I am installing the Motorsport Electronics Me221 ECU to my blacktop. The instructions shows that it needs a Bosch Wideband Knock Sensor.
Does anyone have the part number for this as there seem to be a few different types.

Hmm
A wideband sensor is a lambda/oxygen sensor that goes in the exhaust system while a knock sensor bolts to the side of the engine block to detect harmful detonation caused by incorrect spark timing, so they are two different things
I would contact ME to find out what they mean by this.

I have an ME221, but 6 years old now so there may have been an update.

However, for wideband you need a controller and sensor, and you connect the controller to the ecu . That is used to give closed loop fuelling control, so the ecu tweaks the amount of fuel to try to keep the AFR correct.

As above, nock sensor is just that, and there is/was one bolted to a zetec I think. Certainly on the ST170. But I have not used it. Lack of knowledge on my part....

I installed a me221 last year.
As cliftyhanger says the wideband lambda needs a separate controller, you can use a narrow band lambda wired straight into the me221.
Motorsport electronics sell all the sensor you need.

It is a knock sensor not a lambda sensor. The one that ME sell is around £85 I was trying to find one of a similar spec

Get one off a zetec or st170?

It's a knock sensor that doesn't have integral filtering (i.e. it gives a frequency response over a large range of frequencies). Many manufacturers use sensors that pre-filter the output for a band of freqs (say 3Khz-6Khz) and if your system requires awareness of sound outside or at the edges of those filters then you can't use them. I don't have a part number, they'll have one they specifically recommend as it will have been their test mule.

Wideband oxy sensor is the exhaust equiv - where it responds over a wider AFR range than a normal narrowband one.