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Here are the supporting mods, just unsure what to do head wise that's all.

-34 crank

-86.5 pistons

-I-beam rods

-Tomei oil pump

-1.1mm restrictor

-Tomei fuel pump

-gt2860 -5

-Apexi PFC

-Sard 700cc

-Nismo AFMS

-8litre Sump/Baffles

-Greddy oil cooler kit

-Racepace Radiator

-Tomei Type B Camshafts

-Tomei Cam Gears

-Spitfire coil Packs

Cheers.

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Any head is good head. :P

If the valves are seating well you could just do the springs, depending what lift cams you have. I replaced all the exhaust valves in my last head reco (4g63) as I didn't want issues, and they were only $12 each.

Take it to a specialist and ask them what it will cost to reco, they will be able to tell you if the guides need doing etc.

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Im going through the same thing right now. I have some 272 hks cams and im thinking of getting some vavles now to. From your list of mod tje only thing I ant got is that enlarged oil pan.

I got the new head from nissan as well.

Im interested to hear what people will say about this topic because im sorry to say that I never moded a nissan head before and this will be my first time doing it.

interneting.

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I guess the question should be asked. What limits are the stock valves good for??.

Ive seen a 1300hp gtr my RH9 and after his motor failed. It was because the only stock part the guy mentioned thats in his motor was stock exhaust valves, and sad to say he dropped an exhaust vlave. So these valves are good for some high hp levels.

I plan on only 600hp. So im thinking that they should be able to do those levels of hp on oem valves.

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I guess the question should be asked. What limits are the stock valves good for??.

Ive seen a 1300hp gtr my RH9 and after his motor failed. It was because the only stock part the guy mentioned thats in his motor was stock exhaust valves, and sad to say he dropped an exhaust vlave. So these valves are good for some high hp levels.

I plan on only 600hp. So im thinking that they should be able to do those levels of hp on oem valves.

It's not that they are a limiting factor, it's just the valves need to be purchased and seated anyway, so wouldn't imagine the cost would be much more.

bigger valves are usually a good mod for power, not necessary though

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I see your point now. I want to resuse my valves but dont know how to check to see if they are worn. The stem area that is. I have an idea though. The head is new with new seats and guides.

But if I was to get new ones then it would makes sense to go bigger ones, and not oem valves.

One quick questions titanium valves. Whats the hype all about. ???

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I am under the impression it wouldn't be beneficial to have larger valves at all, as the port is still the same size at the seat. It should only be necessary if the seat has been cut back too far. It's also a good way to blow $1000 if you include the Ti retainers...

The Evo head cost me $500 to reco and face, I supplied the valve seals and Tomei springs, they supplied the exhaust valves.

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Lol. I remember seeing that old station wagon in your photo around in some good topics.

Your a smart guy. I agree with you 100%. I really can put that 1k into somthing way better than 1mm oversize valves and having the job done right. Iv see a friend close to me with a v8 motor cut the seats, not replace them. Then he went with bigger vavles. Sad to say one of the seats came loose and fell off.

For a 600hp goal would you recommend the stock valves or do you think after market standard size would do the trick. Any insight would be helpful.

Additionally thanks to everyone on this forum for such insight. To date I have all my rb success do to this site.

Thanks to all.

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I was going to post on this last night (I'm in the US at the moment, so my last night is the same time as MJTru, not the rest of you) but it was well late and I needed sleep.

I would say, stock valves will do. But given that you've got to buy valves (well, at least Fat32gtr does) then you might as well buy some lighter, stronger, nicer aftermarket valves. Or any combination of those things + budget factored in.

If I was to buy non stock valves, then I'd be looking at getting them +1mm and some useful porting in the bowls, turns and decent seat prep to make the most of them. If I wasn't willing to spend the money for that, then I'd just get stockers.

In terms of aftermarket valves available in Australia, I'd probably choose Ferrea, but there's obviously a number of other choices.

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Obviously inconel or titanium valves will handle sustained high temps better than the stock valves, it would really depend what fuel, power and revs you wanted to run, and if you were looking to track it. Things start getting very expensive heading down that road.

I wonder if the Gibson motors ran the stock valves...

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Why not stick with stock valves. They're good to some 800 bhp.

When upgrading valves, it's not just about buying the $3-700 valves but also the labour of installing them. I have a stroker kit and 700whp turbo kit (with many support mods) and stock valves are fine. A stock head can also flow up to 550whp which I've personally seen/driven. If you fried a valve then sure, upgrade but unless you're punching out some serious power and have a good budget, then stay stock. Having bigger valves without other serious mods won't do much I don't think.

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