1/8th 4S typical speed and run times?

[pete2222]

Can anyone advise what sort of speed I might expect if I converted one of my nitro buggies to brushless. I really want to know would a typical 4S set up be noticeably faster than my B4, which has a 6.5T motor. Would it be as fast as one of my 1/8th nitros. (I have an RB S5 engine and also a HB.26) . I just want to know what I'm going to expect for the £ it would cost me. I just drive in parks, not racing.

And secondly, what run time might I expect from a 4S 5000 mAh battery. Thanks for your answers.