R34 Rb25 Neo Valvesprings And Hardware?

[GTR_JOEY]

Revs, PSI and cam profile are the three biggest/ if the only factors when considering valve spring upgrade

I don't see how power makes a difference

Generally Jap and standard cams have a pussy profile so a stronger spring is less required

[GTSBoy]

I don't see how power makes a difference

Well, I guess that most other things being approximately equal (unless you have a seriously developed head and unusual cams etc) then power and boost more or less scale together for a given type of engine.

[Piggaz]

Yeah but 20 PSI on a stock turbo isn't going to make the same power as something three times the size.

[GTSBoy]

I realise that......but FWIW, most people intent on running 20 psi put on a turbo big enough to do 20 psi at the best flow/most response they can get. People wanting to make more power will put on a turbo able to do 30 psi at the best flow/most response they can get at that level. etc. Doesn't matter if it's a HG highflow, HG replacement, Garret GT/X, Holset, whatever. At any given power level, the most appropriate current turbos (let's ignore old tech turbos) from different sources are all approximately the same thing. If you stray off that line then you're choosing something that is either being run below its best boost for the flow or below its best flow for the boost.

Edited February 15, 2015 by GTSBoy

[r32-25t]

What you just said has no relevance to what this thread is even talking about

[Piggaz]

Next we will be dragging out compressor maps to see where our valves will float.

The point is, power itself doesn't influence where or when this issue will arise.

Boost, revs and ramp rate of the cams are it. If the engine makes 200 hp at 15 psi at 6500 rpm and it floats, why would it float earlier with 600 hp at 15 psi at 6500 rpm?

[GTSBoy]

I don't think anybody has said that. I think you're just choosing to misunderstand a poorly phrased statement.

[lcxu105]

Dose anyone know the part number for the 25 neo supertech valve springs?

[lcxu105]

Just spoke with supertech and they don't do spings for the neo head.

[GTR_JOEY]

Look up Ferrea if your willing to spend the cash on a good product

[GTSBoy]

^ Probably the most solid thing said in this thread to date.

[Huzqld]

Performance valve springs. Do a spring and ti retainer set for the Neo. Don't know how good they are but I'm running a set and I know that's what john from nextup with the 700+hp Neo had in his with big cams and he had no issues

[lcxu105]

Yer I got a price on them today. Fairly cheap and they are only a single spring not duel. Ferrea do a duel spring but are very expensive.

[AngryRB]

At what point is it necessary to upgrade the cam bolts? will they be fine with say 260 poncams and stiffer springs?

Edited September 7, 2015 by AngryRB

[iruvyouskyrine]

Cam cap bolts? I'm gonna say almost never. That's just my opinion.

[RRob]

Its not only the inlet valves that see boost pressure. Exhaust manifold pressure is similar to inlet pressure.

[AngryRB]

so apart from valve float, is there a notable performance difference between say a stock spring and a performance spring?

[GTSBoy]

There's something valve springs are supposed to do other than keep the valve on the seat and in contact with the lifter?

[CHRIS MW33]

hey any updates on this topic? how have the Performance Valve Springs held up over time for the rb25det neo? also any other spring manufactures other than ferrea trusted for the NEO?

[34GeeTeeTee]

7 hours ago, CHRIS MW33 said:

hey any updates on this topic? how have the Performance Valve Springs held up over time for the rb25det neo? also any other spring manufactures other than ferrea trusted for the NEO?

Mine have been in for 6-7 years with the car doing around 15-20 track days a year on top of many KMs of street driving before it was made into a dedicated track car.

Never missed a beat with the Performance Valve Springs! Good gear