Main British Car:
1973 MGBGT Toyota 1989 1JZ GTE Twin Turbo DOHC six
MGC GTS Sebring 1JZ
Posted by: swashburn
Date: April 21, 2009 11:53AM
ALEXANDER D. WASHBURN
MGC GTS SEBRING REPLICA
Base car: 1973 MGB GT
Sebring fiberglass flared fenders front and rear, fiberglass front spoiler and MGC hood, safety glass windshield, plexiglass rear and quarter windows. DENTSPORT custom firewall, footboxes and transmission tunnel. NASA-SCCA spec roll cage, fire surpression system, ATL fuel cell. Flexible stainless brake and fuel lines.
Toyota OEM 1990 2.5L Supra 1JZ GTE twin turbo engine, larger intercooler and custom DENTSPORT exhaust system. Remote oil filter and radiator. OEM HP: 285. Engine mounts moved 10" behind stock mounting point for OEM four cylinder engine.
Toyota OEM 1990 five speed Supra gear box with DENTSPORT quick shift, crossmember, and driveshaft.
Front: FASTCARS IFS with double wishbone and custom steering rack and cross member. DENTSPORT custom 1" front sway bar. Penske twin action racing shocks and springs.
Rear: Ford 8.8 with limited slip and 4.10 gears. LEVY RACING three point suspension with coil overs and Watts linkage.
DENTSPORT custom upper and lower control arm chassis mounting points. Penske twin action racing shocks and
Front: 11.75" Wilwood disc
Rear: 10" Mustang GT disc
TILTON style floor mounted brake, clutch, and throttle pedals from the UK.
Wheels and tires
15x8 Superlite wheels with Hoosier R6 245x50x15 tires and Hoosier 225x55x15 wet road race tires
Approximately 2000 pounds empty
In 1968, I saw the MGC GTS factory race car, which had placed 10th overall at Sebring, at Sebring and at the New York Auto Show and that car has always been in the back of my mind. BMC was offering the car for $4000 and I should have purchased it but....When I decided thatmy Factory Five Cobra was not appropriate for the track because it lacked a proper roll cage and fuel cell, the MGC GTS was the obvious choice for a dedicated track car. But I did not want to put a V-8 in the car, since the original car had a deriviative of the Austin Healey 3000 straight six.
My son was co-owner of Dent Sport Garage in Norwood, MA, (dentsport.com) which specialized in turbo applications, primarily on Japanese cars like Subaru, Mitsubishi, Honda and Nisson. He suggested that I consider a Toyota Supra 1JZ GTE straight six double turbo engine, with a Toyota five speed transmission. This 2.5 liter engine produces 285 HP in stock form, and weighs 60% of what the original MGC GTS engine and transmission weighed back in 1968. The engine has a red line of 8000 rpm, and with straight pipes out the side sound similar to the Nisson Skyline engines of Japanese racing fame.
I rented a two car garage space next to my son's garage, and the project has began in 2010. The car was stripped to the bare frame and then sand blasted before a SCCA spec full roll cage was installed. The 1JZ engine and transmisson was fitted, with the engine mounts moved aft about 10 inches so that the weight balance in the car would be more neutral. Superlite 15x8 wheels were choosen, which just fitted the Sebring flared fenders, which I installed on the body myself. The car was painted the same dark British Racing Green as the original MGC GTS with a yellow Sebring lower front valance. My goal was to keep the cost of the project below $20,000 by doing most of the work myself, except for the roll cage. Pictures to follow.
The front suspension chosen,built by FASTCARS, is a custom lightweight unit which has 11.75 Wilwood brakes. For the rear, I ued a shortening 1995 8.8 Ford axle with positraction and 10.5" discs with a 4.01 ratio. I decided to use a 5 link system made by Gordon Levy of Levy Racing in Phoenix which incorporates a Watts linkage. This unit was designed for the Factory Five Cobra replica, but fits the MGB frame within 1/2". 15x8" Superlite wheels should help keep the weight below 2000 pounds, particularly considering that the FastCars front suspension weighs 80 pounds less than the stock MGB suspension.
The purpose of this car was to run in time trial events on the east coast starting in 2011. Hill climbs may also be attempted but the chance of crashing in these events is probably too high for me. Vintage racing is not possible because of the suspension and engine modifications to the car. Sound is a very important part of the car to me, and double straight pipes out the passenger side were fabricated to obtain the best sound from the high reving engine. The car was built to be a dedicated track car and has not been registered for road use.
While many MG enthusiasts are familiar with the FastCars IFS setup, the Levy Racing Watts link rear suspension option, which uses an 8.8 Ford rear end, is probably a new concept. Since I built a Factory Five Cobra replica, I had heard about this racing setup which is totally adjustable and very strong. The picture shows the unit installed in a Cobra chassis, but the width of the unit is within 1/2" of the MGBGT frame over the rear axle. Before the full roll cage was installed, I welded in the Levy unit, which became the rear mounting point for the roll cage.
