Power delivery issues or is it just me?

[Eagle7]

I'm encouraged by some of the reports, here. I just visited a local dyno shop today where I'll take both cars for a baseline once the heatwave breaks. It sounds like air flow may be a big bottleneck and the Eventuri sounds intriguing. I may start with that and then see whether cat delete and ECU changes are needed.

@Eagle7 - I'd be super interested to see your dyno results. Even if the conditions are somewhat incomparable it'd still be interesting. I'll plan to share my results for the two cars as well.

I'll add - the dyno shop asked me to look into whether the car has a "dyno mode". That's probably been answered elsewhere but figured since I'm posting...

All the info is in my journal thread "Adding Lightness" https://www.emiraforum.com/threads/adding-lightness.4796/page-5 but here's the dyno chart with the baseline run and Eventuri run:

The dyno operator for mine said he just had to sit in it on the dyno and "drive" it were his exact words, (just let it run I'm guessing) and after a bit the car recognized it was on the dyno, and it turned off the traction controls. He had it in track mode. The dyno was engaged and running, but the car was just idling basically. I think he sat there with it running like that for about a minute if I recall correctly. Might be different for a different type of dyno, but that worked for mine.

My results were with the 3rd cat still in place. No ECU changes were needed.

 

[Eagle7]

Read in the other posts that the gauze could potentially help keep moisture out of the intake/MAP. That seems reasonable.

That was my guess. If you're driving in the rain, especially heavy rain, water is being sucked into the side intake. My guess is the gauze might help to keep the paper element of the filter from being saturated with water so it doesn't stall the engine.

 

[seriously]

I'm hoping there is a way for rain to escape the "intake area" should there be heavy rain? I have had a hydrolock situation in the past, but that was from a cold air intake being submerged in a deep puddle. Engine did not survive.

 

[Eagle7]

I'm hoping there is a way for rain to escape the "intake area" should there be heavy rain? I have had a hydrolock situation in the past, but that was from a cold air intake being submerged in a deep puddle. Engine did not survive.

There are exit holes on the bottom of the housing, at both corners just in front of the gauze. You can see the edge of the gauze through the holes, so this is something they've thought of and addressed.

 

[kitkat]

Read in the other posts that the gauze could potentially help keep moisture out of the intake/MAP. That seems reasonable.

Entirely possible, probably doesn't matter a ton especially those of us living in relatively dry climates.

 

[flyingcar16]

Quick update. I took my bone stock '21 Evora GT (~5k miles) for a dyno run (or 3)...

A few notes about these runs which were in the order listed: red, blue, green. The measurement was from the tire, not from the axle as in @Eagle7's case.

For the first run, the car was in race mode. For the second and third runs, ABS and traction control lights came on and I was unable to activate 'sport' and 'race' modes. I speculate that this was the closest these cars have to a dyno mode. Check engine came on at a couple points briefly in between runs but cleared quickly.

The second run was the cleanest and highest peaking at 378hp. The rev limiter seemed to cut in earlier than expected around 6500 (or maybe 6700) according to the tach. Doing a couple comparisons of the tach vs. the dyno's coil tap seemed within 50 RPM when I checked at a few different revs between runs.

The third run occurred after we cooled the intake with an external fan. We suspect that cooling this much may have led to the drop in the third run. In any case, the variability we see here (~10 peak hp) isn't great but seems explainable between the mode weirdnesses and the cooled engine.

I've ordered an Eventuri intake and plan to take the Emira for before and after dyno runs (I presume 3 each) where I can take what I've learned from the Evora runs and hopefully achieve a little more consistency. Also going to try and pick a day with a similar ambient temp so the numbers are somewhat comparable between the cars.

Will update soon.

 

[seriously]

Quick update. I took my bone stock '21 Evora GT (~5k miles) for a dyno run (or 3)...


View attachment 48793

A few notes about these runs which were in the order listed: red, blue, green. The measurement was from the tire, not from the axle as in @Eagle7's case.

