I need some help again

, I think my clutch might be slipping as I felt the revs surge when I put my foot down on the A1 last ( I hope it might be wheelspin but I think its unlikely as i was in 5th gear doing 80 mph

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I'm on a tight budget so I used my old silvia pressure plate and a new 9" friction plate from a 200sx from Nissan. I'm thinking old clutch cover wont be strong enough , does anyone know if these should work together ok. Cheers