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Those baseline graphs are another testament that '19+ models are tuned with a bit more power than previous MYs.
 

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Those baseline graphs are another testament that '19+ models are tuned with a bit more power than previous MYs.
I'm not sure that is the case. Looking around at the various Dynos for any of the 300HP models 2016+ has shown that the cars are putting down similar numbers to the wheels regardless of model year. Of course, dynos, octane, weather conditions all play role.

It all just confirms that the engines are underrated as listed.
 

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I'm not sure that is the case. Looking around at the various Dynos for any of the 300HP models 2016+ has shown that the cars are putting down similar numbers to the wheels regardless of model year. Of course, dynos, octane, weather conditions all play role.

It all just confirms that the engines are underrated as listed.
Well, yes. Dyno sheets can really differ based on many factors. I typically correlate the numbers to the location and temperature at least when the dyno has been done. I disregard a datapoint if I have reason to believe that delta on ambient temps were >20F. But again, not a solid "correlate-able" metric.
 

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Discussion Starter #44
Unfortunately I had to drive the car for about 30 minutes straight prior to it going directly onto the dyno for today’s pulls. Looks like the peak difference in the graph has it picking up about 10whp though it’s giving some back at other points in the rev range.This is a 20.8 lb loss of unsprung weight on the driven wheels.

I’ll get some contrasting graphs up soon.
the driveshaft goes on in a week. I’ll get an oil change before that install then run it again for the driveshaft numbers.
 

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Discussion Starter #45 (Edited)
For any other nerds following the unsprung weight reduction experiment, I’m trying to work out an anomaly.
On Monday, I dyno’d the car, looked at the runs on the screen as they happened then got my printed graphs at the front of the shop and left. All of the pulls on the printed graph looked higher than when I watched them in real time in the shop so I assumed they were subject to some sort of correction.
When I mentioned this today during the shop dyno runs, they said that the only difference would be in the shape of the graph because it’s compacted down on the physical copy. They also added that the monitor I was looking in the shop already showed corrected numbers.
So thankfully I have videotaped some of the last pulls on Monday and I have the screen shots to contrast versus the paper print out.
The lack of explanation for the discrepancy kind of taints the efficacy of my experiment. The shop guys are straight shooters and know the dyno software so I don’t know how it shifted.
Monday's pulls on the monitor (VS printed graph):
RWHP / RWTQ
307.66 (313.78) / 321.71 (328.11)
312.38 (318.59) / 309.27 (315.42)
307.52 (313.64) / 302.34 (308.36)
306.49 (313.73) / 301.23 (307.34)

When I was watching in real time, after it heat soaked, it was very consistent around 307RWHP.

Contrast that against my pulls on the same dyno today where the pulls were more or less all heat soaked and the numbers were showing gains in real time (on the monitor) and remained unchanged on the way to the printer.

RWHP / RWTQ
313.77 / 309.97
312.90 / 305.34
315.87 / 308.65
312.34 / 304.07

So it picked up roughly 7 peak WHP and torque wasn’t really impacted.
Monday monitor reading (before wheel / tire swap):
94150

today’s pulls:
94151
 

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When the Dyno pull is being made it's in STD, i.e. real-time, that Dyno on that day with those exact Dyno conditions. It has to then be converted to SAE, which normalizes the data so it can theoretically be compared from 1 day to another and Dyno to Dyno. SAE is typically what you get on the print out after it's been converted.
 

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Discussion Starter #47
When the Dyno pull is being made it's in STD, i.e. real-time, that Dyno on that day with those exact Dyno conditions. It has to then be converted to SAE, which normalizes the data so it can theoretically be compared from 1 day to another and Dyno to Dyno. SAE is typically what you get on the print out after it's been converted.
Yeah, that’s what I was thinking.
The rough takeaway is that you can “recover” about 1 WHP for every 3 lbS. of unsprung weight taken off wheels/ tires over the driven wheels.
 
