N52 intake shootout

[digger]

Not Dynojet, it's a magneto-resistance one that's supposedly calibrated to match Dynojet (there's a Dynojet up the road and they say cars are the same on the two)
Nice thing about this one is it's perfect for holding part-throttle load for data logging and fuel corrections.

We werent holding it that long because it was pointless.

when you get things sorted just put it on an actual dynojet for some numbers that mean something in an absolute sense when said and done, operators are always talking BS. when they say calibrated to a dyno jet they just mean they fudging numbers which makes them kind of useless as the differences between dynos change depending on which vehicle is used as the "calibration" and you cant calibrate the curve just to a peak so very easy to create a random number generator. The other thing to is check how they are getting the rpm signal and that it is correct as that can skew torque

[hoveringuy]

The other thing to is check how they are getting the rpm signal and that it is correct as that can skew torque

Yeah, It noticed that as well, Dynojet always has a pickup to get actual motor RPM, this one uses a scaling factor to convert roller speed to tach rpm, so the best they do is hold it at 2000 and make sure the tach matches the display.

This dyno is valid for the moment as an "apples to apples" comparison of the same motor on the same dyno with different configurations, but when I get it done Ill need to throw it on the Dynojet to get numbers that can be compared to other Dynojet numbers.

[digger]

Yeah, It noticed that as well, Dynojet always has a pickup to get actual motor RPM, this one uses a scaling factor to convert roller speed to tach rpm, so the best they do is hold it at 2000 and make sure the tach matches the display.

This dyno is valid for the moment as an "apples to apples" comparison of the same motor on the same dyno with different configurations, but when I get it done Ill need to throw it on the Dynojet to get numbers that can be compared to other Dynojet numbers.

it doesn't matter if provided they did it same way for both runs for a comparison.

i always ask for a road speed graph as well so i can work out the rpm to speed conversion as the tacho might be a bit off depending on the rpm and i get a better rpm number from the ECU.
i just don't trust the operator as i have seen them stuff it up and use a different scale factor for baseline vs the after run when nothing changed which makes comparisons of graphs with rpm as Y axis useless

[hoveringuy]

it doesn't matter if provided they did it same way for both runs for a comparison.

i just don't trust the operator as i have seen them stuff it up and use a different scale factor for baseline vs the after run when nothing changed which makes comparisons of graphs with rpm as Y axis useless

LOL, either do I! I had him go to the old run and copy the scaling factor, otherwise would have been garbage comparison.

[hoveringuy]

So I replaced both DISA valves and the car pulls much stronger on the top now.

I took it to a Dynojet for a baseline to get an apples to apples with all of the other Dynojet data moatilliatta . 243STD/235SAE isn't bad but it's not great either. Keep in mind, this is basically untuned and hasn't been optimized. A/F is fat at 12.

[moatilliatta]

So… 22rpd 30hp high?

[hoveringuy]

So… 22rpd 30hp high?

It seems like theyre off more on the low end. If Luke made 248 to my 268 in the same configuration thats 20, but I figured 10%.

Ill know better when I do another baseline in a few weeks at 22RPD when I fix fueling.

I think it probably also has a lot to do with improper RPM at 22RPD, the Dynojet has a pickup and RPM is exacct, 22 just kinda matches the tach with the rollers for something that's kinda close.

[moatilliatta]

What are they using? dynocum?

It’s not hard to pick up signal to the coil.

What do they use for wideband or do you log with on the wideband?

[hoveringuy]

What are they using? dynocum?

It’s not hard to pick up signal to the coil.

What do they use for wideband or do you log with on the wideband?

My upstream sensor are Wideband, obviously, but I'm not currently logging, although I know there's an application that will do that.

When they tune the fuel they run it steady-state at a bunch of different speeds/loads and log the ECU correction. Correct the fuel table and repeat until ECU corrections are close to zero. I think there will be several rounds of tuning, starting with getting the fuel right and then timing of both ignition and VANOS.

My understanding of the full throttle is that the ECU makes corrections in real-time to match the A/F table which is mostly 13.0 so I don't know how that's tuned.

I'll get dyno details next time I'm there.

I think the 10 percent discrepancy is more of a "move the graph right' because I'm probably doing at 3000rpm what they think I'm doing at 2700, or something like that.

[varg]

Usually you can get an optical tachometer close enough to the crank pulley to read with the appropriate marking placed on it, and use that to verify the accuracy of the car's tach. I've done this before myself, and it seems prudent for dyno operators to have one on hand in the unfortunate circumstances where someone doesn't have the ability to plug in and display actual engine RPM with tuning software or even OBD

[hoveringuy]

Usually you can get an optical tachometer close enough to the crank pulley to read with the appropriate marking placed on it, and use that to verify the accuracy of the car's tach. I've done this before myself, and it seems prudent for dyno operators to have one on hand in the unfortunate circumstances where someone doesn't have the ability to plug in and display actual engine RPM with tuning software or even OBD

I have and OBD with the rpm signal, or they could alternately use an inductive pickup.

so many ways...

I think they're more focused on the before-after rather than absolute accuracy which is fair.

[wazzu70]

Is 22RPD doing the tuning?

looking forward to seeing the results of the new mani with the DISA valves fixed and tuned for proper comparison.

This engine is very appealing!!

[hoveringuy]

Is 22RPD doing the tuning?

looking forward to seeing the results of the new mani with the DISA valves fixed and tuned for proper comparison.

This engine is very appealing!!

Yep, this is 22RPD.

This is my run with the new DISA valves plotted against LukeJ 's motor with the N54 intake. The differences are that he's running a single (troublesome...) cat and his exhaust is slightly different. Neither motor is completely optimized for the configuration yet with room for improvement in the tune. Obvious takeaway is that the DISA intake makes more torque and the N54 carries power higher. I'll also throw-up an S52 plot below. I think the shape of the torque curves are interesting; even though the S52 has more displacement it doesn't match N52 torque until at least 4000. At 3000 it it's not even close. At 4500-5500 the S52 must feel like a beast.

[digger]

So I replaced both DISA valves and the car pulls much stronger on the top now.

I took it to a Dynojet for a baseline to get an apples to apples with all of the other Dynojet data moatilliatta . 243STD/235SAE isn't bad but it's not great either. Keep in mind, this is basically untuned and hasn't been optimized. A/F is fat at 12.

these make more sense, there was no reasonable explanation as to why it would have made so much more than other N52's other than a small improvment being realised due to the e30 chassis with less rotational inertia in the driveline

[hoveringuy]

Update! First track day of the season yesterday. It felt more like a "back in the saddle" event, and I spent most of the time getting used to my boosterless, dual-master cylinder balance bar brakes. My overall times were a few seconds off my personal best at this track, but my end of straight speed got to within 0.9 mph of my previous top speed there. Another event or two and I'll match the speed with a little better exiting out of the straight entry corner and hold the throttle slightly longer as I get used to the brakes.

Bottom line so far is no major difference in times from the N54 intake, biggest difference is that I can't wind it out to 7500 like before because power starts to wain after 6800, whereas it never really peaked with the N54 intake.

A guy with the supercharged E46M3 came up to me in the paddock and wanted to know why he couldn't catch me, with his 400+whp and all....