So a good induction kit like the BMC system or another closed cone element would be perfect, if not, then a good panel filter (K&N, pipercross, green filters) alongside a drilled and de-restricted air box and a cold air intake would work well.
Spot on.
For combustion, you want some lairy cams, decent spark plugs, and stuff like porting and polishing.
Lairy cams are a no-go if you keep standard management.
Digifant 3.2 will NOT run anything over about 256s on a standard plenumn...the pulsing in the plenumn causes the MAP sensor to go crazy, ruining the idle and causing uber poor emissions - instant MOT failure.
You can run 268 in/ std ex with good results.
Or you can go standalone management and go 268/268 or higher.
But don't believe anyone who tells you you can fit 268/268 to a standard ECU'd ABF and get it to work...it won't.
Been there, tried that.
Spark plugs will be just fine in an ABF with cams...
Porting and polishing works a treat along with cams swaps...expect around 25BHP geniune BHP from headwork, cam swaps and proper mapping of the Digifant 3.2 ECU.
For exhaust, you want a 4 branch manifold combined with a s/s system.
I'd dissagree there...
4 Branch manifolds crack unless you have very stiff engine mounts...and give no power gains I have ever found.
Standard, ported, is just fine for 200BHP.
SS system makes it sound fast...without it actually making it any faster or more powerful, in my experience...and I've dyno's two of the so called best systems against std.
Throw in a decent remap and you should see something close to 200 horses.
Realistically, I'd expect 185-190 BHP from that lot...maybe mis 190s if you optimise a lot of the smaller stuff too.
200 BHP genuine just isn't going to happen on a standard plenumn, with a standard ECU, in my view.
That barrier needs Jenvey (or otherwise) ITBs to break. I've spent 8 years trying...