Sarah Forst posted on January 26, 2009 12:00
Are there any aftermarket turbo kits available for the VQ37VHR?
Jorge Medina
Corona, CA
It's no small feat trying to assemble a turbo kit for an engine with a high 11.0:1 compression ratio, but you are in luck. Although other companies are working on putting together a forced induction product, GTM is the only one that currently offers a complete turbo kit for the VQ37VHR- a twin turbo kit that includes everything you need to get boosted from the Garrett ball bearing water and oil cooled turbochargers to a bar and plate intercooler rated up to 1000 horsepower. There are a few turbo options for this kit- a GT28RS turbo with 0.64 A/R for a potential 500 horsepower or 0.86 A/R for up to 700 horsepower, or the GT3071 with 0.64 A/R for an estimated 900 horsepower or 0.86 A/R for around 1000 horsepower. While the block, rods, and crankshaft seem to support over 10 psi, the stock pistons are a somewhat weak design and any of the larger turbo kits or too much boost may push them to a point of failure. It is also unlikely any turbo system for these engines will pass CARB certification. JWT tried unsuccessfully to get their TT kit for the VQ35 CARB certified and the cost to attempt a CARB certification is not usually justifiable by most tuner shops.
Due to the trickiness involved in tuning the VVEL, there are few engine management options available. While the factory ECU may work for low boost levels, GTM is testing the kit using an HKS FCon VPro standalone. You could also go with a Technosquare reflash or the Haltech plug and play engine management system depending on your horsepower goals. Since the car was tuned for a naturally aspirated program, you will most likely max out the MAF at more than 8 psi. The VQ37VHR is also an open deck motor which helps control top cylinder temperatures for fewer hydrocarbon emissions, better ring seal, and less bore distortion, but a closed deck motor is usually the preferred design for forced induction. However, boosted VQ35 engines did withstand 700 whp even with an open deck and aftermarket buttressed sleeves may help prevent any issues with these kits teetering on close to 1000 hp.
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