It's a hole/ring in a plate sandwiched between the flange of the dump pipe/cat to restrict exhaust flow and control/limit boost levels.

Not the ones we have removed, it is a restriction ring welded inside the exhaust pipe

Try this. Wish I'd done a before and after dyno run to compare.

My link

Edited 08/04/11 11:18 AM08/04/11 11:18 AM by Barra

I pulled 353.7rwhp at summernats 24 which is about 263.8kw completly dead stock auto XR6T with about 45000k's onit,

Edited 13/04/11 11:14 PM13/04/11 11:14 PM by AY35XC

Run in 3rd, figure is not comparable to those whose ran in 4th.

Edited 16/04/11 04:05 PM16/04/11 04:05 PM by winstor

I was a bit down about mine at first. It was only making 225rwkw stock (auto) but the motor had only 3,500k on it. Flash only and she came up to 262rwkw. Retuned at 7,500k with cooler upgrade etc and now makes 315rwkw. This was all on the same dyno - same tuner.

Good numbers Bomber. I'm due for another tune very very soon- Very similar mods to you actually minus the venom cat (for now) + Stainless 4" airbox. So I'd be quite happy those numbers..... for now.

Does your boost ramp on hard or progressive? Thinking about 2 tunes, one coming on hard say up to 15 then taper to 13 (just for fun times) and one just 13psi as it sits now. I'm making 272 rwkw without the F6 injectors in yet and a new tune to suit air box. :mail:

yeah mine comes on nicely Barra but not hard. The problem we all have is the standard actuator falls off towards max rpm. You won't be able to hold 15psi for very long mate. To remove it, you need to take the turbo off. Do that, and you may as well do the turbo mod at the same time. Then you ask yourself, do I want to bother spending money on the small turbo?

I like the little turbo and the low down grunt it gives. Time over, even though I'd potentialIy only gain maybe another 10-15rwkw, I'd remove the turbo, mod it, ceramic coat the housing and manifold and upgrade the actuator. That would enable my tuner to hold say 14psi with no lumps in the mid range or fall off at the end.

Tempting I know. Mine is more of a hwy car anyway so I like the low down boost too. In the mid to top range you are already going too fast on the street.

Edited 12/11/11 07:23 AM12/11/11 07:23 AM by Barra

For example

Edited 12/11/11 07:27 AM12/11/11 07:27 AM by Barra

my FG F6 made 386rwhp stock with a XR8 airbox & K&N..