Garrett actuator

[Box stock T.]

Question regarding upgrading the standard wastegate actuator. I will be doing a set of id 1000cc injectors very soon and retune for my ba mk2  xr6t and was looking at changing it to a Garrett 8 PSI actuator. The car has a flash tune done lower typhoon intake crow valve springs and its running between 10 and 12 psi. MTQ here in adelaide have them. Im hoping to be able to  unbolt the 3 psi stock actuator and set the stonger one to the same length. Any info or input will be helpful. 

[Box stock T.]

Adding to this thread. I also have the option to go to a 11.8 psi actuator for the same coin. I would be thinking it will be retuned to around 14 psi after new injectors and 255 intank fuel pump.

[Puffwagon]

Because the new actuator won't open until 7 or 8 psi the car will run through possibley untuned parts of the map.

Under part throttle it will probably be lean with the new wg actuator. It will make more boost for less throttle opening as it revs, rather than ditch it early with a smaller wg spring. 

If you can't tune it yourself then at least get it checked on the dyno at full and also part throttle. 

The wastegate may come with fitting instructions. Follow them regarding preload.

Depending on how the boost was tuned you may end up with an extra 5 psi or so. 

Fit it and drive off boost to your tuner for checking.  

[Puffwagon]

Also get the bigger actuator if you are going to be running more boost than the gate spring is rated for. 

[Box stock T.]

Okay cool. So the 11.8 psi is a better idea. General rule of thumb is if you are running 14-15 psi of boost it will drop off to around 12-11 psi. Also is the flapper valve mod with the 11.8 actuator a good option with the injectors and fuel pump upgrade plus retune on a ba mk2. The mod allows for more power on less boost which inturn take pressure of the ba's weaker rods. Cheer Mr Puff...

[Puffwagon]

I think you should lose more like 1 or 2 psi through a cooler. If you are losing nearly 25% then you should look at upgrading.

I didn't do the flapper in my car and have good boost control. I have 15 psi when available to 17 after 4500rpm, on a 12 psi wg. I have run 13 before. If it is not overboosting then a bigger wg isn't needed. The gas is getting out.

Boost won't hurt your rods, tuning will. Pressure over time is something to consider that will save rods from destruction. This is why some tuners will bring the boost on slower.

 Adding an extra 20 psi of boost to a combustion chamber is nothing compared to combustion pressures in excess of 1000 psi. 

I would look at replacing your stock cat at the same time as your other mods. This will reduce heat in the head and back pressure, allowing for more timing and more power with less boost eventually.

If you're getting it tuned once then you should do what you can beforehand, except injectors obviously.

There are a few blokes that know this stuff inside out on this forum and they have tuned these cars a lot more than I have. Perhaps they can lend some more specialized advice to you.

 

[Box stock T.]

Cheers again Puff im dicing up between the high flow cat and fuel pump mod this time round. $$$ wise.

Its either injectors, high flow venom bolt on and actuator 

or injectors,  fuel pump ( 255 walbro ) and actuator. with a retune on both opitions of course. 

Thanks for the reply Mr Puff.

[Puffwagon]

Just do all of it if you can. The pump is only $100 or so. You will need it I think.

The cat and dump from venom did the trick for me to get it working better.

[JETURBO]

You want the 8psi Garrett actuator not the 11.8 where yours will need to be at 

you typically only need the port and flapper job after a high flowing cat/exhaust is fitted 

boost is the killer on BA's hence why most tuners will cring at someone asking for 18psi on their BA vs 14psi with a strong timing scale 

Martin knows these cars very well just do what he's recommended and leave it at that for one of a few reasons ...

he will charge you twice as much to "re fit" an actuator you installed vs letting him supply and fit one

Martin will also only fit parts he knows he can generate results with ... Not what you "think" parts will work 

if you feel you want to do all the work yourself ask to talk to Paul at MTQ, if he doesn't know the answer he will just ring me anyway and ask like normal  

[Puffwagon]

There ya go. This bloke has been tuning these cars for a few years now and knows what's needed.

Listen to him. 

Fwiw my stock pump ran out at 12psi and 4500rpm but it was quite gross when I pulled it out.