I'm in the process of checking the valve geometry for the new camshaft I fitted. I noticed that the GX valve springs appear to be very close to coil bind. I'm using all stock GX retainers valves dbl springs etc. The valve lift is .435 and at full lift there is .020 between the middle 3 coils (I realize the proper way to measure is with the spring out) , some cam manufacturers spec .050 some .060, I'm likely going to have to measure a spring to be sure but figured I'd check here first................figuring maybe someone knows what the max lift is.

Tom

I have noticed that the clearence between spring retainer to the top of the valve guide [with stem seals] can be an issue as well.

I don't know the answer, but:

* GX camshaft lift is only .311" (cam lift)

* Nissan Competition springs were good for at least .468" and required special retainers.

Quote:

That calcs to ~.445" valve lift. That leaves ~.020 of lift margin. [calculated with a 1.43:1 rocker ratio]

My cam has 298 lift at the cam ,and with stock rockers they were realy close ,so now I'm putting performance dials on ,there designed for large lift cam and are well priced

Got mine through bige

Jesse are you sure that's the lift? Thought you had a bit more than that, or was that the old cam?

The other cam darren wanted me to use had 470 at the lobe ! So yea this one has 426 lift at the valve but still a fair bit of duration

THATS HUGE 470 at the lobe = 672 at valve,THATS THE BIGGEST DATO GRIND I EVEN SEEN,( them springs won't handle that)HAHAAAAAAAAAAAAA. 470 at valve i think.