rb25det internalls? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

ricardo.benin · 10-20-2014, 11:16 PM

Hi I have a rb25 and I am going to put weisco pistons as well as eagle or brian crower rods. So my question is this I am going to have the cylinder head reconditioned so what can I get away with with the stock head do I need springs and retainers if so can I just put stiffer springs and reuse the stock retainers also will the stock cam and valves handle the power, one guy was saying to install bigger exhaust valves. I know there is a lot of info on what oil mods to do and not to do but I am trying to find out exactly what I need as this engine is going to be in a street car. I did not want to block off oil or add restrictors as I am going to use hydraulic lifters and they are oil thirsty but I was thinking of adding a line from back of head to sump so the oil can drain quickly. Also should I stick with the 9/1 compression.
Any info on how to pursue this build would be greatly appreciated.
Thanks
Richard

_ivn13 · 10-22-2014, 08:58 PM

[QUOTE=ricardo.benin;5748268]Hi I have a rb25 and I am going to put weisco pistons as well as eagle or brian crower rods. So my question is this I am going to have the cylinder head reconditioned so what can I get away with with the stock head do I need springs and retainers if so can I just put stiffer springs and reuse the stock retainers also will the stock cam and valves handle the power, one guy was saying to install bigger exhaust valves. I know there is a lot of info on what oil mods to do and not to do but I am trying to find out exactly what I need as this engine is going to be in a street car. I did not want to block off oil or add restrictors as I am going to use hydraulic lifters and they are oil thirsty but I was thinking of adding a line from back of head to sump so the oil can drain quickly. Also should I stick with the 9/1 compression.
Any info on how to pursue this build would be greatly appreciated.
Thanks
Richard[/QUOTE

Im not a rb specialized but i do know how dyno sheets look when you have block work but not head work you'll make good power because your able to raise your boost but at top end you'll feel like you dont gain more power more like it reaches a limit and stops. i wouldn't reuse stock retainers with upgraded valve springs just because those retainers are made for how stiff that stock spring is. dont know about the whole sump thing never have heard of that. and yes if its a street car 9:1 is fine

10-20-2014, 11:16 PM	#1
ricardo.benin Leaky Injector Join Date: Dec 2012 Location: us Posts: 70 Trader Rating: (0) Feedback Score: 0 reviews	rb25det internalls? Hi I have a rb25 and I am going to put weisco pistons as well as eagle or brian crower rods. So my question is this I am going to have the cylinder head reconditioned so what can I get away with with the stock head do I need springs and retainers if so can I just put stiffer springs and reuse the stock retainers also will the stock cam and valves handle the power, one guy was saying to install bigger exhaust valves. I know there is a lot of info on what oil mods to do and not to do but I am trying to find out exactly what I need as this engine is going to be in a street car. I did not want to block off oil or add restrictors as I am going to use hydraulic lifters and they are oil thirsty but I was thinking of adding a line from back of head to sump so the oil can drain quickly. Also should I stick with the 9/1 compression. Any info on how to pursue this build would be greatly appreciated. Thanks Richard

10-22-2014, 08:58 PM	#2
_ivn13 Join Date: Oct 2014 Location: Whittier, CA Posts: 9 Trader Rating: (0) Feedback Score: 0 reviews	[QUOTE=ricardo.benin;5748268]Hi I have a rb25 and I am going to put weisco pistons as well as eagle or brian crower rods. So my question is this I am going to have the cylinder head reconditioned so what can I get away with with the stock head do I need springs and retainers if so can I just put stiffer springs and reuse the stock retainers also will the stock cam and valves handle the power, one guy was saying to install bigger exhaust valves. I know there is a lot of info on what oil mods to do and not to do but I am trying to find out exactly what I need as this engine is going to be in a street car. I did not want to block off oil or add restrictors as I am going to use hydraulic lifters and they are oil thirsty but I was thinking of adding a line from back of head to sump so the oil can drain quickly. Also should I stick with the 9/1 compression. Any info on how to pursue this build would be greatly appreciated. Thanks Richard[/QUOTE Im not a rb specialized but i do know how dyno sheets look when you have block work but not head work you'll make good power because your able to raise your boost but at top end you'll feel like you dont gain more power more like it reaches a limit and stops. i wouldn't reuse stock retainers with upgraded valve springs just because those retainers are made for how stiff that stock spring is. dont know about the whole sump thing never have heard of that. and yes if its a street car 9:1 is fine