is it true that if you take a pair of J heads that are 188 intakes, that you dont dont gain much power if you punch them out to 202? do y ou pickup 12-20- HP by doing that??
Not unless you do some work to take advantage of them such as a bowl blend at the least.On a stock head its not woth the effort unless the vlaves are sunk,also as was mentioned its combo specific,for example chevy 1.94 +.100 valves are a great option for alot of engines,it just depends.