For the first run, the car was in race mode. For the second and third runs, ABS and traction control lights came on and I was unable to activate 'sport' and 'race' modes. I speculate that this was the closest these cars have to a dyno mode. Check engine came on at a couple points briefly in between runs but cleared quickly.

The second run was the cleanest and highest peaking at 378hp. The rev limiter seemed to cut in earlier than expected around 6500 (or maybe 6700) according to the tach. Doing a couple comparisons of the tach vs. the dyno's coil tap seemed within 50 RPM when I checked at a few different revs between runs.

The third run occurred after we cooled the intake with an external fan. We suspect that cooling this much may have led to the drop in the third run. In any case, the variability we see here (~10 peak hp) isn't great but seems explainable between the mode weirdnesses and the cooled engine.

I've ordered an Eventuri intake and plan to take the Emira for before and after dyno runs (I presume 3 each) where I can take what I've learned from the Evora runs and hopefully achieve a little more consistency. Also going to try and pick a day with a similar ambient temp so the numbers are somewhat comparable between the cars.

Will update soon.

Those torque numbers look really strong relative to the HP.

 

[flyingcar16]

Those torque numbers look really strong relative to the HP.

I assume you mean peak torque to peak HP? (Otherwise hp is just proportional to torque*rpm). Peak power is maybe a little higher than I expected. Very keen to see how the two cars compare on the same dyno and expecting the Emira not to have as strong a baseline as the Evora if my seat/pants gauge is at all accurate.

 

[seriously]

No I mean for the EMIRA torque is listed at 317 and hp is 400. I expect it's slightly higher in the Evora GT is something like torque 317, hp 416 - likely a function of higher RPM limits.

your torque number is high 333, and your hp low 378. We all know dynos are more about relative differences between runs, not absolute measurements. But if your torque was higher than expected, I would have also expected your HP to be overstated. Maybe you didn't rev the engine to redline and thus didn't achieve true peak HP.

 

[flyingcar16]

No I mean for the EMIRA torque is listed at 317 and hp is 400. I expect it's slightly higher in the Evora GT is something like torque 317, hp 416 - likely a function of higher RPM limits.

your torque number is high 333, and your hp low 378. We all know dynos are more about relative differences between runs, not absolute measurements. But if your torque was higher than expected, I would have also expected your HP to be overstated. Maybe you didn't rev the engine to redline and thus didn't achieve true peak HP.

If the torque was very /very/ flat then we'd expect that peak (333) to be predictive of peak HP. But in this case peak HP is reflective of the torque (300-320 ft-lbs) delivered at higher RPM (~6250).

Entertainingly, I was the one running it through its paces and I can attest to having it floored until the rev limiter kicked in on each run. So maybe not to technically to redline, depending on whether you consider the rev limiter to be redline. That difference is a bit out of my control.

 

[Eagle7]

Your best of 378 hp to the rear wheels is pretty close to what I got with 369 on mine, and about right considering your Evora is rated at 416 vs the Emira's 400. That sits right within the drivetrain loss factor. It'll be interesting to see what you get with the Emira stock, and then with the Eventuri.

 

[Blackthought_]

Quick update. I took my bone stock '21 Evora GT (~5k miles) for a dyno run (or 3)...


View attachment 48793

A few notes about these runs which were in the order listed: red, blue, green. The measurement was from the tire, not from the axle as in @Eagle7's case.

For the first run, the car was in race mode. For the second and third runs, ABS and traction control lights came on and I was unable to activate 'sport' and 'race' modes. I speculate that this was the closest these cars have to a dyno mode. Check engine came on at a couple points briefly in between runs but cleared quickly.

The second run was the cleanest and highest peaking at 378hp. The rev limiter seemed to cut in earlier than expected around 6500 (or maybe 6700) according to the tach. Doing a couple comparisons of the tach vs. the dyno's coil tap seemed within 50 RPM when I checked at a few different revs between runs.

The third run occurred after we cooled the intake with an external fan. We suspect that cooling this much may have led to the drop in the third run. In any case, the variability we see here (~10 peak hp) isn't great but seems explainable between the mode weirdnesses and the cooled engine.

