header tube size

[10 '' outlaw]

Need help with header size i have a 565 bbc in 3400 # car motor should make about 970 hp I have a set of lemons 2 1/8 - 2 1/4 stepped headers with a 4 '' merge collector i think it may need 2 1/4 straight or 2 1/4 - 2 3/8 stepped some power gained on dyno with bigger headers may not translate at track in heavy car thanks outlaw