my brother in law has purchased a COBRA replica and hes sorting out a few issues.
one rather puzzling issue was the car runs fairly decent under normal driving and produces decent power, BUT!! if you accelerate hard for about 20 seconds , any sustained power seems to gradually nose over then the power drops off and theres a significant drop in power,until the cars allowed to cruise at lower engine speed for a minute or so,if you cruise for awhile it works fine again, for a short time, as A test I suggested he leave the gas tank cap loose and sure enough the issue disappears indicating that the air vent that allows air to replace the volume of fuel being used is very restricted and that affects the fuel pumps ability to pump fuel from the tank,as the fuel tank caps not vented. his fuel tank gas cap is the type pictured above with a cam lock on a rubber seal thats almost air tight!(many racing organizations won,t allow vented gas caps on fuel tanks ) the fact that performance returns indicates the air does leak slowly back into the tank but at a slower rate than ideal under high fuel use conditions so he needs to replace the BOLT with a one way flow air vent, that prevents fuel from sloshing out but allows air back into the tank
a quick inspection showed the previous owner plugged the fuel tank air vent hose!
https://encrypted-tbn0.gstatic.com/imag ... ofIifn7UAw
http://www.summitracing.com/parts/sum-220020
one rather puzzling issue was the car runs fairly decent under normal driving and produces decent power, BUT!! if you accelerate hard for about 20 seconds , any sustained power seems to gradually nose over then the power drops off and theres a significant drop in power,until the cars allowed to cruise at lower engine speed for a minute or so,if you cruise for awhile it works fine again, for a short time, as A test I suggested he leave the gas tank cap loose and sure enough the issue disappears indicating that the air vent that allows air to replace the volume of fuel being used is very restricted and that affects the fuel pumps ability to pump fuel from the tank,as the fuel tank caps not vented. his fuel tank gas cap is the type pictured above with a cam lock on a rubber seal thats almost air tight!(many racing organizations won,t allow vented gas caps on fuel tanks ) the fact that performance returns indicates the air does leak slowly back into the tank but at a slower rate than ideal under high fuel use conditions so he needs to replace the BOLT with a one way flow air vent, that prevents fuel from sloshing out but allows air back into the tank
a quick inspection showed the previous owner plugged the fuel tank air vent hose!
https://encrypted-tbn0.gstatic.com/imag ... ofIifn7UAw
http://www.summitracing.com/parts/sum-220020
