![]() Updated: 21 September, 2000 This web Page has been created by Dave Munroe of Waverley, Nova Scotia, Canada, with the help of his son Don who knows more about computers than his Dad does about cars. Thanks, Don! I am also grateful to Wayne Kube, of Plano, Texas, who allowed me to steal some neat boilerplate MGB images from his MGB Art website to make this site a little more attractive. Thanks, Wayne!
I have a 1974 MGB Roadster that was built by a talented previous owner from pieces and parts of more than two cars. On first inspection, it looks original, but closer examination will reveal to the enthusiast several clues to it's mixed heritage. It has 59,000 miles on the clock, and I have no clue as to the accuracy of this mileage.
As it is not an original, and never can be an original, I have been freed from the need to stay with original equipment, and am not constrained from adding just about anything to my "B" that will make it more fun to drive and more interesting as an MGB hotrod...even if it will not be well recieved by the concours crowd.
This is where you begin: the air filters, carbs, intake manifold, all vacuum lines, hoses, rad and hoses, and pulleys are removed. If you don't already have a set of big bore headers installed, now is the time. The crankshaft pulley is still on because it has to be marked and the crankshaft positioned so the new pulley can be accurately marked for TDC. (The new pulley is not marked due to the large variety of pulleys and timing strips installed on the MGB motor during it's production). Also, I couldn't get the darn thing off, even using my 30" breaker bar. More about this later.
This is the the view from the "business" side of the motor. Should be easy going from here. This is the pile of stuff removed for the supercharger installation.
Here we have what you get for your money from Hi-Flo with your supercharger kit. In addition to these parts, you should also have,
as previously mentioned, a good set of large bore headers, an electric fan kit, and a solid motor.The alloy valve cover is not included in the kit, but available from Hans for a few extra bucks.
The supplied parts are very high quality and truly beautiful. Check out this waterpump pulley and shims.
Now we begin in ernest. The radiator mods are first.This is the radiator as found in my car. The bottom tube is pointing up and is parallel to the rad. If the hose were fitted here, it would foul the new serpentine pulley and belt system. The rad needs to be modified to allow a new hose to be fitted to clear the belt, by soldering a new outlet tube on the rad where I have marked it with a yellow "X".
Here you can see how the new rad-to-waterpump hose fits to the lower rad tank. It wants a tube that is fitted at 90deg. to the tank in this new location. This involves removing the original tube and blanking off the hole with a plug; fitting the new tube, and while we are at it, having a proper drain valve fitted so I can drain the cooling system without covering the garage floor with coolant. The finished rad. Long story, keep it short: original rad had been modified, installed, electric fan installed, rad leaks. Back to rad shop for new core, paint job, re-installed electric fan, back in car, finished. Thought I HAD a good rad to start with..... The new pulley is not marked for Top Dead Centre, so it is important to roll the #1 piston to exact TDC, make sure the timing marks line up, (painted here to make the marks easier to see), and hold everything tight while the new pulley is replaced. It can then be permanently marked to the existing timing strip on the block for accurate timing use in the future. The bolt holding on this pulley was a particularly miserable sob to remove. I had removed the cylinder head to "freshen it up", and had no good way to hold the crankshaft from turning while coming on to my 30" breaker bar with the 6 point socket on the bolt. Calls for help on our local club Bulletin Board produced no end of innovative, but alas, unsuccessful ideas. .In the end, I got a great tip from the resident wrenches at the local Motorcycle shop. I was advised to crank up the compressor to 120psi, get the socket ready on the bolt, fill my 1/2" air impact gun with ATF through the hole where the hose snaps on, and let 'er rip. With son Don on the foot brake and the tranny locked in 4th gear, I got everything ready and pulled the trigger. I swear it didn't hit the bolt twice before it broke loose and spun off that pulley! Its a great day when you get a tip like that... Here is the new crankshaft pulley, with integral "racing bolt lock" that I found out later fouled the steering rack, so I had to remove it. The new TDC mark has been centerpunched on and painted for clarity. The crankshaft pulley is the"datum" for alignment with all the other pulleys, which have to be shimmed to very close tolerances. It is a tribute to the engineering quality of the specially made parts that the supercharger pulley lined up perfectly. It is attached to the cast intake manifold (opportunity 1 for misalignment) which is attached to the cylinder head (opportunity 2). The waterpump pulley came with a set of shims, used all but one; and the idler pulley, which came with its own exquisite little alloy casting, was also perfectly shimmed right out of the box. The alternator pulley was firmly mounted to the alternator, and the alternator itself was moved in its bracket with supplied washers. Too bad you couldn't drive around without the radiator and show off the neat serpentine belt drive system! The intake manifold flanges where they bolt ont the head are quite a bit thicker than the exhaust manifold flanges, so spacers have to be made to fill in the gap. It is important to have these spacers the proper thickness,otherwise one of the two manifolds could be left slack and allowed to leak. As it turns out, the original thick manifold washers are the exact proper dimension, and cutting two of them in half and grinding the outside circumference to fit the manifold depression was the perfect solution. Here you can see the mis-match in the thickness of the intake and exhaust flanges where they bolt onto the head. Not a difficult task to solve, but a fairly critical dimension, none-the-less.
Now i'ts coming together. Most of the mods to the engine room have been completed, so now we were able to bolt the carb to the supercharger, and then fit the supercharger to the intake manifold.
Cables next. Small fingers are the order of the day, as the linkages are between the carb and the manifold. Not much room to work.
This is the 10" Hayden fan that I installed. Its about the largest you can get in there. A 180 degree sensor switch is mounted between the fins of the rad, and I wired in an override switch which is mounted on the front center consol beneath the radio.
The Hayden cooling fan came with a relay, so while I had everything torn apart, and in an inspired moment, I decided to wire all the heavy electrical components through relays, as recommended by all the gurus of LBCdome. I made up an aluminum panel and mounted relay recepticals to it. It installed neatly behind the original MGB fuse block on the passenger side inner fender. (oops, excuse me....wing!).
The finished look!
Who would believe what lurks beneath the hood of this innocent looking MGB? Maybe what's under the rear bumper will give it away.......
21 September, 2000
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