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 thetrip to The Roadster Factory Summer Party in Indianapolis Pennsylvania. The first big trip, about 7 hours to get there, was very enjoyable anduneventful. 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 incase 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 wiredup 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 Iemptied 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.
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 alittle 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. Movingto 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. Newfront 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 checkthe rear wheel alignment as it can cause the same problem.
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 Shumacherof 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 asbadly. 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 thatincluded 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 bushingsinstalled, the car tracks like it is on rails.
The final suspension improvement was a big investment in high performance shock absorbers. I settled on the SPAX Gas Adjustable shocks as they could beadjusted 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 thebig 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 moneyon 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 electronicignition 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 distributorsthat 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 wasrunning 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 timinglight. 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 PertronixIgnitor 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 theFlame-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 tohow 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 asmuch 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 performanceexhaust.
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 installingthis 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. Ireplaced 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 bereduced 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 tobe 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 headwithout 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 slipof 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 thevalve 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 machinethe 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 exhaustsystem. 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 theexhaust 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 majorblock 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.