Bob Hyclak's 1974.5 MGB with Rover 3500S V8
(originally published in British V8 Newsletter, Volume 5 Issue 1)
By: Bob Hyclak
City: Clearwater FL
Model: 1974.5 MG MGB
Date of Conversion: August 1994 - January 1995
Engine: 1970 Rover 3500S 3.5 litre
How It Was Done
|Engine:||complete overhaul including reduction of compression from stock 10.5:1 to 8.8:1,
completely balanced, Buick 4bbl intake manifold with AFB carburetor. Delco
distributor with Allison ignition. Accel Super Coil. Accel Superstock
solid core ignition wires. (Wreaks havoc with any television or radio within 50 yards,
but gets the job done!)
|Transmission:||1980 Rover 5-speed from SD1, used trans with 60M miles and no problems.
|Bellhousing:||1980 Rover SD1.
|Clutch Slave:||1979 Triumph TR7 with no modifications other than adapting TR7 hydraulic line to
MGB clutch master cylinder.
|Clutch:||1980 Rover SD1.
|Flywheel:||1980 Rover SD1.
|Exhaust:||factory MGB/GT V8 cast iron exhaust manifolds with dual pipes.
MGB front mufflers with Ansa resonator tips.
|Brakes:||stock MGB, rebuilt.
|Wheels/Tires:||14x6 Toyota Celica wheels. (They look like MG Ltd Edition wheels.)
Fronts with 1/4" spacer to clear tie rod ends, and notched to fit front hubs.
Rears needed no modification.
Tires are 195/60x14 front and 235/60x14 rear.
|Suspension:||replaced lower control arm bushings and added 1978 MGB rear sway bar.
Front sway bar was spaced approximately 1-1/2" down from frame for oil
filter and lower radiator neck clearance.
|Cooling:||currently using an aluminum tube type radiator from a Renault Alliance
('77, I believe.) Radiator lower neck required low mounting of radiator
in chassis. Surface of fins/tubes approximately 16"x16" (256 square inches)
vs. MGB 18"x12" (216 square inches). Crank driven 7-blade plastic fan
blade with auxiliary electric fan in front of radiator.
|Rear End:||MGB stock 3.9:1. Driveshaft was stock 1976-80 Spitfire non-overdrive
with CV joint in front intead of straps. Front flange was redrilled for
5-speed bolt pattern. Rear flange replaced with MGB (Spitfire and B share
|Instruments:||Stewart Warner marine electrical tachometer. (Same size as MGB.)
Also used Stewart Warner mechanical water temperature gauge in original MG
water temp gauge location. A cable was fabricated to match TR7 trans
to MGB 120 mph speedo.
|Sources:||best parts sources were friends (motor head types) and Hemmings Motor News.
Information was obtained anywhere I could get it.
V8 Conversion Company, Glen Towery (Towery Foreign Car) and
Ted Schumaker (TS Imported Automotive), other converters, and
Hardcastle's book (Tuning the Rover V8).
Don't be unduly influenced by the "gurus" - follow your instincts and common sense in choosing hardware and/or techniques. You won't get to the head of the pack if you follow someone else. Use cost/benefit ratio to determine your approach (if $ matter). Use of Rover or Trumph cylinder heads simplifies accessory mounting.
What would I do differently? This type of car should always be in the process of change. The only thing I wish I would have done in the process is to go for more performance, cam/compression/head work in advance of installation.
My MGB is a 1974.5 rubber bumpered roadster, providing the enlarged engine bay and being an emission-except model here in Clearwater. (Only 1975 and newer cars are subject to tailpipe testing.) By the time you read this, I should have a performance cam installed - the stocker is too mild. The intake manifold is a 1963 Buick with a '67 Buick 340 AFB carburetor, fully rebuilt and re-needled. On the exhaust side I managed to locate a pair of original factory cast-iron manifolds from a fellow who had worn out his conversion project, having started in the early 80's. The system is dual all the way back, due to relocating the the fuel tank to center. The current driveshaft is super strong but I haven't had to test its abilities yet - there is great temptation to drop the hammer and dump the clutch, but so far I've been good. The 3.9:1 rear end gears add to the accelerative punch of this quick winding short stroke motor, and since I don't anticipate cruising in the 100+ mph range I will not even consider a numerically lower ratio. The overdrive 5th gear and the tall 24.75" diameter 235/60R14 tires bring 60mph in at around 2700 rpm.
From the miscellaneous details section, I used early Rover engine brackets with '79 Volvo 242 rubber isolators - no mods to chassis. Rear is supported by MGB crossmember moved back and reversed. Trans is isolated by '73 and newer TR6 transmission mount rubbers. The oil pan was donated by a TR8. Alternator is a Delco 63 amp unit with integral regulator. Alternator is mounted on a '67 Buick bracket on right cylinder head. Radiator will be large cored aluminum soon. Currently is aluminum with dual row of tubes (Scirocco style) donated by a Renault Alliance. So far the cooling has been adequate, but running it hard brings temperatures up to 205 degrees with a 160 degree stat and I want to add air conditioning. The Camaro guy yesterday was probably very grateful he still had a little nitrous in the bottle, still he had a very puzzled look on his face! I only wish I had done the swap sooner - every MGB owner would line up for one after driving it. Awesome!