t5 351 clevo xf ute

[xyef351]

i have a 351 clevo in my xf ute on lpg, and have put a t5 out of a eb 6cyl, works bloody briliant together, my prob is 1st gear is not good, or should i say its great but cant get traction, (heaps of fun but. ) my question is does anyone know if it possible to put a v8 1st gear cog in my box, i6 ratio- 3:50 i think, and v8-2:95. it has 3.08 diff out of ed wagon. thanx all.