Timing / tuning Tubo 8

[84uk900t8]

My APC system recently failed, so I had a bleed valve fitted as a cheap replacement. However I have stacks of power low down (up to 4000rpm) but it drops off above this (boost pressure only slightly drops), so to get performance I am constantly changing gear! I am told that adjusting the timing will shift the powerband up, but I am unsure whether to advance or retard, and by how much, or whether this will have any other effects. Or any other suggestions...

[john-w]

I have advanced my timing to 24deg instead of the stock 20, but i have water injection to overcome the increased tempertures you will get by timing advance!
The other thing with an 8v is the turbo is 40mm trim, where the 16v has 45, so you lose some power there, so you could change to a bigger garrett or go for a mitsubishi which will spool up from a lower rpm and give you improved acceleration, but you lose a little at the top end!!
Another tip for the 8v get some BP7EVX plugs their £6 each but you will notice the difference in starting and performance!!