mustang transmission to the MGB rear end. I have had to do a lot of little adjustments
and have had to do a few things over, but all in all it is a good swap.
I am very happy with the swap. I had a few problems after I first finished the engine
change that required I do things a little differently than originally planned, but all
and all it's OK. I changed the motor mounts to give the engine the ability to move a
little more than the way I originally mounted it. This got rid of a lot of the vibrations.
I moved the wiring around a little bit, but I'm still not happy with the way it is laid
out so I think that will be my next winter project. I may even do a whole new wiring
harness at the same time.
The car runs strong and drives well with a great deal of power, especially in the higher
gears when the turbo starts building up pressure. I can cruise at 80 MPH all day at 2600
rpm with plenty of punch and still get 30 mpg.