VQ30DETT engine swap?

[fairlady_z350]

The 350z's or the Fairlady Z's in the JGTC 500 class have all swapped their engines from the VQ35DE to the lower displacement VQ30DETT. I was wondering why they are doing this and what benefits they are getting out of it? I read in another thread that this engine comes from the Gloria or the Cima. Would this be a good engine to bring to swap into a stock 350? Or is there not really any point.

[VQuick]

There is no production VQ30DETT. The closest is a VQ30DET from the Cedric/Gloria and Cima. It's rated at 276hp, but of course the VQ25DET has the same rating. The 3L is probably making up to 300hp, if not more.

Tunability should be okay. Although it sounds similar to the US-spec VQ30DE, it has more boost-friendly 9:1 pistons rather than 10:1. There are US VQ30DEs with turbo kits making 500hp with just additional fuel and careful tuning. Increasing boost on the turbo motor shouldn't be a problem.

The advantage of the 3L turbo is that it's built for boost, vs the 3.5L. You won't have to be quite as careful.

If you want one, I'd suggest asking different engine importers. The VQs aren't that popular compared to the RBs, so you might have a hard time finding one. They're out there, though.

[JCCR]

why would you want to swap out a new engine when all you can do is tubocharge it.

i think nissan could of easily tune the vq35de to make atleast 350hp in stock form therefore the 300zxtt is a better car cuase its easier to get more power.

[VQuick]

Originally Posted by JCCR

why would you want to swap out a new engine when all you can do is tubocharge it.

The VQ30s have a shorter stroke than the VQ35s, which allows them to run smoother. They can also rev higher. The turbo version in question here is already built for forced induction and, depending on who you got it from, would include most if not all of the turbo hardware needed.

The VQ35 can be turbocharged, but at a cost significantly higher than just getting the VQ30DET. Most kits alone(not including installation and tuning it just to run correctly) would probably cost more than swapping the 3L in and tuning it for even more power. The VQ35 also isn't as boost friendly, with its 10.3:1 compression ratio. Careful tuning will be needed. With the VQ30DET, compression is already 9:1, and offers more leeway with tuning.

i think nissan could of easily tune the vq35de to make atleast 350hp in stock form therefore the 300zxtt is a better car cuase its easier to get more power.

The limit of the VQ35DE in street legal form(passes emissions, etc) is supposed to be about 310hp. There are full race normally aspirated VQ35s producing 450hp, however.

The Z32 is heavier, and was more expensive. Its handling is also not as balanced as the Z33's. A Z33 could have a slight horsepower deficit and possibly be just as fast, if not faster, on a course than a Z32. If they had equal power, the Z33 would probably have the advantage.