Naturally aspirated performance mods? - Mk1 1.8

Advice on n/a engine performance mods, please.

I have a 1996 Eunos 1.8 (type 2 – 133bhp) – and I have thought long and hard about supercharging and turbocharging, reading a ton of stuff online, and talking to owners and installers.

I’ve decided, for various reasons, not to go down that route – but am still looking to extract a bit more power, ideally in the 3.5 – 6k rpm area.  Not the sort of mental massive hike that forced induction would give me, but enough to be noticeable in spirited road driving.

So a local, very respected MX5 ‘medic’ has said that if they fit new cams (Piper, I believe), that will gain me an extra 12-15 bhp.  If while they’re at it, they skim the head 0.5mm, the upped CR should net another 7 bhp.  Cam work would be around £560, and the head skim £250.  So these combined jobs should net an increase of c. 19-22 bhp, they say – with no ECU change/remap.

A couple of questions (and regardless of the prices compared to forced induction! – I have a budget of up to £1000). 

Most importantly, are these claims realistic?  And if so, would the extra 20-ish BHP be significantly noticeable under hard acceleration/press-on driving?  What could it potentially do to the standard torque curve?

Would it be advisable to have this work done with no changes to the ECU/mapping?  Or could that optimise the mechanical work, and extract a few more horses?

What else could I do to chuck a few more BHP into the mix while I’m at it?  I already have a new Cobalt catback S/S system fitted, plus a pair of new vernier adjustable cam sprockets to dial the cams in spot-on.  Standard airbox/filter etc at the moment – the perceived wisdom seems to be that a free-flow K&N type filter would make little or no difference.

Thoughts please - Thanks!

Steve

Head skim good £ for power as these motors respond well to CR increase without any need for ECU stuff. Not so much BHP but increase in torque.

Have a look at Blink Motor Sport who know what its all about for sure.

I have no connection with them in any way other than the good things ive heard said by the people that race MX5s.

Good Luck with it all