No, however each of these modifications if selected carefully, alone or in combination will yield increased performance and increased economy. A smoother, quieter more responsive engine will be the result.ĭo I need to change carburettors, manifolds, camshaft and exhaust system? Cylinder head wear will be almost negligible. The combination will delight you in performance and reliability, most likely outlasting your ownership of the vehicle. Yes, the best time to take most advantage of roller rockers is when you fit a new cylinder head. Would roller rockers be a good idea to fit with my new head?
No, in most cases standard tuning specifications will give the best results, but it will depend on other modifications What really matters is the breathing and cylinder filling efficiency of the head at medium to higher engine speeds, that’s what really improves power and performance. In road applications today’s fuels cannot tolerate higher compression than or original, knocking, pinging or severe engine damage can result from too high a compression ratio. Quoted compression ratio appears to be about standard, wouldn’t it be better to have a higher compression ratio? Of course if you drag race from every stoplight, your engine life will be shortened and fuel consumption increase. No, engine life generally increases as you no longer have to rev your engine as much to produce good useable power. Will Yella Terra heads shorten the life of my engine? With the power improvement gained, you use less throttle for the same speed so the economy is generally improved. Will a Yella Terra head affect my fuel economy?
“cylinder filling” and increase performance by allowing more air/fuel mixture into the cylinder and burning the mixture and exhausting the spent gas better than standard – yielding extra power. How do Yella Terra heads improve performance?Ĭompared to an athlete’s breathing exercises to improve performance, Yella Terra heads improve the breathing of an engine i.e. Valves are diamond hard and have incredible wear resistance, valve guides & stems don’t wear, increasing head life dramatically, possibly as much as four or five times that of a standard head. The diamond honing process provides perfectly sized, accurate and straight valve guide bores with a cross hatch surface (as with cylinder bores) to provide the best oil retention and wear resistance. What are the advantages of Diamond honed valve guides and tuffrided valves aptly named “DOUBLE DIAMOND”?