Possible to Dyno AUTOMATIC 06 Mustang GT w/o trans lock tune?

OctaneStreet

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I want to baseline my car before I add power. Is there any way we can dyno the car without having a special transmission gear lock tune? If I take O/D off, will the car be able to be dyno'd since it'll stay in 4th once the guy goes WOT? 4th is our 1:1 gear as well if I'm not mistaken which is why I'm wondering if this would work... If not, what are our options if any?

Thanks
 

Dino Dino Bambino

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If you want an accurate dyno result, the pull would need to be done with the transmission locked in 4th gear to prevent it from downshifting when the dyno operator goes WOT. The torque converter also needs to be locked up as any slippage would result in lower dyno numbers. If it's done right, the HP & TQ curves would look similar to those from a dyno run performed on a manual car.
 

OctaneStreet

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If you want an accurate dyno result, the pull would need to be done with the transmission locked in 4th gear to prevent it from downshifting when the dyno operator goes WOT. The torque converter also needs to be locked up as any slippage would result in lower dyno numbers. If it's done right, the HP & TQ curves would look similar to those from a dyno run performed on a manual car.

Dammit, I was hoping that wouldn't be the case... *Sigh alright thanks man.
 

DieHarder

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Hmmm...I have an auto (Lito tunes it) and said just put it in 3rd and romp on it. Seems to be able to tune fine using 3rd; at least that's been my experience. Of course by the time I get to redline I could go to jail for the speed but guess I've just been lucky so far. Two years since the tune and still running great.
Lito's the man.
 

Pentalab

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On a dyno, use 3rd gear. Watch out though. It will go from 600/750 rpm to 6250 rpm damned quick like...... and quicker still once the blower is installed.

You can't use 'drive' (unless software temp locks it into 4th).... otherwise it will just drop into 2nd gear, then wind up in 2nd, then 3rd, then 4th. (OD off) .

On a side note, since the car has zero wind resistance on the dyno, has anyone heard of anybody winding the car up in OD ? On paper, it would top out at 200 mph @ 6 krpm. I would not try it, the tires could explode, if not speed rated.
 

OctaneStreet

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Hmmm...I have an auto (Lito tunes it) and said just put it in 3rd and romp on it. Seems to be able to tune fine using 3rd; at least that's been my experience. Of course by the time I get to redline I could go to jail for the speed but guess I've just been lucky so far. Two years since the tune and still running great.
Lito's the man.

Yea I contacted lito as well to inquire about a tune and pricing. I plan to go to him in the future once I start adding more bolt ons. I think I'm going to just try dynoing it in 3rd... Really want to see what the numbers turn out to be haha, thanks for your input.
 

OctaneStreet

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On a dyno, use 3rd gear. Watch out though. It will go from 600/750 rpm to 6250 rpm damned quick like...... and quicker still once the blower is installed.

You can't use 'drive' (unless software temp locks it into 4th).... otherwise it will just drop into 2nd gear, then wind up in 2nd, then 3rd, then 4th. (OD off) .

On a side note, since the car has zero wind resistance on the dyno, has anyone heard of anybody winding the car up in OD ? On paper, it would top out at 200 mph @ 6 krpm. I would not try it, the tires could explode, if not speed rated.

Haha gotcha. 3rd gear pulls it is! Thanks for the insight. As for your dyno run using O/D off question, O/D actually kicked off for me when I wound it all the way out on a closed course one time. I was going maybe 150mph before it redlined and kicked me into 5th (it automatically put o/d back on). I wanted to see what would happen and that was the result. I know the wind resistance is a factor but I don't think 200mph would be reached tbh.
 

DieHarder

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Haha gotcha. 3rd gear pulls it is! Thanks for the insight. As for your dyno run using O/D off question, O/D actually kicked off for me when I wound it all the way out on a closed course one time. I was going maybe 150mph before it redlined and kicked me into 5th (it automatically put o/d back on). I wanted to see what would happen and that was the result. I know the wind resistance is a factor but I don't think 200mph would be reached tbh.

