Apologies for what must be the 1000th question on the subject - I've searched but can't find an answer for the exact combination of Z4 + 3" decat.

Having fitted an STI Z4 ecu and full 3" decat to my 1993 WRX I've decided to leave the power as is, and just enjoy it as a fun, capable road car.

The car is otherwise original - even down to the 112mph limiter. I've been watching the boost gauge and it only overboosts very slightly (1-1.5psi) in 5th. But, given the speed limiter and my awareness of the issue, it rares sees WOT in 5th for more than a few seconds.

It never bangs, except for the odd bang when changing 2nd-3rd at 3.5-4k rpm pulling away after a good run (I think due to momentary overfuelling 'thanks' to the dump valve which I'm replacing with a standard recirc). This worries me - should it not be popping more if the fuelling was safe?

Next on the shopping list is a wideband AFR gauge and (maybe) a 190lph fuel pump for piece of mind.

So, the age-old question: am I safe to use it without a remap?

I'm reluctant to cross that bridge, because then I 'may as well' get a FMIC/FPR/440cc/etc. and suddenly the c.£650 remap costs a lot more!

Thanks in advance!