I've ordered an Eventuri intake and plan to take the Emira for before and after dyno runs (I presume 3 each) where I can take what I've learned from the Evora runs and hopefully achieve a little more consistency. Also going to try and pick a day with a similar ambient temp so the numbers are somewhat comparable between the cars.

Will update soon.

Interesting results. When I compare the results to Greg’s for the Emira (https://www.emiraforum.com/threads/grp-intake-shootout-dyno-testing.4979/) HP is for the Emira is much higher. Is that par for the course given dynos are not all the same? The torque being a bit higher for the Evora GT makes sense given the weight difference.

 

[Eagle7]

Interesting results. When I compare the results to Greg’s for the Emira (https://www.emiraforum.com/threads/grp-intake-shootout-dyno-testing.4979/) HP is for the Emira is much higher. Is that par for the course given dynos are not all the same? The torque being a bit higher for the Evora GT makes sense given the weight difference.

Yeah that's the thing with dynos, the different types each give their own results, which is why I like to stick with whatever one I start with. They're really only useful to show the differences from a baseline run, and whatever changes you make, as long as you're using the same dyno.

Weight doesn't make any difference on a dyno. The factors that can have an effect are typically the environment; altitude (air density), temperature, humidity, the condition of the dyno itself, etc. They're not perfect, but they are useful to give you some idea of what you've got for performance.

It'll be interesting to see what flyingcar gets on that dyno with his Emira.

 

[Tobiasz17azs]

That was my guess. If you're driving in the rain, especially heavy rain, water is being sucked into the side intake. My guess is the gauze might help to keep the paper element of the filter from being saturated with water so it doesn't stall the engine.

Would you explain this better to me Eagle. I had a feeling my engine stall once of two times after wash . It’s could be because of the filter ?

 

[Kimmax]

Would you explain this better to me Eagle. I had a feeling my engine stall once of two times after wash . It’s could be because of the filter ?

Check your lambda sensors. Mine were cooked after every wash

 

[Eagle7]

Would you explain this better to me Eagle. I had a feeling my engine stall once of two times after wash . It’s could be because of the filter ?

If enough water gets into the gauze, then that prevents air from flowing through, or interferes with it enough that it could cause a stall. My guess, and it's only a guess on my part, is the gauze was put there because it can shed water faster than the paper can, so if enough water, or snow, etc., makes its way into the intake, the gauze will prevent it from soaking the paper of the air filter.

This would be a good reason to NOT take an Emira through a car wash.

 

[flyingcar16]

Ok, mission finally complete. I took the Emira back for new runs before and after Eventuri install. I asked the operator to include the best run for the Evora GT, and the before and after runs for the Emira. Some very interesting results and some additional observations from the dyno shop.

Green = '21 Evora GT (peak torque 329.37, peak hp 367.98)
Blue = Emira run 1 (peak torque 309.07, peak hp 354.60) - stock intake
Red = Emira run 2 (peak torque 322.43, peak hp 367.69) - after Eventuri install

First, the intake seems to make a very noticeable difference, starting between 3000-3500. [side note: the uptick in the 3500-4000 range that seems delayed on the blue run is artificial. I had another "before" run that had that same shape, differing from the red run only in that the torque kicked up with the same delay as the blue, creating that little diamond-shaped gap. No idea what the cause of that delayed torque onset is but it doesn't seem to be related to the intake mod.] The power diff just from the Eventuri gets the Emira much closer to the Evora, with the torque only noticeably different over 4500 RPM.

Second, the Evora seemed to be limited to 6500. I was less confident about the Evora's system state (sport mode, dyno mode, etc.) than the Emira, which in contrast gave obvious indications that it "knew" it was on a dyno. The biggest tip off was a message that read "Test Mode activated. Parking Brake roller bench." The Emira went to what looks like ~6700 RPM, though torque was dropping fast enough at that point that peak HP wasn't helped much by the extra revs.

Third, stuff around 4500 RPM - that's where the Emira torque starts to drop off. The shop owner was watching the mixture, and believes the mixture is overly rich starting around that level and believes a leaner ECU map would "fix" the torque drop.

