As the power-making capabilities of the VR38 continue to increase, the need to provide a proper fuel delivery solution for the GTR has become a necessity. After months of research and development, designing and refining, testing and verifying, the T1 R35 GTR Fuel Rail Kits are finally available for release.
One of the objectives we were looking to accomplish during the design phase of the T1 GTR Fuel Rail Kit was to keep things simple, which does not always equate to 'easy'. When testing multiple designs, we decided that any fuel rail solution that requires secondary mounting brackets or adapters for the factory pulsation damper or factory fuel pressure regulator would require a compromise that we were not willing to make. While these types of compromises would have made the manufacturing process simpler and less-expensive, we were more concerned with doing things the right way, not the easiest way.
One of the issues we encountered when considering secondary mounting brackets was the type of load the fuel rails will see during use. The GTR runs a differential fuel pressure of 50psi. Based on the surface area at the inlet of the injector, this equates to roughly 12 pounds of force literally trying to push each injector out of the rail. This translates to 36 pounds of force trying to separate the injectors from the rail, which puts a significant load on the fuel rail mounts. We were definitely not comfortable with the potential for the fuel rail mounting brackets to flex under load and compromise the alignment of the rails (and more importantly) the sealing properties of the injectors. And we all know that fuel leaking in close proximity to hot surfaces could lead to a GTR-B-Q of epic proportions, which we are not a fan of here at T1 (...we do love barbeque, however). So we decided on a 1-piece billet design. No secondary mounting brackets necessary. For the sake of simplicity, we also decided to retain the factory mounting method and location for the pulsation damper and the fuel pressure regulator. No adapters or additional fittings required.
Fuel temperature is another issue that is often overlooked. Since the VR38 generates plenty of power, and a byproduct of power is heat, the cylinder heads transfer and retain a generous amount of heat. Some of this heat gets transferred from the heads, to the fuel rails, and subsequently to the fuel itself. Once fuel reaches it's boiling point, it will begin to cavitate at the pump, which will then cause fuel pressure to fluctuate unpredictably. We've incorporated 1/4" phenolic spacers between the heads and fuel rails to alleviate this issue. Phenolic has excellent insulation properties, and will keep as much heat out of the fuel rails as possible.
To connect the two fuel rails we opted for Goodridge's 'G Line XF' hose, which is the company's premium line. This hose is constructed of super-light Aramid braid (which provides excellent durability), with a PTFE inner bore which is smooth inside (for increased flow), and is convoluted (for amazing flexibility). The hose is fully compatible with all fuels, including race gas, E85, and methanol. The lightweight crimp on hose ends ensure a leak-free seal and light weight.
Our kit was designed to be used in conjunction with our entire line of ID fuel injectors, which will provide your GTR with the best, most accurate fuel injectors available. (Your tuner will thank you!) The injectors are available in 725cc, 850cc, 1000cc, and 2000cc sizes depending on your fueling needs. Give us a call for guidance regarding injector sizing, or check out the Injector Calculator on the Injector Dynamics website.
The T1 R35 GTR Fuel Rail Kit comes complete with 2 black anodized billet aluminum fuel rails, all necessary Goodridge black anodized fittings and hose, stainless-steel mounting hardware, and phenolic spacers.
So if you're looking to address your fuel system needs, our advice is to do it once, and do it right...and this will be the only solution that your GTR needs.