I know the SC61 is a dynamic power maker, but just wondering, how is it with internal wastegates? Any known problems with these, like spikes or creeps? and how big are these wastegates. Ive found some sites say they are 38mm internal wastegates? opinions are much appreciated.
I don’t like internal wastegates. IMHO you’ll have problems with the internal wastegate after 20psi.
We have done a couple 4g63 cars with internally gated 50’s and 61’s. They hold well in the low twenties, but after that can be questionable. Id recommend using a nice ebc such as the turbosmart e-boost2.
Josh
It’s sick how much boost those guys run on internally gated turbos! I’ve got a friend who runs 28 psi on a 20G! :shock:
i wish honda sleeves could handle that kind of pressure, instead we get to rip it apart and get it all sleeved up to handle crazy psi
bah…when someone out there keeps tuning 650 whp cars on stock sleeves…that starts to put that rumor to rest.
Now correct me if I am wrong, but logically, if internal wastegate on the sc61 works good at 20psi, shouldnt it work just as well or even better at higher boost levels. What I mean by this is that, MORE exhaust gases will be required to spin the turbine to achieve higher boost levels therefore LESS exhaust gases would be exiting the wastegate. do u guys understand what I mean.
I can see where you’re coming from, but I would imagine that the sheer volume of gas present at higher boost pressures might become too much for the relatively small diameter of the internal gate. To combat this, DSM owners will port out the opening for their internal gate as big as the flapper size will allow. They will even machine the casting a bit to allow the flapper to open a bit further than its stock mechanical limit.
What do u mean?
If the internal gate can handle the volume of gas at low boost, then shouldnt it be fine at high boost, because at low boost the volume of gas exiting the wastegate will be higher than at high boost?
anybody else got experiences with internally gated SC61?
This is why when running a small turbo, run larger wastegate, large turbo, small wastegate. Same diea that you got with less gases through WG at high bosot on internal gated
There is only so much volume of gas that can pass through a small wastegate opening. If the maximum volume of gas able to escape through that opening at a given exhaust velocity is reached, the gas will be forced through the turbine blades instead of the wastegate. This condition is usually caused by higher boost and/or smaller wastegate openings (all other conditions being ideal) and is known as a boost spike.