Valve Job - worth it?

[elpiar]

Guys,

I'm in the middle of building my motor. My power goal is 350-400whp. The motor is 200k miles. I plan to use GT32 .63 a/r. As far as the head goes. I need to ask few question.

1. 5-angle valve job is $260 additional. Is it worth it? I'm new to nissan and don't know how good of a flow the stock head already have to begin with. 2. Titanium springs/retainers?3. Basic clean up porting? (another $200)

Should I just stick to stock head and basically just refresh it? (seals, etc.)?

[eazye2000]

Dang, that's a heck of a deal for a valve job. Or it is from my experience anyways. For a 3-angle here, my machinist wanted $350. And I would assume for that kind of power, a valve job would be a good idea. Along with getting the guides checked for spec. And depending if you get another cam or not, the factory springs may be worn out and wont do so good on a bigger cam.Just my $.02 and hopefully someone else can chime in on this.

[elpiar]

Dang, that's a heck of a deal for a valve job. Or it is from my experience anyways. For a 3-angle here, my machinist wanted $350. And I would assume for that kind of power, a valve job would be a good idea. Along with getting the guides checked for spec. And depending if you get another cam or not, the factory springs may be worn out and wont do so good on a bigger cam.Just my $.02 and hopefully someone else can chime in on this.

Thanks for the input.

Yea I kinda think it's a good deal. But those additional cost keep going up over my original budget. though it's tough and simplistic to answer, how much hp you think it'll net me with the valve job flow improvement?

[rotorimp]

I would only consider the Titanium bits if your going to be revving the hell out of it. you can have the machine shop test your current springs---but I'm sure they are fine. we are making over 400 with a 3 angle and port matching--with out much effort. spend your money on getting all the rotating parts balanced and good ARP fasteners--if your using the cometic HG then get the head and block mating surfaces perfectly flat (Yes it does matter)

[eazye2000]

.....how much hp you think it'll net me with the valve job flow improvement?

The valve job wont give you anymore flow. It will just keep everything from leaking out of your combustion chamber. It's a good piece of insurance depending on what kind of build you're looking for. If you're replacing everything with stock stuff, then you can probably let the valve job go till later. You can always yank it off while the motor is in the car. But if you will be boosting, and replacing everything with new, forged internals, then I would recommend getting the valves done. If you are looking for flow, have your machinist take the head apart so you can port it out a little bit. Then you can lap the valves in which is not as good as a valve grind/job,but it will be better than just leaving them the way they are at 200k worth of wear.

[elpiar]

I'm replacing with forged internals, build with piston/rods

[Edub1]

I'd deffinitly replace the springs even if just with new stock ones. I doubt I'd pay extra for a 5 angle grind. That price is in addition to the basic grind correct? Porting you can do yourself with a dremmel.

[Kaleo55]

I agree with you all, I would seriously consider replacing the springs after 200k, Supertech or Ferrea. Get the head and block decked.

[Chezedik]

if your using the cometic HG then get the head and block mating surfaces perfectly flat (Yes it does matter)

Hell yes it does, I have one leaking oil for that very reason.

[elpiar]

I'd deffinitly replace the springs even if just with new stock ones. I doubt I'd pay extra for a 5 angle grind. That price is in addition to the basic grind correct? Porting you can do yourself with a dremmel.

No that price is for 5 angle grind. I 'm not sure what you mean by basic grind (3-angle?). Maybe they would lap the valves or the valve seat

[elpiar]

I would only consider the Titanium bits if your going to be revving the hell out of it. you can have the machine shop test your current springs---but I'm sure they are fine. we are making over 400 with a 3 angle and port matching--with out much effort. spend your money on getting all the rotating parts balanced and good ARP fasteners--if your using the cometic HG then get the head and block mating surfaces perfectly flat (Yes it does matter)

Yes, they are going to get the mating surfaces perfect.

I decided to go with stock cams and just basic maintenance rebuild on the head. what do you guys think?

BTW do people change cam bearings for rebuiding?

[Chezedik]

You need to get at least a three angle job, and then I would go with the V2 or V3 cams.

There are no cam bearings in the KA.