bobxyz
Board Member
- Joined
- Aug 29, 2014
- Location
- Boulder CO
Now I vaguely want to hook a PSI gauge to my exhaust manifold and see how high the PSI gets when it's making 20 psi of boost.
Not enough to actually DO anything about it, mind you.
I haven't done this yet either, but it's on the list of things to add to racecar V....whatever version it is.
I'd really like to see some different plots showing intake/cylinder/exhaust pressure versus rotation for a turbo engine and a few different operating points (idle, cruise, max boost).
Somewhere (maybe Heywood?) I remember seeing a plot that showed the expected blowdown pressure peak, followed by flat-ish presure for the rest of the exhaust stroke, but then a jump in pressure (to intake boosted level) at overlap. No reversion at all. If anyone knows where to find some example plots, that would be great.
Not to digress too far, but how do I account for an intercooler when using a compressor map to size a turbo? I know there will be some pressure drop across the intercooler, so the PR needs to be bumped up over what's desired on the boost gauge. For flow, the intercooler is going to drop temperature and condense the air so that the compressor needs to supply extra CFM to the intercooler to keep up with the engine CFM. Is there a standard way to scale compressor CFM for the estimated cooling?