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After getting the Spitfire to run well enough to enjoy it, I started to make improvements to make it run better and more reliably. By the end of July '97, everything was good enough to make the
trip to The Roadster Factory Summer Party in Indianapolis Pennsylvania. The first big trip, about 7 hours to get there, was very enjoyable and
uneventful.
The only people that work on my car are me and my mechanic, shown here finishing up after adjusting the valves.
Fuel Pump Surprise
I found that the previous owner had installed an electric fuel pump. The mechanical one was still in place but didn't work. It was replaced with a new one and I left the electric pump in place in
case of future problems on the road. Now I can just flip the electric fuel pump switch on to get things rolling again. A good plan that has never been activated.
Fixing the Little Bugs
Lots of little things didn't work when I got the car. Windshield wipers and washers, radio, overdrive, fuel gauge are a few of the bugs that had to be wrung out. The overdrive was simply not wired
up correctly. The washer pump had to be dismantled and I found the leather all dried up. A little oil to soften the leather got the pump working again. The fuel gauge never moved off a 1/4 tank so I
emptied the fuel tank and removed the sender unit in the trunk. The arm was frozen in place by some old varnish. I worked the arm loose and cleaned up the varnish. Voila, the gauge worked again.
These things were typical of taking over the care of a 21 year old car. You need to touch just about everything to make it all work right again.
Whoa Baby!
Brakes! Whoa they didn't. After driving the car home from the auction, I knew the brakes were not up to snuff. The car just didn't stop well. The front pads were serviceable and the rotors were a
little thin and grooved, but not bad enough to be the problem. The rear was now the likely candidate for the problem. After removing one drum, a shoe lining just fell to the ground. Problem 1. Moving
to the other side, revealed a drum and shoes covered in brake fluid. A leaky slave cylinder was the culprit so that mandated replacing the slave cylinders on both sides along with new shoes. New
front rotors and metallic pads were added later.
Stand Up Straight
Like many Spitfires of this age, the rear wheels leaned in so the tires were wearing on the inside edge. A new rear spring was installed to cure the problem this time but you also have to check
the rear wheel alignment as it can cause the same problem.
Steering
The steering left a lot to be desired as the car would wander with the changes in the pavement. It would also keep on turning slightly after returning the steering wheel to centre. Ted Shumacher
of TSI Automotive suggested a new set of poly steering rack bushings. That cleared up the after steer but the car tended to still wander, but not as
badly. Something was still loose and worn in the suspension. SpitBits had a special sale on of poly bushings for the front and rear. I bought a set that
included bushings for upper and lower a-arms, and rear radius arms, sixteen bushings in total. Poly doesn't give like rubber bushings so the suspension has reduced play. With the new poly bushings
installed, the car tracks like it is on rails.
Smooth Ride
The final suspension improvement was a big investment in high performance shock absorbers. I settled on the SPAX Gas Adjustable shocks as they could be
adjusted on the car. Koni shocks were adjustable but you had to take them off the car. (Koni now has on-car adjustable shocks). The SPAX shocks made such an improvement that is was just
...hmm...shocking!. The little bumps are absorbed with even noticing them while the big bumps are smoothed out. Cornering in the bumps is vastly improved. The car is so much more sure-footed that the
big investment has proven worthwhile. The original shocks just don't come anywhere close to the SPAX and I doubt that even new ones would be much better than the old ones I took off. Spend your money
on good shocks such as SPAX, or Koni, or lower cost KYB.
Just the Right Spark
British cars have been notorious for unreliable ignition systems. Many of them have Lucas ignition systems and this is true of Triumph. The 76 Spitfire originally was equipped with an electronic
ignition build right into the distributor. Unfortunately, these would often fail, usually due to the heat buildup within the distributor. Many were converted over to older points-style distributors
that had no electronics in them and were more reliable. Even these were not great as the spark was often weak and the distributor bearing wear would result in inconsistent sparks. While mine was
running OK, I knew it wasn't perfect as I could see the spark timing moving slightly due to the wear. I could also tell the spark was weak as it would not trigger the pickup to the electronic timing
light. The only way to set the timing was to use an older neon flasher timing light. I looked around for new ignition options and chose the Pertronix
Ignitor as the entire electronics fit under the distributor cap, resulting in a stock-looking setup. The Ignitor fixed the wandering spark timing and gave a nicer spark. Then I added the
Flame-Thrower high voltage coil and a set of new high voltage silicon Pro Resistor Core 8mm High Performance Spark Plug Wires from Taylor.
The new coil can now fire the electronic timing light so there is evidence that the voltage is higher and the sparks are more powerful. The result of the ignition upgrade is instant starting,
smoother idle, and better road performance...and I never have to change points again.
The Current State
At this point, the Spitfire is running very well and the current projects are to upgrade the engine performance and gain horsepower. There are many views on what is best but it all comes down to
how much you are willing to pay. I choose to keep the costs under control and not over spend. The trick is how to get the most gain for a modest outlay. I will also so the upgrade in stages and do as
much of the work myself as practically possible. The first round of upgrades includes a new carburetor, intake manifold, porting and polished head, triple ground valves, and high performance
exhaust.
The Weber DGV 32/36 is downdraft carburetor that should be more reliable than the existing Zenith-Stromberg and will deliver a greater volume of fuel when needed. When I first tried installing
this carb, the air filter would hit the hood when it was latched closed. The Cannon intake manifold was the culprit, although it seems to work for other people, it didn't work for this car. I
replaced the Cannon with a Pierce Manifold that lowers the carb about another 1/4", enough to clear the hood. I will also have to solve an issue where the positive crankcase ventilation must be
reduced or else oil will be coming out of the dipstick due to over pressure in the crankcase.
Porting and polishing the head is the biggest and most complicated part of this project. I have read several books and articles on how to do it, all very informative, but none definitive enough to
be comfortable. The common thread for the Spitfire 1500 engine is to keep the changes to minimum, cleaning up the rough areas and restrictions to flow. BIG problem. I didn't want to do my head
without having done the job before so I bought a used head to practise on. It didn't matter if I butchered it as it would never return to service. The one thing I have learned is that one little slip
of the grinder can chew away and destroy a valve seat in very short order. To prevent that I have tried a trick that may be new, or maybe I just don't know if anyone uses it. I am protecting the
valve seats with a liberal coating of Plasti Dip, more commonly used to coat tool handles. After porting and polishing, I'll that the head to the machine shop to put in new valve stems and machine
the valves. I hope to have more details on this part of the project after I get things running again.
The last part of the project is a high performance exhaust system from Rimmer Brothers. I choose the Single Large Bore Quiet Stainless Steel exhaust
system. It comes with a 4-2-1 header for improved mid range performance. The Quiet option of the system adds small resonator that reduces overall noise. This system will allow free flow of the
exhaust and result in added horsepower. The exhaust tip at the rear is highly polished stainless that will also look superb.
The should deliver several more horsepower, maybe about 5-10, which doesn't sound like much, but will be significant for the existing 50 horsepower. For this round of changes, I am avoiding major
block work. No milling, no shaving, is in this project. In another year, I will replace the camshaft with a mild performance cam and maybe up the compression.
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