This is a classic 4 stroke car guy comment , I've lost track of how many conversations I've had with car guys regarding turbo stuff that dosent pertain to 2 stroke snowmobiles. Here's why.
1. Your 4 stroke is running valves , our 2 stroke is not.
OK?
2. Your 4 stroke has way more exhaust energy than our 800cc two stroke snowmobiles.
OK?
3. On an internal wastegate you have ineffecienys right before the wheel and right after, hurting flow , Depending on setup this is avoided with the external.
Where are these inefficiencys? If you look at their exteraal kit the exhaust must make a hard 90* corner to get to the wastegate this will create creep with enough pressure.
4. Take a look down the volute of a tial and a standard internal garret , easy to see the volute of the tial accelerates the energy into the turbine.
No wastegate accelerates the exhaust gas into the turbine they are designed to do the opposite...
5. Talk to the guys who have done the tests the tial flows more than a standard internal.
I know they flow mor . The only reason to flow more is if your internal set up can not move enough exhaust away from the turbine to keep the boost under contro . The internal should be plenty for most folks. You said yourself the sleds have less exhaust volume and pressure. And that said the lower the boost the harder to it is to control. The higher the boost the less exhaust you need to move away from the turbine.
Car guys have high ground speed , so an air to air makes sense. That's why they don't run water to air. Sled guys have snow everywhere so you can exchange your fluid with below zero snow , it's a no brainer.
Good for silber for offering this , step in the right direction , I look forward to seeing it at the snow show.
