I had a TF135 with 142bhp - just a backbox and an induction kit. 0-60 was actually pretty good at that, with the car hitting 60mph in about 7.5 seconds (so just off a normal VVC F). It was timed about 7.3 on a rolling road, no drag forces however. I suspect that a remap would have hit 150bhp ish and put the car around the 7.0s 0mph to 60mph area.
That said, your NOT going to get to 160bhp with just bolt ons and a remap.
You CAN get a 135 upto 160 - I was going to do it before selling my TF and buyig Panther. The issue is getting hold of a VVC head. Now, im pretty sure, that if you got a VVC head, a blanking kit and a set of cams youd be able to bolt that on without change anything on the wiring loom side - as your not using a VVC mechanism.
To convert to a full VVC (which would be cheaper probably) youd need the head, loom and all sorts of other electrical gubbins.
Youd then have a car producing about 175bhp+ once remapped - and you'd keep the 135 driving characteristics due to the power delivery being very similar.
Issue then is that the standard 135 internals start to redline about that sort of power.
Id recommend keeping an eye out for a scrapped 160 and try and get the engine, loom, ecu, fobs, alarm and the coils all in one go, that way you can just bolt off one subframe with your old engine and bolt in the 160 one. You could then sell on the 135 engine.
Id really recommend however that you look at selling your 135 ( a few months back id have not agreed with this). Unless your car is already modified with a few bolt ons, or its in exceptional condition it would be far cheaper and easier to just got to a 160.
Otherwise, if your car is already modded, you could ask to go for a spin in a members car thats been remapped. Apparently the difference is striking and comes highly recommended from most members who have had it done by ZandF.