Distortion of the Quran by the Raafidis
Question

I have also heard by a shia collegue that their is a surat in their book which is not in the QURAN. can u confirm this? the surat in qs is called SURAT AL-WILAYAT.
Praise be to Allah.With regard to Soorat al-Wilaayah, some of the Shi’ah scholars and imams have stated that it exists. Any of them who denies that does so by way of taqiyah (dissimulation). One of those who clearly stated that it exists is Mirza Hussein Muhammad Taqiy al-Noori al-Tubrusi (d. 1320 AH). He wrote a book in which he claimed that the Quran had been distorted and that the Sahaabah has concealed some parts of it, including Soorat al-Wilaayah. The Raafidis honoured him after his death by burying him in al-Najaf. This book by al-Tubrusi was published in Iran in 1298 AH, and when it was published there was a great deal of controversy because they wanted the doubts about the validity of the Quran, which were known only to their leaders, to remain scattered throughout hundreds of their major books, and they did not want that to be compiled in one book. At the beginning of his book he said:  
“This is a good and noble book entitled Fasl al-khitaab fi ithbaat tahreef Kitaab Rabb il-Arbaab (Decisive comment on the distortion of the Book of the Lord of Lords)… He mentioned aayahs and soorahs which he claims that the Sahaabah concealed, including ‘Soorat al-Wilaayah,’” the text of which, according to them, and as quoted in this book, is: 
“O you who believe, believe in the Prophet and the Wali [i.e., ‘Ali] whom We have sent to guide you to the straight path, a Prophet and a Wali who are part of one another, and I am the All-Knowing, All-Aware…”  
And they have another soorah which they call Soorat al-Noorayn: “O you who believe, believe in the two lights (al-noorayn) which We have sent down to you to recite to you My Verses and to warn you of the punishment of a great Day. They are part of one another and I am the All-Hearing, All-Knowing. Those who fulfil the covenant with Allah and His Messenger mentioned in the verses (of the Quran), the Gardens of delight will be theirs, but those who disbelieve after they believed by breaking their covenant and disobeying the command of the Prophet, they will be thrown into Hell. They have wronged themselves and gone against the wasiyyah of the Prophet (i.e., the appointment of ‘Ali as khaleefah), and they will be given to drink of boiling water…” and other such nonsense. 
Prof. Muhammad ‘Ali Sa’oodi – who was one of the greatest experts of the Ministry of Justice in Egypt – examined an Iranian mus-haf kept by the Orientalist Bryan and he obtained a copy of this soorah; above the lines of Arabic script there is written the translation in the Iranian language. 
As it was mentioned by al-Tubrusi in his book, Fasl al-khitaab fi ithbaat tahreef Kitaab Rabb il-Arbaab, it is also mentioned in their book Dabastan Madhaahib, which is in Farsi, written by Muhsin Faani al-Kashmiri. This book has been printed numerous times in Iran, and this false soorah was quoted from it by the Orientalist Noeldeke in his book The History of Qur’anic Manuscripts, 2/120, and was published by the French Asian newspaper in 1842 (p. 431-439). 
It was also mentioned by Mirza Habibullaah al-Haashimi al-Kho’i in his book Manhaaj al-Baraa’ah fi Sharh Nahj al-Balaaghah (2/217); and by Muhammad Baaqir al-Majlisi in his book Tadhkirat al-A’immah (p. 19, 20) in Farsi, (published by) Manshoorat Mawlana, Iran. 
See also al-Khutoot al-‘Areedah li’l-Asas allati qaama ‘alayha deen al-Shi’ah by Muhibb al-Deen al-Khateeb. 
This claim of theirs is a denial of the words of Allah (interpretation of the meaning): 
“Verily, We, it is We Who have sent down the Dhikr (i.e. the Quran) and surely, We will guard it (from corruption)”
[al-Hijr 15:9]
Hence the Muslims are unanimously agreed that anyone who claims that anything in the Quran has been altered or changed is a kaafir. 
Shaykh al-Islam Ibn Taymiyah said: 
The same applies to those among them who claim that some verses of the Quran have been taken away or concealed, or who claim to have some esoteric interpretations that exempt him from having to do the actions prescribed in sharee’ah etc., who are called al-Qaraamitah and al-Baatiniyyah, and who include al-Tanaasukhiyyah [names of esoteric sects]. There is no dispute that they are kaafirs. 
Al-Saarim al-Maslool, 3/1108-1110. 
Ibn Hazm said: 
The view that the Quran has been altered is blatant kufr and is a rejection of what the Messenger of Allah (peace and blessings of Allah be upon him) said. 
Al-Fasl fi’l-Ahwa’ wa’-Milal wa’l-Nihal, 4/139. 
And Allah knows best.