Valve Question.

[Red7m]

I have a question regarding valves. But let me give some info first. I am building my head with a final goal in the 600+hp range. I orginally planed on building the whole motor but it will take to long to get all the parts together and during that time the car would be down. So I just figured I would build the head up and throw in a stock rebuild bottom end I have laying around.

The head has been ported, polished, chambers reshaped and polished, valves unshrouded, 3 angle valve jobed, and surfaced. I have BC stage 3 272/272 cams, bc springs and retainers, ferrea valves locks, and Nippon racing Nitrated valves.

My question is should I stick with the nippon racing valves or should I step up to some Stanless steel valves? What would the benifits of the SS valves vs. the nippon valves if any? After I get around to building the bottom end I plan to rev the motor in the 7.5krpm range and run a gt35 turbo.

john

 

[annoyingrob]

haha, nippon racing. I always laugh at that name

 

[Red7m]

No one?

 

[starscream5000]

Have those valves been proven to last?

I've never heard of them, are they an ebay special?

Sounds like you've got a nice setup going on .

 

[Grimsta]

Titanium valves, yeah baby

 

[bwest]

While I can't say for sure, since I have never done a meteorology test on either of them (only held them in my hands) I can say this:

- The ferrea stainless are significantly lighter (didn't gram scale them, sorry).
- Ferrea's are dished face, nippon are flat - this will affect CC volume as well as the combustion process. How much? never tested back to back and unless you really want to spend the time and money, don't worry about it.
- Ferrea's have a greater margin on the shoulder (read: thicker where it contacts the seat)
- The valve stem is harder on the ferrea's. Running, dual springs the stem literally dented with the nippons. The ferrea's look polished, but no change in shape. I think this has a lot to do with the spring rate as well as the valve material, but just an observation.

 

[Red7m]

Thanks bwest. Also the Nippons that I have are dished. Since I am doing everything else I might as well grab some Brian Crower SS valves as they are only $400.

 

[bwest]

If you 'look' around a little, you can find a set of ferrea's cheaper than that...

 

[AJ'S 88NA]

I have Supertech valves. They are stainless with black nitride coating .5mm oversize. The coating is suppose to make them run cooler.