Thread: 20VE vs N1 vs 20V spring pressures

All data based on FSM values.

20VE/16VE
Valve closed (seat pressure): 64 lbs
Valve open at 12mm (open pressure): 145 lbs

N1
Valve closed (seat pressure): 45 lbs
Valve open at 12mm (open pressure): 150 lbs

20V
Valve closed (seat pressure): 47 lbs
Valve open at 12mm (open pressure): 158 lbs

Interesting thing, with more lift 20V springs and even N1 springs
are stiffer than usual 20VE springs. What do you guys think of this?

wow this does not seem like a lot of spring pressure at all. (do all this cams have the same base circle just wondering)with more lift you usually want more spring pressure also depending on what rpm you are running and how much weight the spring has to control.also take into consideration the weight of the spring its self.(also i am used to chevy engines maybe thats why this does not seem like a lot of pressure)do u no the weight of retainers and keeps good info by the way

20V spring weight is 50 grams. I didn't measured 20VE or 16VE ones.

great info for the forum.

There is nothing intresting about the spring presure being more with the higher lift cams. That how it should be, higher lift, higher open spring presure.

now that we have the info on stock what are the rates of the aftermarket springs? also why do the n1's have a lower seat pressure than the others?

so does that mean my stock 20ve springs wont float at 9000rpm (with n1 cams installed)?

The N1 Valve stems are narrower, i would say this is for protection of the valve and reducing stess on it.

are the n1 valves also longer?

The n1 valves are the same thickness. Nissan designed the springs with less closed seat presure to maximise hp. This happens because there will be less friction on the cams, less friction makes it easier to turn the motor which means less work for the motor whi h means more hp to the flywheel.

I got different numbers for the 20VE/16VE and N1, also straight from the FSM.

20VE/16VE
Seat pressure: 60-68 lbs
Open pressure: 138.22-152.61 lbs

N1
Seat pressure: 43.55-46.34 lbs
Open pressure: 140.76-149.44 lbs

I think you forgot to add the inner spring pressure.