Well it turns out my GB270 has a hole in the exhaust manifold. So what do people recommend as a replacement? Also is it worth having it heat wrapped?

Scoobyworld have the afterburner manifold on offer at the moment for £315, so that's tempting. Either that or something with the Harvey up pipe.

Cheers

 

depends on power standard ported headers work best up to 400 then after gt spec ones are best suited

 

Silly question but what's the difference (although I'm unlikely to go over 400bhp)?

 

im sure its all to do with the flow but i ran my standard headers to 400hp no worries, then went for gt spec but i tried to retain standard ones as mapper said you get better results with standard ones. if your just after the standard headers ive a set for sale but if want aftermarket ones avoid any with flexi joints

 

If you go to tubular headers too early (ie. turbo too small to push enough air through the larger volume quick enough) your set up gets more lag. I took my standard headers off to fit my ported ones so I have a set of standards spare in good condition going cheap. Pm me if interested.

Adam

 

Would I need a remap with the Harvey up pipe/headers? Iirc the hawk doesn't have the cat in the up pipe, so presumably the difference in exhaust flow isn't as great?

 

my standard up-pipe flowed well and spooled well on standard headers to 400hp, i then changed to GT spec 3 bolts with harvey smith up pipe and lost bit of spool as it pulled the torque a bit further up the rev range horses for courses