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Yeah, that’s what I was thinking.
The rough takeaway is that you can “recover” about 1 WHP for every 3 lbS. of unsprung weight taken off wheels/ tires over the driven wheels.
I think that has always been the rule of thumb, yes. Nice to confirm it. 👍
 

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Discussion Starter #49
Because the driveshaft took too long to get to me (arrives tomorrow), I won’t be able to isolate its gains on the dyno. Megan LDP’s got here Sunday and just went on. I may do some pulls to show combined gains for those two mods.
 

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Discussion Starter #50 (Edited)
I have about 5 miles on the CZP aluminum driveshaft since installed. Early impressions:
More audible-it’s not really loud but you can hear it spin up when on the gas pedal from 38mph up to about 60 (haven’t gone over 60 yet). More direct/ responsive for sure. I can see where this would cut *some 10ths off of a 1/4 mile time. Butt dyno-really tough to discern between sensing urgency gains vs rotational mass related WHP recovery gains. I’m fresh off the noticeable bump up from the lower Downpipes. If those got me 30 at the wheels (guesstimate), I’m thinking the driveshaft is in the 5-6 range. More to come as I get seat time, hard runs and dyno pulls.
 
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2-3 tenths seems a bit optimistic. That is a massive gain. If it was really 2-3 tenths people would be better off with a driveshaft upgrade than exhaust or intakes. If the butt dyno is guessing 5-6hp, it's not 2-3 tenths.
 

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Discussion Starter #52
2-3 tenths seems a bit optimistic. That is a massive gain. If it was really 2-3 tenths people would be better off with a driveshaft upgrade than exhaust or intakes. If the butt dyno is guessing 5-6hp, it's not 2-3 tenths.
I have no doubt it’s a better mod than exhaust or intakes. Intended to impart that it’s clear to see how it saves time but not yet clear just how much extra oomph it frees up.
 

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I've looked at some ET reductions on well sorted car by swapping to a carbon fiber driveshaft and it was ~1-1.5 tenths on a car making over 500whp. For most non-drag racers, the ET difference will be negligible because there are too many other variables going on. I have no doubt you like it, I just didn't want someone to read this and think they're shaving 3 tenths of a second off their ET automatically. That's all. No harm, no foul.
 

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Discussion Starter #54
I've looked at some ET reductions on well sorted car by swapping to a carbon fiber driveshaft and it was ~1-1.5 tenths on a car making over 500whp. For most non-drag racers, the ET difference will be negligible because there are too many other variables going on. I have no doubt you like it, I just didn't want someone to read this and think they're shaving 3 tenths of a second off their ET automatically. That's all. No harm, no foul.
I’ll revise. It hits the dyno again Monday at 10am so I’ll have some post-LDPs, post-driveshaft numbers to throw into the mix at that point.
 

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Discussion Starter #56
Mustang owners lose more weight with a driveshaft swap (heavier OEM parts) and only gain the 2-3 10ths so my numbers from a 9 lb reduction on driveshaft were probably off.

https://www.hotrod.com/articles/drag-test-carbon-fiber-driveshaft-really-shave-et/

A guy on the thread below says “sold over 900 of them and can say without question you will drop .10-.25 seconds 1\4 mile. losing 25+lbs. of rotating mass in the driveline is huge and you can actually feel the difference in how quick it revs.”
aluminum driveshaft 1/4 mile question
Hellcats gain 2/10ths on a 30-100mph pull?
Aluminum Driveshaft DOES in fact improve performance
Aluminum driveshaft? - The Mustang Source - Ford Mustang Forums
 
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The general rule of thumb is 100 lb of weight reduction = 0.10 s lower ET in the 1/4 mile. That's pretty consistent and accurate.

Less easy to apply a global rule of thumb but, very roughly, an increase in 10 HP will lower your 1/4 mi ET by 0.1 s.
 

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After more seat time, I have noticed an increase in vibration. Not bothersome. Almost feels like exhaust "rumble".

I don't have a lot of seat time yet. Next is a highway trip.
 
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After more seat time, I have noticed an increase in vibration. Not bothersome. Almost feels like exhaust "rumble".

I don't have a lot of seat time yet. Next is a highway trip.
I noticed some of that when I did the rear subframe collars.
 
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