Exhaust Back Pressure Vs Turbocharging For Car Nerds

🤷‍♀️ Building a fast car? Get $400 OFF the all inclusive VIP online course package deal: https://hpcdmy.co/vipy75
✅ Kickstart your EFI Tuning knowledge. Get 50% OFF your first online course: https://hpcdmy.co/offery75

The back pressure in the exhaust system is something that’s usually completely ignored, however, it can be a useful input when it comes to analysing turbo sizing and turbo performance. In this webinar, we’ll cover how you can log turbine inlet pressure (TIP) or exhaust manifold pressure (EMAP) data and how it can be incorporated into your tune.

TIME STAMPS:
0:00 - Introduction
1:16 - Back pressure and forced induction
2:03 - What does the TIP/EMAP data tell us?
4:16 - Data overview
7:36 - EMAP to IMAP ratio
11:53 - Drag racing example
12:36 - Technology is moving the ratio goalposts
13:47 - How do we get this data into our ECU?
21:35 - Using data as a load input
31:39 - Questions
------------------------------------
🏆 Win an ECU, engine components, wiring tools, alignment setups or more. Free entry! Here's the latest giveaway, enter now: https://hpcdmy.co/giveaway

🏎 Want to learn how to EFI an aftermarket ECU like a MoTeC, Haltech, Link, AEM, Syvecs, EMtrom, Maxx, Ecumaster, MegaSquirt, Arduino, MicroSquirt, Holley, FuelTech, ME or something else completely different? Fee lessons right here, enroll now: https://hpcdmy.co/EFI101y
------------------------------------
LINKS:
Website and Courses: https://hpcdmy.co/hpa
Podcast: https://hpcdmy.co/podcast
Merch (HPA tees & hoodies): https://hpcdmy.co/merchy
------------------------------------
TRANSCRIPT BEGINNING
It's Andre from High Performance Academy, welcome along to another one of our webinars.
Now today we're going to be talking about a topic which a lot of people completely overlook or don't even give any consideration to and this is our exhaust manifold back pressure.
There's a few ways of shortening that down, eMAP is one of the common ways you'll see that expressed, exhaust manifold absolute pressure.
Turbine inlet pressure or TIP is another way but basically what we're looking at or talking about here is the back pressure that is between the exhaust ports on the cylinder head and the inlet to the turbine housing or turbine wheel on the turbocharger.
So while yes we will have some level of exhaust manifold back pressure on a naturally aspirated engine, generally when we are referring to eMAP or turbine inlet pressure, it is as a result of some analysis that we want to do for a high end turbocharged engine.
So today we're going to talk about why we want to do this, what advantages this gives us and then we're going to talk about some of the intricacies involved in actually getting that data into your ECU or data logger and then how we can interpret or even use it as a load axis or a load input for our ECUs.
So this doesn't necessarily mean that you can't use everything that we're going to be talking about here on a naturally aspirated engine but obviously the sort of back pressure level that we're going to see on a naturally aspirated engine is much much lower so less significant and there's a little bit less to learn.
Particularly it's probably not going to help you on your naturally aspirated engine to learn too much about your turbo sizing which is where it comes in, particularly with our high end turbocharged engines.
As usual, we will have a chance for you to ask any questions so if there's anything that I talk about today that you'd like me to explain in a bit more detail or just anything generally related to this specific topic, please ask those questions in the chat and we'll jump into those at the end of the lesson.
Alright so the first thing is what are we going to be using this data for, what's it actually telling us? Well particularly when it comes to sizing a turbocharger, what we're trying to do is size the turbocharger so that first of all, we have the ability to flow enough inlet air into the engine to support the sort of power levels that we're wanting to get.
Now if you've looked at any compressor maps, they're relatively straightforward, we've got some other webinars which you can look at on turbo performance that will dive in a little bit deeper and explain what the axes in the islands on those compressor maps are so choosing a compressor that's suitable for your particular engine in terms of the capacity of your engine as well as your power aims is not particularly difficult these days and there's some nice tools from the likes of Borgwarner with their Matchbot that will go a long way to helping you with that.
General rule of thumb there is that you're going to need around about 10 pounds of airflow per minute, give or take, for around about 100 horsepower.
------------------------------------
TAGS:
#highperformanceacademy #buildtunedrive #emap #tip #backpressure #exhaust #learndriveoptimise #motorsport #learntotune