MP62 Notes
Moss Outlet Manifold upgrade for BRP Kits
Long story short, it does not give the 10rwhp as advertised. On the 7th post, the Dyno shows an total increase of 4rwhp on a higher output MP62 setup at around the 230-240 rwhp range. Although the additional power is throughout the rpm range, it basically means the BRP outlet works just fine for most stock to mildly upgraded output levels. To put it in perspective, the 230-240rwhp requires something in the range of 130mm crank pulley. If you do choose to upgrade anyway, note the following issues:
The throttle cable hook will no longer mount flush on the new manifold. A few washers will help this, but it does look a bit "do it yourself" and not a perfect plug and play finish.
The original intake tube that hung off the side of the SC will no longer fit. You'll either need to make some sort of adapter, let it sit in the engine bay, or come up with another mounting solution. Note that it you decide to remove the BRP intake tube, you'll need to figure out how to connect the valve cover hose back into the intake tube.
On a side note, if you do intend to remove the BRP tube and have a way to tap the valve cover's hose to another portion of the intake, Moss has a very nice MAF bracket for only $15 USD that will connect an NB (99-05) Miata's MAF directly to the new outlet. Call MiataMania.com and ask for the 99-05 MAF support bracket, part 052-901. It will connect up the two parts below:
Big Throttle Body Kits
MP62 kits typically include adapters for the following throttle bodies: 1996-2004 Ford 4.6L 2V Mustang
Part #s
BBK 70mm: 1700
BBK 75mm: 1701
Edelbrock 70mm: 3871
Edelbrock 75mm: 3872
Accufab 75mm: F7046
Accufab 75mm: F7546
Edelbrock throttle bodies are preferred, because they have an integrated air bypass screw which may be helpful for hotsides that experience idling issues.