Triumph Repair: MKII engine loss of power, low pressure gauge, vacuum gauge

Question
Howard-

I recently started a restoration of a 1967 Triumph MKII Spitfire.  I finally got it running this weekend, but when I get it into third gear, it gets to 40 mph but does not accelerate any higher.  The car does not slow down, but stays stagnant.  Any thoughts on what may be the issue?

Answer
Hi Ashkahn,
That is a normal symptom of a partial stopped up exhaust syatem. There are several methods to diagnose this and the simplist straight forward test is to loosen the exhaust from the exhaust manifold and protect anything close so it does not get the hot exhaust blowing on it and make a quick test drive. Another 100% sure test if the pipe to manifold bolts are rusted badly is to take a short piece of brake line (about 2 inches long) and drill a hole in the exhaust pipe close the the front just a slight bit smaller than the line piese and drive the piece of brake line into the pipe and attach a long hose to the line up to a low pressure gauge (a vacuum gauge usually has a section for low pressure to test fuel pressure) and place the gauge under a wiper arm and make a test run. At no time must the pressure go over 1.5 PSI. If it goes up to 5 to 7 PSI quickly you for sure have a stopped up exhaust. (Don't run it long as the heat from the exhaust will melt the hose)
Howard