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

A HPA vid a day keeps the blown engine away.

Yaaaay, just what I needed on my day off! HP Academy coming through, as usual.

@hpa101

10 ай бұрын

Enjoy your day off mate! What have you got planned?

Interesting episode ! I gained nearly 100 hp when changing manifolds and Turbos, on the same boost pressure. The new compressors probably works at higher efficiency, but the largest portion of the gain was undoubtedly the lower back pressure. And I had to pay with slightly reduced transient response sub 3500 rpm. And the threshold where boost build up is possible were moved up about 350 rpm. Change was from Garrett GT1752s to Mitsubishi TD04 18T, on my BMW 635 csi. (3,5 liter I6)

"I don't wanna just sit here and talk for 45 minuties", video duration: 42:58, Yre goood!!! very good!

Link easily handles EMAP. In fact, using a couple Math Blocks - you could set any axis you want to MAP/EMAP*wheelspeed^2 + Pi * Log(fuel pressure).....not that you'd want to....

As usual a great video Having spent a number of yrs at Pikes Peak We always had trouble with our twin turbo 430 cubic inch methanol powered car maintaining hp when over 11,000 ft We scarified power at the bottom of the hill to keep our exh back pressure in check towards the top Thinking you can adjust on the fly is madness You’ll have it off the side in no time Load curve is the only way But damn it takes time to map

@hpa101

2 ай бұрын

There's always some sort of trade off eh. If you're into podcasts we've had a few guests who have been tuning for Pikes Peak. Might not be any new insight in there that you haven't already experienced but possibly some enjoyment from hearing others share the familiar struggles: www.hpacademy.com/search/results/?q=pikes%20peak - Taz.

Might have missed, as this is running in the background, but...but Depending on the application, it may also be useful to measure the post-turbine pressure, too, so the actual drop across it cn be known, and whether the rest of the exhaust system, if used, is also a factor that needs to be addressed? The material used for the pressure transducer stand-off is also important, one with a low thermal transfer should be used, eg. a SS, rather than a copper based tube, and thermal sleeving/shielding would be a good idea close to the manifold, to reduce radiant heat absorption. Not something I've tried, but perhaps a heat-sensitive paint, such as used for brake temperature checking, may be an option for monitoring the temperature of the transducer or, at least, estimate if from the temperature gradient from the manifold to the transducer? For those interested in forced induction, I would strongly recommend Mr Gale Banks' videos, they're primarily on diesel engines, but all the basic points are directly transferrable to spark ignition engines. www.youtube.com/@bankspower

That's an extra clean set of overalls on Andre...

turbine drive pressure is very important to keep an eye on.

Hypothetically can you use something like an electronically controlled straight gate running off a table to modulate EMAP while still keeping enough pressure to run the turbine and maintain a boost or torque target? Can this widen the effective range of a turbo or make it feel smoother or more N/A like for circuit style driving or in my case riding? This is what I'm planning on my bike along with a 32mm DBW Bosch anti surge. My thinking was that at high rpm and IMAP I didn't think all that back pressure was required to drive the compressor but rather was a limitation with the wastegates especially poppet style and the control limitations of using springs etc

Did u guys get that laptop because it says hp

@hpa101

10 ай бұрын

No, but we should have 😂 - Taz.

@Zackrevoluzion

10 ай бұрын

LMAO exactly what i thought when i saw HP on the laptop

Awesome ❤

Can we make a petition to stop calling referring to it as exhaust back pressure and call it turbine drive pressure (turbo) or exhaust restriction pressure (NA or post exhaust housing). It makes no sense to me because we dont refer to positive intake manifold pressures as intake back pressure.

@patx35

9 ай бұрын

In a way, it's better to call positive manifold pressures as intake back pressure, as that's what's actually happening in the engine. There's a common misconception that boost pressure equates to CFM, which quickly gets annoying when people compares two completely different engines by their target boost pressures, or equates boost pressures directly to power output.

