A90 Supra MKV on the dyno

Moorman

Well-Known Member
First Name
Jason
Joined
Apr 3, 2019
Threads
3
Messages
77
Reaction score
63
Location
Carlsbad, CA
Website
photos.app.goo.gl
Car(s)
2020 Supra (RIP); 2021 Tesla Model 3 Long Range
I've seen claims form a FocusRS tuner that vdyno is grossly inaccurate because they used their dyno run as the log source, and it wasn't even close to what the dyno showed, therefore VD is worthless. Trying to hack the parameters in vdyno to get an accurate result misses the point & design of vdyno though, so it's not really the way to validate it. Not meaning to discredit the effort of Twisted Tuning especially since I agree that vdyno is pretty accurate, just illustrating the like for like comparison would be dyno-on-the-rollers vs VD-on-flat-pavement rather than trying to massage the input parameters in the app to get matching results.

I'm just about to start the process in the Supra, but here's how I validated vdyno when using my FocusRS. Repeatability was key to me, and this sated my skepticism enough to trust vdyno to feed the data junkie within.

First is the dynojet results of stock compared to tuned:

Second is the vdyno version of those same setups, two runs each (opposite directions, same stretch of road):

dynojet_stock-vs-StratE30r1.jpg
vdyno_stock-vs-StratE30r1.jpg
Sponsored

 

Waferz

Well-Known Member
First Name
Michael
Joined
Dec 21, 2019
Threads
14
Messages
379
Reaction score
310
Location
Louisiana
Car(s)
2020 supra launch edition, 1993 rx7
I've seen claims form a FocusRS tuner that vdyno is grossly inaccurate because they used their dyno run as the log source, and it wasn't even close to what the dyno showed, therefore VD is worthless. Trying to hack the parameters in vdyno to get an accurate result misses the point & design of vdyno though, so it's not really the way to validate it. Not meaning to discredit the effort of Twisted Tuning especially since I agree that vdyno is pretty accurate, just illustrating the like for like comparison would be dyno-on-the-rollers vs VD-on-flat-pavement rather than trying to massage the input parameters in the app to get matching results.

I'm just about to start the process in the Supra, but here's how I validated vdyno when using my FocusRS. Repeatability was key to me, and this sated my skepticism enough to trust vdyno to feed the data junkie within.

First is the dynojet results of stock compared to tuned:

Second is the vdyno version of those same setups, two runs each (opposite directions, same stretch of road):

dynojet_stock-vs-StratE30r1.jpg
vdyno_stock-vs-StratE30r1.jpg
Hacking up the parameters is necessary to make it accurate with any new platform that doesn’t have a profile and all dynos read differently and will give a different reading day to day. Most tuners adjust their VD settings to closely resemble the dyno they use in house. There is nothing wrong with using this tool if it’s adjusted properly, it’s been used for years in the evo community and gives relatively close results.
 

Moorman

Well-Known Member
First Name
Jason
Joined
Apr 3, 2019
Threads
3
Messages
77
Reaction score
63
Location
Carlsbad, CA
Website
photos.app.goo.gl
Car(s)
2020 Supra (RIP); 2021 Tesla Model 3 Long Range
Hacking up the parameters is necessary to make it accurate with any new platform that doesn’t have a profile and all dynos read differently and will give a different reading day to day. Most tuners adjust their VD settings to closely resemble the dyno they use in house. There is nothing wrong with using this tool if it’s adjusted properly, it’s been used for years in the evo community and gives relatively close results.
I think we're ultimately saying the same thing...without published aerodynamic figures (Cd & frontal area) there's no way to avoid estimating those profile settings. What I mean by 'hacking', logging while spinning the rollers which skips chassis aero drag altogether and then trying to tweak the profile to make the log produced during that run jive with what the rollers said.

In short, my view:
Dyno chart from rollers = good
Vdyno chart from (flat/level) street = good
Vdyno chart from rollers = bad

I only mean to contribute my effort in validating vdyno as a useful tool since it was brought up in post #293
For me the logs will be taken from a 3rd gear pull for a couple reasons, mostly the speed on public roads, and also the faster we're going the greater the error if our aero estimates are off.
 

