WhiteBlue wrote:3. No fluids bypassing the exhaust turbine can be fed back into the exhaust system. I guess that kills waste gates as you cannot exhaust them legally by any other means as the designated exhaust system.
I'd really question some of your interpretations of the regs (in the link you provided) based on the wording of 5.8.1, 5.8.2, 5.9.1 & 5.10.2 which make clear distinctions between "
fluids" and "
exhaust gases" and also allow the use of "
devices needed for the control of pressure charging systems" and further describe the legal exhaust systems under the collective regulations within 5.8 .
5.8.1 With the exception of incidental leakage through joints (either into or out of the system), all (and only) the fluids entering the compressor inlet must exit from the engine exhaust system.
The wording to me indicates that they are looking at ways to stop the use of water or fuel for charge cooling while allowing for the situation where "fluids" may enter the intake during say wet races or thought other non-conventional mechanisms (pick a corner case scenario).
Water and/or oil may "leak" past the CHRA bearings & seals of the valve stem seals etc and and incidental leakage through "joints" is OK for unburnt fuel/oil that may seep past the exhaust slip joints .
However, my read is basically this is setting down that only "fluids" that come into the system pre-compressor through the compressor inlet orifice are acceptable allowing for rains etc. This wording precludes the use of post compressor fluid inclusion and post exhaust valve fuel inclusion as
ALL fluids must pass through the compressor inlet orifice, the compressor and the engine and exit via the exhaust, which leads to 5.10.2.
5.10.2 There may only be one direct injector per cylinder and no injectors are permitted upstream of the intake valves or downstream of the exhaust valves.
This prohibits using an "injector" upstream of the intake valves and downstream of the exhaust valve, but it doesn't stop using another system to introduce fuel or another liquid either upstream or downstream of the intake/exhaust valve. A constant feed or one that isn't regulated through a pulsating solenoid or "injector" would still be allowable without 5.8.1 if you could show that the system did not make use of the what falls under the technical definition of an "injector".
5.8.2 Engine exhaust systems may incorporate no more than two exits, both of which must be rearward facing tailpipes, through which all exhaust gases must pass.
This definitively separates "exhaust gases" from "fluids" and leads to my interpretation of 5.8.1 and 5.10.2 above. A gas is not a fluid under the regulations. It allows two exits which may be one for the turbine gases and one for the wastegate gases. You could merge them and split them again for balance were you looking for a balanced aero effect etc. But there is nothing under "
5.8: Exhaust Systems" that precludes merging the wastegate and turbine gases then separating them again into two (2) exits.
5.9.1 With the exception of devices needed for control of pressure charging systems, variable geometry exhaust systems are not permitted. No form of variable geometry turbine (VGT) or variable nozzle turbine (VNT) or any device to adjust the gas throat section at the inlet to the turbine wheel is permitted.
So you can have a wastegate(s) as variable device(s) "needed for control of pressure charging systems". Wastegates are definitely permissible under 5.9.1
WhiteBlue wrote:6. Use of refrigerants (latent heat) other than fuel in cooling systems including charge air coolers (inter coolers) is forbidden.
So you “can” use an intercooler, just not an air-to-liquid charge cooler. An air-to-air charge cooler would seem legal under the regulations though.
