What's GTM got up their sleeve?

Scribe

I wanted to join in and commend GTM for their contributions to the Z34 platform. Coming from a long DSM background (no laughing), I'm personally very excited about this latest kit.

This kit sounds like it is a better match for the stock VQ37 for a daily driver on stock internals than any other kit out there. The size of the turbos, intercoolers and piping size will lend itself to faster spooling. At the same time, these turbos should also be capable of easily keeping up with the demands of 1.85 (half of 3.7) liters at the lower boost levels that are supported by the stock internals and high compression. As Big T pointed out, the 20G is actually large enough to flow enough air to supply over 20 psi to a 2 liter at 7K on the old 4G63. The V37Q, as Mike pointed out is a very different animal. In theory, a 16G is sufficient to meet the CFM demands of each cylinder bank at lower psi levels, such as 8.5 psi. I'm very curious to see how the pairing works in application.

For those concerned about the intercoolers ability to cool the intake charge, there are two things to consider. First, the air is not being super-compressed at the levels of boost we are talking about. Second, air-to-air intercoolers work off of temperature differential. As ambient air (outside the intercooler) passes through the fins of an intercooler and carry away the heat, that air is heated. The ability to carry away heat is diminished fairly significantly after about 1.75" (if I remember from either Bell or Coleman's writings). Air that passes through (inside) the rear of thick intercoolers does not experience nearly as large of a cooling effect. That said, GTM managed to stick a 2.5" intercooler between the crash bar and the radiator in their supercharger kit.

I also like the idea of keeping the crash bar on the front. In the event of a low speed impact, there would be no damage to the intercoolers; and the front tow hook will remain accessible should you ever need to use it.

On top of all that, making this kit more affordable is a significant plus.