why is there 4 bolts when it only uses three?

 

from what I remember when I changed mine, 3 bolt to the turbo exhaust flange, the other bolts to a bracket that is bolted to the engine, presumably to hold the turbo securely in position.

 

Mine has five, two to fasten it to the engine, via a bracket.

HTH

dunx

 

ARR, that may explain it, as when looking at up pipe it looks like only three are used. I have had the up pipe ported and looks like something has been cut off.
But because i've never changed the up pipe not sure what to expect.

 

yea mate mine has 5. did u get gasket with it or see outline where turbo fits to uppipe. if yea there the bolts to turbo an 2 to brackets