@snotrocketfiesta

9 ай бұрын

No, the industry standard term is TIP. EMAP, and others, are internet terms.

Would you say that one would prefer to have absolutely no mechanical filtering on the emap signal considering you could potentially (I'm guessing) use the than visible exhaust pulses to identify missfires and maybe even inequality between cylinders combustion efficiency? How hard would it be to cross reference the "noisy" emap signal with a crank+cam signal to overlay and identify which exhaust pulse corresponds with which cylinder?

Very good info, i need to try it but dont have any extra outputs left on elite 1500

@GroovesAndLands

10 ай бұрын

You need an input, not an output. You can get CAN based I/O expanders.

Is there a relationship between manifold temperature and manifold backpressure ?

@jesse9638

10 ай бұрын

Absolutely. Guy Lussac’s law and then the ideal gas law. Basically, if volume is constant, relationship between pressure and heat are directly proportional. I’d dig in a bit more to Boyles Law, Charles Law, Guy Lussac, and Ideal gas law for more theoretical knowledge if you’re interested. Cheers.

Diesel guys have been calling it drive pressure for years. How much energy it takes to drive the turbine wheel.

@gordowg1wg145

10 ай бұрын

Very much on point - while using exhaust energy to drive the turbine "seems" like free energy to the ignorant, there is a definite cost to, at least partially, drive the turbine against the impellor loading.

Adaptronic does not exist anymore ?

@350gtboi

10 ай бұрын

After it got bought out by Haltech, they took Andy’s IP and used in the Haltech and then Haltech was sold to a USA company and I guess they decided Adaptronic was redundant.

Team, Regarding the installation of sensor, what effect does temperature removal have on the EMAP. Presumably based on combined gas law, a decrease in temperature correlated with a decrease in pressure, ie, as measured vs MAP, there will be an error? Whilst in kpa as a unit, 5 percent or there abouts may not be a large error, it’s still a factor. Also, Regarding tuning, can you infill some information as to tuning against EMAP with respect to when the turbine housing/wheel becomes saturated….ie based on load, you can delay peak load later to keep map/EMAP in check to reach ‘power goals at high rpm’ (trade off being dogshit drive down low)? Great episode as always! Ta

@patx35

9 ай бұрын

One thing you completely forgot is that there's practically zero gas flow to the EMAP sensor. It's not that the coiled line would cool the exhaust gas, rather than it simply acts as a buffer between the sensor and the hot flowing exhaust. The gas in the line still would act as a spring, so yes, there's an increase in error, but it's not as significant as you think.

Just got my car back up and running again. My question is are the calculations just as simple as EMAP/ Map (boost pressure) or is it EMAP/(MAP+14.7)?

@gordowg1wg145

10 ай бұрын

Good practice would be to use absolute for both. MAP and "boost" are two different things, measured differently.

@spooler7828

10 ай бұрын

@@gordowg1wg145 That's how I did it and it make the most sense on the levels and power I recorded.

@spooler7828

10 ай бұрын

@@gordowg1wg145 I measured 42psi emap and 23psi boost pressure. 1.11 Drive pressure ratio. Right on the money. I go some more I can go. Twin turbo V6 so have two EMAP sensors.

I am looking for a turbo for my 4g64 mitsi with a small port rvr turbo head. Im running it in my l200 and I am after a turbo that will deliver enough mass flow to make 250 hp at 3000 rpm so nothing crazy, i use this wagon to tow my race car. I want as fuel efficient setup as possible in the 2000 to 3000 rpm range. My goal is to have the map at least the same, or higher than the emap. I am not hugly concerned about turbo lag. Does emap have any influence on the brake specific fuel consumption? Is this even possible to achieve on small engine like this? I would imagine a setup like this would drive similar to a commercial truck where it takes a second or so to build boost.

What’s inside those exhaust pressure sensor dampers? Curious how they work

@4familyman

10 ай бұрын

Most of the ones I’ve seen are just steel wool