Does the combination of the following mods require a remap ECU to ensure reliability?

Mazda Efini JDM Y-Pipe
Peter Farrell Supercars 3" Stainless Steel Downpipe
Koyo 2" All Aluminum Radiator
HKS Exhaust
HKS Blow Off Valve

 

Depends. If your boost is creeping or spiking past 10 - 11 PSI, then yes. The DP and exhaust are what will do it.

 

would the M2 remapped ECU be a good choice?

 

If you're spking over 10#'s get some kind of boost controller and call it a day. You can go basic for under $20 or electronic such as Profec B for around $200. When you move up the mods get the M2. BUT, ECU's or boost controllers wont work if you're getting creep.

 

No need for an ecu, at all. Keep your boost at 10psi and you will still be running pretty pig rich. The 3-mod-rule has been proven to be pretty BS. You don't really have any flow mods, since you still have a restrictive intake (box/duct/filter/IC) and exhaust (cat-back/main-cat). Even if you did get an intake and cat-back, you will still be rich(not in funds, but in air/fuel ratios).
http://www.wvinter.net/~flanham/wlan.../3modrule.html (informative link)

 

So if you have boost creep getting a boost controller wont help this problem?

 

Nope -- the wastegate would need to be enlarged.

 

if you enlarge the wastegate...will the wastegate door still be big enough to close it off?

 

You port it so there is still some edge left to close off!

 

hey my name is stupid what's yours? lol