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View Full Version : 2017 Dyno results/upgrades



Jacob_Royer
04-16-2017, 02:23 PM
Last year power was up a little from when Dave initially (279rwhp/12.70@107.7)tuned the car but still was not where i wanted it to be:


http://i20.photobucket.com/albums/b250/jacobroyer/Mobile%20Uploads/20170415_130052_zpsswnudavo.jpg (http://s20.photobucket.com/user/jacobroyer/media/Mobile%20Uploads/20170415_130052_zpsswnudavo.jpg.html)

This year i upgraded to the Magnum powers abradive rotor pack and went from 33% od to 25% od. Also discovered a crack in the MPX case and it had trashed the last set of rotors and beat up the inside of the case pretty bad so i replaced it with a fresh mpIII Boost was still low IMO 12/13psi which was the same i saw with GTP rotors and 33% od. The other day i discovered a large crack in the back of my raised top! I had taken this off a parts car and just threw it on when i put the 4.2 in two years ago. I threw a stock top back on and instantly went to 16psi! The car felt much better but the tune was lean above 2.9v vmaf. After some runs and adding fuel i had it back into the realm of being safe. Saturday i took the car to Blakenship tuning for their annual spring dyno day. Here are the results! Note: This is a mustang dyno not a Dynojet like what i had the car on at the shootout so gains are likely alot higher.

http://i20.photobucket.com/albums/b250/jacobroyer/Mobile%20Uploads/20170415_124619_zpsru19qhec.jpg (http://s20.photobucket.com/user/jacobroyer/media/Mobile%20Uploads/20170415_124619_zpsru19qhec.jpg.html)

Lee Blakenship told me that i am blowing through the converter pretty badly and highly recomended re-stalling it so i am going to try to do that this year. The stall speed is 3500+ now where it was originally meant to be 2800rpm! the converter was built for a very mild 3.8 and has always stalled higher with the 4.2 but now its kinda silly on stall speed. The car feels alot better than it ever did and i hope be in the lower 12s this year

20psiofevil
04-16-2017, 07:31 PM
Where does the converter flash to now on the street? Was the converter locked? Nice gain from sorting out the issues.

Jacob_Royer
04-16-2017, 07:53 PM
Where does the converter flash to now on the street? Was the converter locked? Nice gain from sorting out the issues.


I have a non locking setup and it flashes around 3500

KMT
04-16-2017, 09:24 PM
I have a non locking setup and it flashes around 3500

Are you sure it isn't following the build trend and doesn't have cracks of it's own ;)

David Neibert
04-17-2017, 01:15 PM
So what are the new numbers ? Dyno sheet is hard to read.

David

Jacob_Royer
04-17-2017, 05:38 PM
http://i20.photobucket.com/albums/b250/jacobroyer/Mobile%20Uploads/20170415_104029_zps5uarehhi.jpg (http://s20.photobucket.com/user/jacobroyer/media/Mobile%20Uploads/20170415_104029_zps5uarehhi.jpg.html)QUOTE=David Neibert;1108792]So what are the new numbers ? Dyno sheet is hard to read.

David[/QUOTE]

20psiofevil
04-17-2017, 07:26 PM
I have a non locking setup and it flashes around 3500

Jacob not trying to nit pick but how is 3500rpm flash stall blowing through the converter? If anything it seems a bit tight for the combo?

Jacob_Royer
04-17-2017, 10:50 PM
Jacob not trying to nit pick but how is 3500rpm flash stall blowing through the converter? If anything it seems a bit tight for the combo?

Not at all its way too much stall for 3.73/wide ratio/m90

CMac89
04-18-2017, 09:03 AM
Not at all its way too much stall for 3.73/wide ratio/m90

I entirely disagree with that. That thought's a plague that needs to go away from SC land so y'all can be faster.

That's at least the stall you need to perform well. A different point/topic to make could be that there's too much total slip (not to be confused with stall speed) after the drivetrain speed catches up to the converter's drive speed. "Blowing through a converter" means that the stator can't hold the forces being applied by the converter pump, i.e. making too much HP for the design of the converter. If you're stopping at 3500 that means that your new power level was higher than originally intended, but that's one way to 'loosen' up a converter is an increase in power. Just as long as you don't have a lot of high speed slip.

