Sry my orginal q was about the b16 tb fitting the y8 mani... found that out already. I've been searching for this and I would like to try and get some more opinions about this. Maybe any personal experiences or proven diagrams...
So I have the y8 head complete w ecu. Going on my d15b8. I want to get the most potential gains with this head... it will have a slight mill with a p&p. Between the y8 mani and z6 mani what will gain me well more power... I've come to a slight conclusion that there is not much difference but there still is. Z6 will gain me better top end peak hp while a y8 will gain me more low end... now I would like to know if any can put truth to this using the y8 head... I will be racing this car so high rpm peak hp is more ideal for me, in this case I would go with the z6... thanks much

 

Keep in mind since im racing this car I need to keep it oem. So when i mean most potential with this head is with oem parts/combos. I cant be having an aftermarket skunk mani, if I were to be inspected it would definitely show and result in disqualification. It's a stock class, I/h/e is basically what I can do...