Just want to know that if i create a SP list with more then 64 Single line of texts, which is possibly the limit before row wrapping happens how does the performance get affected. Is it totally not possible to create more than the specified column limits? My references are - Sharepoint list column limit http://www.sharepointsecurity.com/sharepoint/sharepoint-development/understanding-rows-in-sharepoint-2010/
You can still go beyond the 64 single-line text column as supported limit in one list is 256 columns.
But the issue is, when a new row wrapped it put the load on the SQL server which causes the performance issue. Now it depends on your hardware specification and also how many more columns you need.
Performance decrease require the testing at your end, you may get the slow sites loading, unexpected error during that time frame, SQL data locks, high resource utilization on the server.
From my experience that the wider a list gets, the worse it performs. Certain browsers, like Internet Explorer, choke when rendering large complex views of data, often taking minutes to display or simply locking the system entirely. Lastly, there is a real-world limitation on how much data a human being can digest on a screen which is practically speaking, around 50 columns. Data Entry in such a system sounds like something bordering on the sadistic.
I would recommend you to NOT save your data in sharepoint , when talking about this amount of data. Save your Data on a SQL-Server (this could be the same sql server as your content-databases). But save it in a structure, that you designed. You can than access the data through a webpart or external lists. SharePoint internally saves all ListItems in one table - this is an advantage for the search engine, but as that table has a limited amount of columns it also has its drawbacks.
You might want to re-architecting this solution.Split up the columns by two lists.