Increase FPS count on oculus rift VR

I am a beginner who have been working on unreal engine VR development project for recent months.I have been assigned to do increase the fps count,and graphic profiling stuff.I had a pretty much time with that optimization part also went through the every optimization information,but i was unable to increase the fps count to (90 fps) on oculus rift.The project has got many detailed textured 3d models and entire project cost around 58 gb on unreal editor.Please anyone can help help me to figure out this thing?It would be really helpful to me.

Sorry to say, but your request is so generic that it is very difficult for anyone to give you specific recommendations, including myself. So here are some generic ones.

At high level, you have to understand if your FPS are being limited by the CPU, by the GPU or by both of them (CPU-bound, GPU-bound or CPU+GPU-bound). Once you have figured it out, you can start profiling more in details and addressing the elements having the highest impact on the frame rate.

This is the official documentation on profiling: Performance and Profiling | Unreal Engine Documentation

There is a set of performance recommendations and settings specifically for VR, you can find them here:
and here:

This is also a useful source of information:

With VR you definitely want to use the Forward Renderer and, even if this is somehow controversial, Instanced Stereo. Depending on your application, you may want to turn off the most expensive Post Processing features.

Also have a look at these two videos: Robo Recall Performance Optimization | Project Spotlight | Unreal Engine - YouTube and Oculus Connect 4 | The Road to Shipping: Technical Postmortem for Robo Recall - YouTube
They go over many optimization tricks that were used with Robo Recall.

Hope this helps!

Someone gave me the suggestion to download Epics Robo Recall mod project package, inspect it and compare to your own project the various stats and asset complexities.
This was a great idea and I am using some of what I found to limit my own game with. Of course it all depends though.