David Neibert
04-18-2017, 01:20 PM
Jacob,

Mine is supposed to be a 3500 stall too and it will flash to around 5400 which usually makes getting traction off the line very difficult (even with slicks). It hits very hard when you go WOT, but I think it would be a lot more enjoyable to drive on the street if it was about 500 rpm tighter.

66985

David

Jacob_Royer
04-18-2017, 01:56 PM
Jacob,

Mine is supposed tois very be a 3500 stall too and it will flash to around 5400 which usually makes getting traction off the line very difficult (even with slicks). It hits very hard when you go WOT, but I think it would be a lot more enjoyable to drive on the street if it was about 500 rpm tighter.

66985

David



This gives me hope! It looks like our boost to hp ratio Is very simliar I just need a blower that will put 20psi to my junk! I am
planning on doing a 2.1l kenne bell once I sell the Cobra.

20psiofevil
04-18-2017, 06:41 PM
Not at all its way too much stall for 3.73/wide ratio/m90

A 373 gear ratio will actually soften the hit on the converter. The lower numerical gear ratio makes the converter work harder. My flash stall increased from 5200 to 5400 rpm just by switching from a 26" to 28" tire. Turbocharged though so load plays a bigger role on my boost curve.

Jacob_Royer
04-18-2017, 09:21 PM
I would be happy with it stalling around 2800rpm like it did with my old motor.

CMac89
04-19-2017, 04:40 PM
Jacob,

Mine is supposed to be a 3500 stall too and it will flash to around 5400 which usually makes getting traction off the line very difficult (even with slicks). It hits very hard when you go WOT, but I think it would be a lot more enjoyable to drive on the street if it was about 500 rpm tighter.



That explains part of why she runs so well :)

David Neibert
04-19-2017, 05:45 PM
That explains part of why she runs so well :)

Yeah...I'm not really unhappy with how high it flashes when I'm at the track, just feels a little too slippy when cruising around and generates more heat than I like. I think 3000 stall that flashed to around 5000 would feel much better and run a little cooler.

David

CMac89
04-20-2017, 09:17 AM
Yeah...I'm not really unhappy with how high it flashes when I'm at the track, just feels a little too slippy when cruising around and generates more heat than I like. I think 3000 stall that flashed to around 5000 would feel much better and run a little cooler.

David

I can understand that for sure. What converter do you have? Companies like PTC, Circle D, M&M, Coan and so on have mechanical lock up features that increase efficiencies of converters, thus reduced heating. Sometimes I wonder if money isn't invested into high efficiency AOD converters then that motivates people to use sub-par stall speeds that sacrifice performance that doesn't necessarily adversely affect streetability.

Kurt K
04-20-2017, 06:03 PM
Congrats Jacob.

Just to pile onto the converter discussion. I essentially have the same convertor as Neibert (or he has the same as me, I had mine first:p). I love it at the track, but I too think I need to tighten it up a bit. It is also the reason my car performs well at the track, but sucks on a dyno. Since this is the first transmission I have had that has lasted, I'm afraid to change anything.

sanddune24
04-20-2017, 09:41 PM
I can understand that for sure. What converter do you have? Companies like PTC, Circle D, M&M, Coan and so on have mechanical lock up features that increase efficiencies of converters, thus reduced heating. Sometimes I wonder if money isn't invested into high efficiency AOD converters then that motivates people to use sub-par stall speeds that sacrifice performance that doesn't necessarily adversely affect streetability.


Circle D doesn't advertise a converter for an AOD on their website but they do make them. Great converter in my opinion.

Jacob_Royer
04-21-2017, 01:08 AM
Congrats Jacob.

Just to pile onto the converter discussion. I essentially have the same convertor as Neibert (or he has the same as me, I had mine first:p). I love it at the track, but I too think I need to tighten it up a bit. It is also the reason my car performs well at the track, but sucks on a dyno. Since this is the first transmission I have had that has lasted, I'm afraid to change anything.