When I was in Dallas Texas in 2011 I stopped at the JDM Engine Company which imports engines from Japan. I picked out a clean 1JZ GTE engine and transmission which included a clean uncut harness and ECU specific to the manual transmission engine. The cost was $2,000 with free shipping. By the time I returned to Boston at the end of the week, the engine had arrived at my garage. The engine was fitted to the MGB engine bay 10" behind the stock mounting points and a completely new firewall and transmission tunnel was fabricated by my son at DENT Sport Garage.
On the body, the only body repair to the donor was replacing the rocker panels which were the only section of the body with any rust, which is quite extraordinary considering the car was in Pennsylvania much of its life. The fiberglass Sebring flared fenderswere riveted onto the steel body. The rear fenders fit quite well, but the front fenders were difficult. I purchased a second set of the Sebring flared fenders so that if the car is involved with an offroad incident at the race track, I would only need to replace the fenders which are riveted on.
The 8.8 rear end shortened by 10 inches and installed with the Levy Watts Linkage set up. The FastCar IRS was supplied with an added one inch on each side to match the Sebring flared fenders. I decided to use a front spoiler from John Targett. The Kirkey Intermediate race seat is mounted with welded supports which bolt through the side of the seat for stability and bolt to the roll cage behind the seat. I esed a Tilton style floor mounted brake, clutch, and throddle unit with remote reservoirspurchased in the UK.
I spent three days at the Sebring 12 hour race week in 2010 watching vintage racing and talking with the car owner/drivers. Jerry Richards was there with his 1973 MGBGT V8 race car which is one of the fastest MGBs in this country.
Jerry is British but has been in the US for many years and he has built four MGBGT V8s and is working on building an exact replica of the 1969 MGC GTS factory race car which I am also building. Jerry has fabricated his own flared fenders and does all the work on his cars at home in Atlanta. He has been an inspiration to other MGB GT V8 racers and I know that I found the mentor for my car build.
August 9th 2011 - The car has been painted BMC "New" British Racing Green which is the super dark green color used on the factory race cars in 1969. The front spoiler has been painted yellow to match the original RMO 699F. My son found Penske Racing triple action racing shocksfrom a British touring class race car on the the UK Ebay which we purchased for 25% of the new price. These are used on race cars with double wishbone suspension and should be perfect for the MGC.
I ordered a used APEX Power ECU for the 1JZ from a source in Japan which allowed us to tune the engine on the DENTSPORT dyno so that the engine would have no rev or boost limiter and the timing could be adjusted to an optimum setting. This resulted in 285hp at the wheels from a conservatively tuned and durable engine. My son stripped the Toyota wiring harness of unneeded wiring which will eliminate about 50% of the bulk. I plan to use a Stack tachometer and a very accurate French turbo boost guage which he and his friends have used successfully. Steering linkage was fitted to the custom manual steering rack supplied with the FASTCARS front suspension. A custom dash panel was also be fabricated.
The turbo intercooler system was fabricated by my son as well as the custom radiator. He also fabricated a two pump fuel system with a surge tank which feeds the 1JZ from the ATL fuel cell. All fuel hoses are braided led through the interior of the car, as are the braided staimless brake lines. A FireCharger fire suppression system has been installed with 3 nozzles.
The car participated in a two day time trial at New Jersey Motorsports Lightning track on August 1-2 2011, followed by the Duryea Hill Climb in Reading PA in mid August. Performance exceeded expectations and the car attracted a lot of attention at the hill climb because Reading has quite a few MG and vintage car enthusiasts. We rebuilt the turbos after the hill climb because the seals were smoking from leaking oil. We also replaced the brake master cylinders with Wilwood units which made a big differnece in brake pedal action. Last week I participated in a two day time trial at the New Hampshire Motor Speedway and my son and I travelled to Watkins Glen the next week for two days of time trials.
In April 2012, I ran the car at Summit Point Raceway for two days at a time trial and the car ran perfectly. During the winter, I had upgraded the front brakes to six piston Wilwood calipers which made a tremendous difference in braking power. The next event on Memorial Day weekend was a time trial at New Hampshire Motor Speedway. During practice on the second day, after driving 75 perfect laps while qualifying for a COM competition license, I entered turn 11 too fast and the car did a 360 at speed and crashed head on into the inside wall at about 50 mph. Needless to say, the car was a wreck but I survived fine thanks to tight racing restraints and a HANS device. My son and I along with a body and frame specialist rebuilt the car in less than two months. Photos below show the damage and the car after Chris Howard worked his magic transformation on the front frame while adding roll cage bars from the frame to the SCCA roll cage in the cockpit.
In April 2013, I returned to Summit Point where the car ran perfectly. This was followed by two days at New Jersey Motorsports tracks, Watkins Glen, and Lime Rock where the car had no issues. My last event of the year will be
at Watkins Glen for a time trail in September. For the last two ebents, I was able to run with a D Type Jaguar replica
since both cars have the same weight and horsepower. That was the most fun I have ever had on a race course. During
the Watkins Glen event, we did a walk around the race course which was a real eye opener. Amazing banking and
steep hills which are nor really evisent from inside the race car.
testing: 1, 2, 3...
Edited 73 time(s). Last edit at 08/22/2013 01:55PM by swashburn.