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Dual Tial wastegates and spring choice with MAC

Hey guys,

So I recently switched to a 6 boost high mount running dual tial MVS 38mm wastegates. This will be my first time running this type of setup, target boost pressure will be 30, but possibly 35 psi. Both will be controlled by a MAC valve going back to a Wolf v550. Engine is a built 26/30 with borg warner 9180 turbo.

I have setup the springs in both gates for 23psi, with the idea that the mac valve can do the rest to 30. Can someone tell me if that's going to be OK?

Some people have told me that running 23 might be an issue when time to tune, is this correct?

Cheers. 

You are assuming that your set-up will run OK at 23 psi. If you are confident about that - no problem - but if there is any doubt you should have a set of lower springs to hand so that you don't have to return to the tuner for another session. Also if you find that you will be regularly running 35 psi you may want springs for 28 or so psi.

  • 3 months later...

As mentioned above, double check how many port MAC valve you have and if it's not a 4 port, buy one. MUCH better control and you can run softer springs with a much larger range.

FWIW, I'm running 0.9 bar springs and have no issue at 26 psi (bringing it back to 23 up top on purpose) using 4 port valves.

also I'd recommend finding a 12 watt solenoid version of the 4 port mac valve (made by circuit seven on ebay). they control duty cycle range is much greater (40% greater effective duty range) giving you better control resolution as the 4 ports are sensitive.

also a lighter spring in the gate will allow the valve to respond faster. as long as your diaphram to valve area is decent (>1.5), a 4 port will hold it closed with a very light spring.

effective duty @ 30hz for the 4 ports:

5.4watt is 22-62%

12watt  is 14-70%

 

 

alve

freq

approx Duty range %

3port MAC-5.4 watt

10

7-90

 

15

10-89

 

20

15-86

 

25

17-80

 

31

20-80

 

40

26-68

3 port MAC-C7-HI-FREQ

31

15-85

 

40

17-82

4 port 5.4 watt

10

9-87

 

20

16-70

 

30

22-62

 

40

25-40

4 port C7-HI-FREQ

10

6-90

 

20

10-80

 

30

14-70

Edited by burn4005
  • 3 months later...

i have the same setup

i followed tial’s spring chart for 23psi

for some reason we had boost reach 37 psi

i used two springs not the recommended 3 springs and boost stayed around 20psi

i would start with two and a 4 port mac valve that way you can go 20-40psi

i have the same setup

i followed tial’s spring chart for 23psi

for some reason we had boost reach 37 psi

i used two springs not the recommended 3 springs and boost stayed around 20psi

i would start with two and a 4 port mac valve that way you can go 20-40psi





my mistake

i’ve plumbed it wrong

follow Tials instructions PROPERLY and they’ll work fine

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