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Just got my high flow back and installed on my rb25. Problem is when boost reaches its preset max it pulsates up and down at a fast rate 1-2psi. It Is fine untill it reaches full boost. I've been told it isn't surge because it only happens after full boost...is this correct. Stronger waste gate actuator needed????

pls help.

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I know of one guy who had his highflowed and did the exact same thing, had to take it back because they hadnt matched the wheels properly or something. ask the guys who highflowed? they would have a good idea of whether its the conpressor/exaust wheels or your wastgate actuator.

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I think you are refering to surge. I have had a turbo that surged before and I can say this is different. I tired a piece of wire to the waste gate and put it through the firewall. I applied preasure to the actuator when reaching full boost and it fixes the problem. I will move the waste gate actuator further back to increase the tension slightly and see how it goes. I have heard of problems with surging when using the RB25 exhuast housing. I am using a VG30 which has a bigger A/R.......fingers crossed.

specs: Comp T04B Vtrim

Turbine and housing are VG30

this setup has made 245rwkw@12psi on a 3ltr.

ps makes full boost before 3000rpm in third.

pps Who is the best dyno tuner in Adelaide???

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Im getting towards that now, but, I like to have a go myself and it doesn't cost any money. I have experimented with altering then tension on the wastegate and managed to move the surge around the rev range but no aleaviate it all together. I'm still trying different things so I'll keep ya posted... might be one of u one day =)

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