Mine is a 9" billet dirty dog 31spline (I have the billet input shaft). It will make you cry when you dyno the car lol.
I only made 213rwhp when it was running 13.70s and at 289rwhp i was going 12.70/107.7 i love how it does on the track
But it is really loose on the street. Mpg is beyond crappy I get 12ish lol i hope to see a low 12 this year!

XR7 Dave
04-21-2017, 07:51 AM
I think you guys are confused. Nobody's converter here flashes that high. Sure it jumps to 5000rpm pretty quick on the dyno, but that is because you are already in 3rd going 50mph when you try to lock it up AND it's probably slipping the tires to boot. You all need to datalog your cars AT THE TRACK before starting these conversations. My 5.0 "flashes" as you say on the dyno to about 4800rpm, and anytime you mash the throttle on the street it hits 3500rpm instantly, but at the track with slicks on and from a stand still it flashes/stalls at 2800rpm. Period. You can't make it go over 2800rpm without moving the tires first.

Not saying some of you couldn't use lower stall speeds, but suggesting that it would be helpful to use correct terms correctly and to be quote actual data rather than perceptions based on fluid conditions. I don't think the converters are eating up as much HP as you guys seem to think either. Brian Whitfield's 4.2 routinely makes 380+rwhp through his AOD and runs low 12's. He has a loose converter too. There are others as well.

Wzenheimer
04-21-2017, 09:29 AM
I would be happy with it stalling around 2800rpm like it did with my old motor.

You say this for the same reason Neibert says this:


Yeah...I'm not really unhappy with how high it flashes when I'm at the track, just feels a little too slippy when cruising around and generates more heat than I like. I think 3000 stall that flashed to around 5000 would feel much better and run a little cooler.

David

And like Dalke said being on a Dyno is way different than at the track on Slicks.

Jacob_Royer
04-21-2017, 10:53 AM
You say this for the same reason Neibert says this:



And like Dalke said being on a Dyno is way different than at the track on Slicks.



This is why my next tranny will be a 4r70w lol

Kurt K
04-21-2017, 03:16 PM
I think you guys are confused. Nobody's converter here flashes that high. Sure it jumps to 5000rpm pretty quick on the dyno, but that is because you are already in 3rd going 50mph when you try to lock it up AND it's probably slipping the tires to boot. You all need to datalog your cars AT THE TRACK before starting these conversations. My 5.0 "flashes" as you say on the dyno to about 4800rpm, and anytime you mash the throttle on the street it hits 3500rpm instantly, but at the track with slicks on and from a stand still it flashes/stalls at 2800rpm. Period. You can't make it go over 2800rpm without moving the tires first.

Not saying some of you couldn't use lower stall speeds, but suggesting that it would be helpful to use correct terms correctly and to be quote actual data rather than perceptions based on fluid conditions. I don't think the converters are eating up as much HP as you guys seem to think either. Brian Whitfield's 4.2 routinely makes 380+rwhp through his AOD and runs low 12's. He has a loose converter too. There are others as well.

Just to make sure I'm using the correct terms and not confusing anything, I assume that rpm and mph are used to determine when the tires start to move (I also compared TP to see when I started the race). If that's the case, mine doesn't move until something greater than 3972 rpm and less than 4296 rpm. If there are different parameters required, please let me know so I log the best information. I imagine if I could measure driveshaft rpm, that would be a better way to see what the converter is doing.

David Neibert
04-21-2017, 04:59 PM
Maybe "flash" isn't the correct term for what I was describing. It's supposed to be 3500 stall with direct drive deleted, same as Kurt's from Alan Brown. I can hold the brakes real hard and get close to 3300 rpm before tires start spinning or pushing the car forward. When hitting it hard from idle it's instantly at 5400-5500 rpm but tires are also spinning so maybe they spin at 3500 and just bust the tires loose causing it to spike up to 5500. Either way it's annoying because it feels too slippy when cruising. The 3500 stall converter in my old turbo car felt much less slippy cruising and I could get it up to 3300 rpm on the trans brake. It was also made by Alan but that transmission and converter was built to handle a lot more power.

