Question is why. Other than gaining an extra gear, there is a lot to consider
VQ transmission swap points to consider
1. speed sensor, there isn't one. VQ's get speed out of the diff
2. Adapting, usually required adapting a RB bell housing to an adpater to the VQ tranny
3. Gearing. First three gears are pretty short (dialed in for 3.5 rear). So spinning in first three gears is pretty easy.
RB25 tranny's are very stout
RB25 transmission, less headache, less work, less hassle and totally strong.
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