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Hey guys, I lurk here often and post rarely, but thought i'd see what ideas and advice you have for me with my current project. I've got a 91 NA6 with a ported and cammed b6 in it, and i'm looking to give it a little more overall hump across the rev range...

I had considered going down the turbo route, but I like the power delivery of the 1.6 and didn't want to ruin it's dynamics too much. Soooo after lots of hunting and looking at various options i've bought an SC14 toyo supercharger off a 1ggze (2litre 6cyl) and plan to run it at around 10-12psi.. (infact out of pure awesomeness it was delivered to the door while posting this)

The plan is to run it hotside down around where the aircon once resided.. through a 7mgte intercooler (small, and efficient enough) and then to the Throttlebody/inlet manifold..

I've bought a Microtech Lt8 for tuning and to get rid of the afm to simplify things.

Any idea how much fuel I MIGHT neeed... ie. Will the 1.8litre injectors give me enough fuel???

Anything else i should be aware of?

Oh and sorry mods, looks like I might've posted this in the wrong sub-forum, if you want to move it no dramas!

1.8 injectors will be a tight fit if you're not using an AFPR (Adjustable Fuel Pressure Regulator).
The safest boost I would run with those is 6-7psi as they are hitting 85% duty at those levels in the upper rev range. I'm using Mazda 323 GTX injectors and they're not hard to tune and run, just safe for 12psi.

Drop in replacements are easy to obtain from other models and will work well with the standard fuel rail pressure. Have a look at this list here.

Your hardest part of the mod to supercharger will be regulating your idle as the mx5 IAC is on the throttle body (which needs to be relocated pre supercharger for better control). I've used a bosch IAC from a hyundai excel with good results, tapped into the IM chamber.

Tapping the IM isn't too hard (compared to making all the brackets to fit the SC unit in the first placE).

Good Luck

I lined up 4 550cc injectors today, so fuel is sorted. (have bosche pump)

Looking at the supercharger i don't think it's going to be tooo difficult. I'm going to set my spare engine up on the back patio and make up a few cardboard templates, then weld it all together in metal bits there..

I was still going to run the standard throttle body location and use a ercirculating bypass valve that operates under vacuum to cover the idle side of things..

What i'm worried about is the lack of top end people keep telling me about, how do you find yours?

My top end is fine thanks... I'm turboed
The Toyo s/c setup went on a mini.
With boost and the weight of the mx5, you really don't have much time to worry about the top end of the rev range, at least not in the lower gears.