I have been in search of a T4 twin scroll GT35r turbine housing and noticed that ATP is the only manufacturer. I have also noticed that there have been numerous complaints and also saw first hand how there housing are prone to cracking. I am in the midst of talking to a vendor who can make stainless steel turbine housings and wanted to know if there was an interest in this type of product due to me having to place a bulk order.

 

may i ask why you want to go t4?

 

because it spools faster than T3.

https://www.evolutionm.net/forums/ev...erence-12.html

https://www.evolutionm.net/forums/ev...5-r-lag-2.html

 

Can't you just do this
http://www.full-race.com/store/turbo...turbo-kit.html

 

As you can see, it comes with an ATP 1.06housing