my 86 responded really well to a pipe.you can use an 88-04 fmf gnarly, which come in 2 flavours. torque,(low end shunt) and desert(top end). fmf dont list a pipe for the 86 but the later pipes fit, i used a torque and it did exactly what it said on the tin. pro circuit do list an 86 pipe, the platinum, which is a top end pipe, and im gonna be using one as soon as ive finished rebuilding my lump.you can get a choice of reeds for the 86 from boyesen, which again come in 2 flavours, you just have to decide where you want the power in the rev range. the pipe part numbers are;
fmf gnarly torque 020055
fmf gnarly desert 020038
pro circuit platinum pk86500p.
hope this helps, kwakman.