Twisted Tuning

Well-Known Member
Gold Sponsor
First Name
Justin
Joined
Mar 10, 2019
Threads
26
Messages
1,236
Reaction score
1,548
Location
New York
Website
www.twistedtuning.com
Car(s)
2020 Supra, 335xi, 135i, TwinTurbo Mazda6
I think you guys are confused, as i wasn't using a V-dyno as a replacement. As i use and have a real dyno, lol. Someone asked about it, so i posted. Really, there was no hacking parameters. Frontal area is a fairly easy calculation and takes 10 seconds to figure out. Drag coefficient is a little more complicated, but can also be calculated or simply used a known value. The rest is gearing which is readily available.

All i did was plug the log into VD, adjust the temp to match the log, and change the weight to roller weight of the dyno. And it spit out virtually identical curve and numbers. the guys who said it was way off probably left the vehicle weight when using a dyno log, that isnt correct. no real hacking needed. put the info in, load the log. spits out the numbers. its an estimate, not absolute. And is all based off calculations (speed vs time) similar to dynos for the most part.

Anyway, like i said, wasn't posting VD saying its a replacement. but in my experience, as long as you don't fudge the numbers and are honest. its generally very close and something people can have fun with. in the end, trap speed and et is the best way to know approximate power. And even then its not perfect science.
 

65sohc

Well-Known Member
First Name
Ken
Joined
Mar 8, 2020
Threads
11
Messages
466
Reaction score
272
Location
Fresno, CA
Car(s)
65 GTO, 69 Corvette, 65 Corvette 427, 23 Corvette
So in the midst of all those youtubes I missed what, if anything, the MST intake gained. Was it any more than a simple HKS panel filter which supposedly is 5-9 hp?
 

Dannyvandelft

Well-Known Member
First Name
Danny
Joined
Jan 15, 2019
Threads
15
Messages
2,790
Reaction score
3,997
Location
44133
Car(s)
Ordered A91 edition Supra
So in the midst of all those youtubes I missed what, if anything, the MST intake gained. Was it any more than a simple HKS panel filter which supposedly is 5-9 hp?
I just assume an intake only adds noise. These days intakes are so well designed, aftermarket ones don't add any power, and sometimes even lose power.
They get you by "dyno proven gains" BUT that's a dyno run right after the battery has been disconnected and the car is running slightly richer while relearning fuel trims.
Just consider an intake like a catback. Noise only.
 

65sohc

Well-Known Member
First Name
Ken
Joined
Mar 8, 2020
Threads
11
Messages
466
Reaction score
272
Location
Fresno, CA
Car(s)
65 GTO, 69 Corvette, 65 Corvette 427, 23 Corvette
I agree. The stock air box has flow diverters which don't appear to be there for looks. I did install an HKS panel filter which showed a modest gain on a dyno from someone who is not selling the part which is always a plus.
 

Twisted Tuning

Well-Known Member
Gold Sponsor
First Name
Justin
Joined
Mar 10, 2019
Threads
26
Messages
1,236
Reaction score
1,548
Location
New York
Website
www.twistedtuning.com
Car(s)
2020 Supra, 335xi, 135i, TwinTurbo Mazda6
As I have said before, unless you're going beyond 650whp or so the stock airbox is sufficient. You could replace the pipe between the turbo and airbox. But replacing the full instake system is a waste of money below the power level i mentioned. But if someone wants to spend all that money for a sound change, to each their own.
 

65sohc

Well-Known Member
First Name
Ken
Joined
Mar 8, 2020
Threads
11
Messages
466
Reaction score
272
Location
Fresno, CA
Car(s)
65 GTO, 69 Corvette, 65 Corvette 427, 23 Corvette
It is interesting to gauge how restrictive a stock intake is by hooking up a manometer between the filter and the throttle body and measuring the amount of pressure drop which is, essentially, negative boost. I've done this on numerous vehicles. On my GT350 it was close to negligible, about 11" of water vs. 6" for the aftermarket system. On my Boss 302 the factory system was quite restrictive with a whopping 28" of water vs. 6" for aftermarket. I got a solid 10hp increase on back to back dyno runs.
 

Supraboi7

Well-Known Member
First Name
Johnny Boi
Joined
Jul 31, 2019
Threads
14
Messages
739
Reaction score
985
Location
NC
Car(s)
2020 Toyota Supra
Does anyone have a dyno graph comparison for stock vs catted downpipe? Interested in seeing if the power comes on sooner!
 
 




Top