David

20psiofevil
04-21-2017, 06:50 PM
Foot braking you cant get full flash stall because most of the time the brakes wont hold the power back. Now if you're on a trans brake, full throttle, boost, and power, rpm is going to go way up there. With that said my flash or stall speed is what ever I have my 2 step to:D

Jacob_Royer
04-21-2017, 07:42 PM
If i didn't love how my art carr VB shifts i would be all over a trans-brake full manual valve body

XR7 Dave
04-22-2017, 07:12 AM
Kurt, you are perceiving correctly. True stall speed isn't a fixed #, it does vary based on load and leverage and for most of us at the track, datalogging speed sensor activity vs. rpm is our best indicator. Part of fixing an incorrect stall speed is knowing exactly what stall speed you are seeing under the most ideal of conditions you can generate. In other words, track-trans brake stall rpm doesn't matter if you don't actually have or use one. And yes, you can break your converter if you try to make it stall with a trans brake higher than it is capable of holding.

The other thing you need to know, if you think you are "blowing through" the converter, is what % of slippage you are seeing at WOT and peak rpm. I know mine has 13% slip at 6000rpm in 3rd based on my best estimates. It's high, but it's not unusual and it's consistent.

I agree that if you have a converter that stalls even at the perfect rpm for drag racing use but you only drag race 2x a year then you are likely going to miss the mark and should compromise with a lower stall speed. For some of you if your converter really stalls that high then you probably can't even use overdrive on the street without basically cooking your transmissions or at least the fluid every 500 miles. Transmission fluid has a surprisingly short life when taken over 180 deg.

Kurt K
04-22-2017, 08:58 AM
The other thing you need to know, if you think you are "blowing through" the converter, is what % of slippage you are seeing at WOT and peak rpm. I know mine has 13% slip at 6000rpm in 3rd based on my best estimates. It's high, but it's not unusual and it's consistent.

So to calculate slippage, you would need to use the speed sensor and calculate the driveshaft speed based on gear ratio and tire size? Or am I missing something?

XR7 Dave
04-23-2017, 07:42 AM
So to calculate slippage, you would need to use the speed sensor and calculate the driveshaft speed based on gear ratio and tire size? Or am I missing something?

First thing you need to do is calibrate your BE calculator for mph logging against your GPS, then datalog a full throttle 1/4 mile run and calculate effective rear end gear ratio vs. theoretic. The difference is your slip %.

Kurt K
04-23-2017, 10:41 AM
First thing you need to do is calibrate your BE calculator for mph logging against your GPS, then datalog a full throttle 1/4 mile run and calculate effective rear end gear ratio vs. theoretic. The difference is your slip %.
So is that a table in BE? I knew something had to change since my 11.52 datalog only shows 103 mph and I know it was 118. When I replace the 103 with 118, I calculated about a 15% loss. However, I can see that have BE calibrated will be a lot easier than digging out all of my timeslips.

XR7 Dave
04-24-2017, 07:33 AM
You have to do the run with street tires. This is also why you have to calibrate the speed sensor against your GPS. You need instantaneous speed and full load at the proper speed. With 1/4 mile slips 1) they are often wrong), 2) it's a calculated average speed, not instantaneous, and 3) race tires grow quite a bit at 100+ mph.

Kurt K
04-24-2017, 09:49 AM
You have to do the run with street tires. This is also why you have to calibrate the speed sensor against your GPS. You need instantaneous speed and full load at the proper speed. With 1/4 mile slips 1) they are often wrong), 2) it's a calculated average speed, not instantaneous, and 3) race tires grow quite a bit at 100+ mph.I'm aware of all of those factors, but knew it would be closer than the 103 mph that BE was showing. Went on a cruise yesterday and my BE reads a full 10% less mph than GPS mph (my speedometer was somewhere in between). Now I just need to figure out where to modify BE.

Jacob_Royer
04-25-2017, 03:09 AM
I've been wanting to get to the track. It rains everytime the track is open lol I really need to see
where I am at. I hope my newfound power will squeeze a low 12 out of it. I am wanting to run
the 12.0 Index at the street car takeover on the 7th