Looking to start my Divided Turbo Manifold, and I need to get some Wastegates. I was planning on getting 2 38mm Tial MVS gates, now I'm second guessing myself on if I should go with 2 44mm MVR's. I won't be using the coolant feature on the MVR's if I go that route, but just the larger size I feel I can control the boost better on the 44mm vs. 38mm. Any feedback on either option from experience would be great to help make the decision. Turbo is a S480 Boostlab. Bridged motor at 15-25 lb

 

Manifold design, waste gate location, turbine and housing size, as well as target boost levels are what is needed to be considered for waste gate sizing. If you're wanting to run an s480 at only 15psi, first of all why are you doing that, second of all, you'll probably need a 60mm gate on the housing in order to maintain those boost levels.

Why are you building a bridge ported engine with an s480 and running 15 psi?

-J

 

Hmm, well it's a Divided manifold design with twin wastegates. 1.10 housing, and I would like to be able to control boost from 15-25 psi. The only reason why I would like to be able to control boost at 15 psi is for launch, stage it up to 25 from there, and the reason why I'm building a S480 Bridge motor is the same reason that I'm posting questions on this section of the forum "Drag Racing."

 

I went with turbosmart 40's

 

spot on

As for the dual wastegates i personal believe that it complicates things for no reason

The s480 at 15 psi will probably make no power.. i had the same thing with my gtx4294r.. these turbos dont flow at low boost..

 

Tial 38's, done and done whatever it makes at launch I will just have to deal with and adapt around it. Thanks for the advice.

 

Same here

 

I have 2 Tial 38's and they work fine at any boost level on the GTX4294R.

I started with 7psi springs and grew into 15psi springs as I tuned for more power. I typically see 28-30psi now with the boost controller set at 50% duty cycle. I doubt you really need anything bigger.

 

Good to hear, just wanted reassurance from experience. Thank you!