[EDIT]

Additional thoughts:

Test drive. I'm not sure I could say that the added power is super noticeable. I still feel a consistent, noticeable power bump at or just before 6000 RPM. I wonder if the map is slightly different when the Emira is in test mode because that bump is not at all apparent in either of the Emira traces. The power delivery still feels glitchy to me in the Emira - it seems a little debatable whether the traces bear that out. To my eye the Evora trace shows a noticeably smoother torque curve.

The Eventuri, if anything outperforms its advertising, at least in my case. Peak power difference looks to be over 20 HP, and is noticeable all across the RPM ranges that matter. The shop owner does a lot of tuning and was very surprised at how much difference an intake makes in this car.

[EDIT]

Intake noise is noticeably louder on the driver's side, especially with the window open.

 

[skydude]

Read in the other posts that the gauze could potentially help keep moisture out of the intake/MAP. That seems reasonable.

I get "Reduced Performance" after every car wash. I still have the gauze. Wonder what else could be getting wet. Once everything is dry the issue goes away.

 

[Eagle7]

I get "Reduced Performance" after every car wash. I still have the gauze. Wonder what else could be getting wet. Once everything is dry the issue goes away.

If the gauze gets soaked, it's going to reduce airflow until it dries out. If you're power-washing right into the intake, that would do it. Maybe stuff a towel in there while washing and rinsing the car to keep it from getting soaked.

 

[Eagle7]

Ok, mission finally complete. I took the Emira back for new runs before and after Eventuri install. I asked the operator to include the best run for the Evora GT, and the before and after runs for the Emira. Some very interesting results and some additional observations from the dyno shop.

Green = '21 Evora GT (peak torque 329.37, peak hp 367.98)
Blue = Emira run 1 (peak torque 309.07, peak hp 354.60) - stock intake
Red = Emira run 2 (peak torque 322.43, peak hp 367.69) - after Eventuri install

View attachment 50533
First, the intake seems to make a very noticeable difference, starting between 3000-3500. [side note: the uptick in the 3500-4000 range that seems delayed on the blue run is artificial. I had another "before" run that had that same shape, differing from the red run only in that the torque kicked up with the same delay as the blue, creating that little diamond-shaped gap. No idea what the cause of that delayed torque onset is but it doesn't seem to be related to the intake mod.] The power diff just from the Eventuri gets the Emira much closer to the Evora, with the torque only noticeably different over 4500 RPM.

Second, the Evora seemed to be limited to 6500. I was less confident about the Evora's system state (sport mode, dyno mode, etc.) than the Emira, which in contrast gave obvious indications that it "knew" it was on a dyno. The biggest tip off was a message that read "Test Mode activated. Parking Brake roller bench." The Emira went to what looks like ~6700 RPM, though torque was dropping fast enough at that point that peak HP wasn't helped much by the extra revs.

Third, stuff around 4500 RPM - that's where the Emira torque starts to drop off. The shop owner was watching the mixture, and believes the mixture is overly rich starting around that level and believes a leaner ECU map would "fix" the torque drop.

[EDIT]

Additional thoughts:

Test drive. I'm not sure I could say that the added power is super noticeable. I still feel a consistent, noticeable power bump at or just before 6000 RPM. I wonder if the map is slightly different when the Emira is in test mode because that bump is not at all apparent in either of the Emira traces. The power delivery still feels glitchy to me in the Emira - it seems a little debatable whether the traces bear that out. To my eye the Evora trace shows a noticeably smoother torque curve.

The Eventuri, if anything outperforms its advertising, at least in my case. Peak power difference looks to be over 20 HP, and is noticeable all across the RPM ranges that matter. The shop owner does a lot of tuning and was very surprised at how much difference an intake makes in this car.

[EDIT]

Intake noise is noticeably louder on the driver's side, especially with the window open.

How long did you have the Eventuri installed before doing the dyno run? The ECU is going to adjust to it over time. The power pull on mine feels very smooth, not glitchy at all. The power curve on mine matches the Evora's, with a lift at about 5,300 rpm, while yours shows a drop in that range.