Hello, I’m new to forums so I may be posting in the wrong place but here we go,
I am seeking advice on a 08’ Nissan Skyline 370GT SP 6MT Coupe (RHD) which has roughly 60,000 miles on it. It’s basically a Japan spec G37, I don’t know the closest Infiniti variant but it has 4WAS. It should have VLSD, and I recently purchased Pirelli tires. I am also about to install a Z-Speed heavy duty CSC with a stage 3 clutch. I’ve done a good amount of research through the forums but lots of threads are a decade old and may have outdated info.

My goal is to achieve around 550 WHP with the option to increase capacity later on to like 800 if it seems reasonable (lol). I am considering installing forged internals. However, I am unsure about what products to use. The Wiseco Piston Eagle kit is one option that I've come across, but I'm uncertain if it is a good choice or if forged internals are necessary for this level of power given my car's current mileage. I understand the 6MT transmission is pretty bulletproof so I’m hoping I won’t have to swap that out.

I am looking at installing 1300cc fuel injectors, a Warlbro 525 pump hardwired to the battery, and a CJM Fuel Return System. At the moment, I'm not too focused on the turbo kit (though I'm leaning towards a twin, possibly from AAM), as my main concern atm is to get the car prepared to handle it later on.

I’m relatively new to car builds, and am unsure if I am overlooking any crucial aspects. The stock brakes have been great so far, but I’m not opposed to beefing them up if required. I’m still rocking the stock sport exhaust and just about everything else is stock. My goal is reliability, as I intend to use this car as a daily driver. While I'm aware this won’t be cheap, I got the car at a great price and it looks like a solid platform to build on with great returns. Any advice or wisdom would be greatly appreciated, even if it means looking at other cars.

 

Hey Dan, welcome to the forum. In the States that power goal has been proven left and right to be realistic and pretty reliable as well as long as the tuning can back it up.
It's not power that blows the 3.7 but the insane torque that it can produce on certain turbo setups. Most of this come from a big single turbo that moves the power band higher towards VVEL activation.

So with this suggestion a twin turbo kit similar to OEM GTR or GTR upgraded can produce some good power especially down low without too much sacrifice.

As far as the building of the engine, it's a bit tough. It's not until you build one that you realize that Nissan/Infiniti did an amazing job from the factory. Many times folks who get them built go with a smaller compression forged piston only to loose power because they're not pushing the power that a lower compression piston would shine on. It's been proven that the 11:1 OEM ratio is perfect for boost and even better on ethanol or other exotic fuels.

In reality you could push the that block to 600-700whp with the right fuels unopened. I suggest you skip the building aspect of it and get you later on a newer 2013+ motor as a spare and build which ever fails.
Most folks including myself looked a building anything over 500whp however time and wisdom have shown that certain specific engines from factory bring a great combination with an ideal piston ring clearance to accept both turbo or all motor.

FYI you'll destroy the OEM VLSD even in oem trim. For the OEM engine a set of new gallery gaskets and or chain guides will freshen that side up and prevent you from failing from leaking oil pressure to your VTC which is common from 09-2011.

Im part of the 4WAS crew as well. Good luck.