Hybrid-SA wrote:Hi again
Here in South Africa my mates are battling to extract power out of the 20 valve motors for a number of reasons.There is :
-No good degree cams that work
-Head cannot be worked further [gasflowed]
-etc
Cams are limited in lift because of the size of the buckets. However both 20 valves flow well stock and have little need for massive lift. There are many a good grind for the 20 valve its just a matter of getting a grinder who knows a bit about the 20 valve.
Head can be worked. In the silvertop its mainly matching the manifold (or rebuilding it to downflow) intake port post choke and exhaust port hogging out. Blacktop also has issues with poorly designed port dividers, but a greatly increased exhaust port diameter.
Building an enigne is all about what you want from the engine. You cant just throw a set of components together and hope it will do what you want it to do. My enigne for instance is built for 200hp and that only! In order to make 210hp I would have to reflow the head, change cams, retime the cams, alter compression, construct a new intake manfold and alter the trumpet length. It would give me 210hp but would take a bit of mid range out, and probably make the race car slower.