Ah, that's weird and shouldn't be possible unless there's a glitch/safety override you found in the software accidentally. Anyone else ever heard of such a thing? Anyway to look that up in the tune?
 

Pentalab

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Ah, that's weird and shouldn't be possible unless there's a glitch/safety override you found in the software accidentally. Anyone else ever heard of such a thing? Anyway to look that up in the tune?

I think what's happening is, even with OD OFF..and in 'drive', the 5r55s + a 3.31 rear gear, and 27" tall rear tires, the car will do 149.9 mph @ 6 krpm. OEM rev limiter is set to 6250 rpm. I got my tune from VMP. He re-tweaked the rev limiter to 6500 rpm. Shift points (gas mashed) were aprx 6 krpm. He unlocked the SCT-X3 such that I can tweak each shift point up /down on a shift by shift basis, like 1-2, 2-3, 3-4, 4-5. The car also has a speed limiter built into the oem FORD software tune, and it's set at 150 mph. What's supposed to happen is the eng is supposed to go into limp mode, with every 2nd cylinder's injector shut off, and ditto with every 2nd cylinder's spark plug.

VMP disabled the 150 mph max speed limit, so there is no max speed limit on my 2010 auto. One would think with the OD OFF, it would just hit the rev limiter, but apparently the OP sez his will shift into OD by itself. I have only had the car up to 137 mph, so can't test that theory.

JJR427 runs his 2010 auto (with roush M90 blower) on road courses. When the 5r5ss gets too hot, it will shift into OD (even with it off) at 70-120 mph. In OD, the rpm drops of course, and the idea is the tranny will be less likely to overheat.... it's trying to save itself.

In my case, I didn't like the rev limiter set to 6500 rpm, so reduced it in the SCT-X3. The next avaialble increment down from 6500 rpm is.... 6250 rpm, so set it for 6250 rpm. Fine, but noticed..twice now, when maxed out in 3rd gear, it would hit the rev limiter ! (instead of shifting to 4th). My 'fix' for that was to lower the shift point slightly for the 3-4 shift.... problem solved.

In JJR427's case, he had to install a 2nd tranny cooler. I also installed a 2nd tranny cooler, ( in series with the oem tranny cooler). These are the B+M type, 3/4" thick, and are bar + plate config...(instead of tube + fin). New cooler is installed right below the oem cooler. I had also installed a PA deeper pan, which is 10.5 lbs..and is exactly 2.1" deeper than oem steel pan. And also the JDM engineering catch can for the 5R55S. And also RP 'max atf' 100% synthetic ATF. With the deeper pan holding an additional 4 qts, I would have thought that would have solved my high temps on the 5R55S, it didn't.

With blower on, on the hwy, auto tranny temps (as indicated on the aeroforce digital gauges plugged into obd port, and gauges mounted on the SOS A pillar pod), the tranny temps would go from 170 F..to 200 F in a mere 5-8 seconds. After the 9700 BTU B+M cooler installed in series with the oem cooler, the temps only rise to 171..and sometimes 172 F.

But JJR427 still had a 5r55s overheating problem when on a road course, like during the 3rd session of the day. And he installed the even bigger 20,000 btu B+M cooler in series with the oem cooler. He had to cut out a chunk of the front bumper to get it to fit. With temps > 200F, the 5r55s will shift into OD ( even with OD off). I don't road course, so my 9700 BTU extra cooler, catch can, and deeper pan + synthetic is fine for my street use.

The wind resistance > 100 mph is wicked. And wind resistance goes up to the square of the velocity. 200 mph is quadruple that of 100 mph. So you can see why the car bogs down when > 125 mph. It's maxed out at 150-160 mph in 4th gear. In OD, the eng rpm drops like a rock, and not enough power left at the lower rpms, to overcome the wind resistance. It would never make it to 170-200 mph in OD.
 

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