Wait for it......another "what will it make?"

Mal, there's a guy in Adelaide here that just had his 408 on an engine dyno, while on the dyno they swapped between a set of tri-y's and a set of morphett's 1.75" 4 into 1's. the result was around 3or 4 HP gain right at the top end with the 4 into 1's, so spend elswhere!