Ideal shift RPM for 10r80?

[Andy13186]

I had a tune that shifted at 7800 which I thought was a bit high since I could feel the power start to fall off near the shift. I have seen many dynographs with similar or the same mods as me (basically just an e85 tune) and it does look like peak power is almost always around 7000 rpm. Heres a pretty typical example.

My question is : using this dynograph what would the ideal shift points for every gear be? I think the ideal shift rpm would be higher in 1st and 2nd gear because they are a bit farther apart and RPM drops off more on the shifts, then lower for 3rd on up since they are closer together and peak power is around 7000 rpm. Is it possible to change shift points for individual gears?

The 10r80 ratios are 4.7, 2.99, 2.15, 1.8, 1.52, 1.28 1, .85, .69 and .64

Right now I am kind of thinking its like 7650 for 1-2 and 2-3 and 7500 or lower for the rest. Depending on how much torque actually helps on the 1-2 and 2-3.

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[EFI]

Based on that graph, I would shift at whatever RPM puts me to at least 5700 in the next gear, but no more than 7500.

 

[18 Smoke]

I had a tune that shifted at 7800 which I thought was a bit high since I could feel the power start to fall off near the shift. I have seen many dynographs with similar or the same mods as me (basically just an e85 tune) and it does look like peak power is almost always around 7000 rpm. Heres a pretty typical example.

My question is : using this dynograph what would the ideal shift points for every gear be? I think the ideal shift rpm would be higher in 1st and 2nd gear because they are a bit farther apart and RPM drops off more on the shifts, then lower for 3rd on up since they are closer together and peak power is around 7000 rpm. Is it possible to change shift points for individual gears?

The 10r80 ratios are 4.7, 2.99, 2.15, 1.8, 1.52, 1.28 1, .85, .69 and .64

Right now I am kind of thinking its like 7650 for 1-2 and 2-3 and 7500 or lower for the rest. Depending on how much torque actually helps on the 1-2 and 2-3.

7500 is ideal for NA E85 tune. Last year, my car went nearly 3 tenths faster shifting @7500 than it did shifting @7800 on back to back passes. 7500 keeps it right in the power band

 

[drive_55_not]

7500 is ideal for NA E85 tune. Last year, my car went nearly 3 tenths faster shifting @7500 than it did shifting @7800 on back to back passes. 7500 keeps it right in the power band

That;s what I've determined from my track testing, I set my shift light at 7250 and manually shifting nets the actual shift around 7550-7600, That nets my quickest and repeatable times.

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[18 Smoke]

That;s what I've determined from my track testing, I set my shift light at 7250 and manually shifting nets the actual shift around 7550-7600, That nets my quickest and repeatable times.

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My NA tune was AED and Shaun had it shifting@7500 on its own. Now I’m boosted PBD and Rob has it set @7800

 

[18GTmustang]

My NA tune was AED and Shaun had it shifting@7500 on its own. Now I’m boosted PBD and Rob has it set @7800

mine is set up to maybe 7800 rpms or maybe more on 1-2 2-3.. i do see the needle going all the way to 8k but i dont know the exact shift point.. the other gears are for sure set to 7800 or maybe little lower. N/A AED tune.

 

[18 Smoke]

mine is set up to maybe 7800 rpms or maybe more on 1-2 2-3.. i do see the needle going all the way to 8k but i dont know the exact shift point.. the other gears are for sure set to 7800 or maybe little lower. N/A AED tune.

Strange. Shaun said they don’t make power above 7500 NA w/ stock intake and my car was much faster shifting @7500

 

[18GTmustang]

Strange. Shaun said they don’t make power above 7500 NA w/ stock intake and my car was much faster shifting @7500

my first tune was Set to 7500.. then i asked him for the transbreak tune and to throw more on it If there was something left on it.. and i recieved that retune with rasied shift points and trans break ..
I do have a retune for long tube headers but ive been working long hrs so i dont have the time to take it to a shop to install them.

 

[18 Smoke]

my first tune was Set to 7500.. then i asked him for the transbreak tune and to throw more on it If there was something left on it.. and i recieved that retune with rasied shift points and trans break ..
I do have a retune for long tube headers but ive been working long hrs so i dont have the time to take it to a shop to install them.

I had the LTH on mine when he did my tune last year. It was with SCT BDX. I guess if it works for you, that’s all that matters. Did you run yours at strip with both tunes to compare?

 

[18GTmustang]

I had the LTH on mine when he did my tune last year. It was with SCT BDX. I guess if it works for you, that’s all that matters. Did you run yours at strip with both tunes to compare?

Negative. little after i retuned it i got rear ended. my car is fixed BuT like i said no time for anything due to work specially on a night shift schedule. Once i install headers and retune it ill check my shift points to see if he went back to 7500 or left it the same.. I wonder why shaun is not tuning Boosted 18s

 

[Zinc03svt]

Mine shifts @ 7400-7500 range and drops to 6400-6500 on each shift in sport/drag. Does not need to be any higher rpm wise w/ stock box/exhaust etc.

 

[Andy13186]

Mine shifts @ 7400-7500 range and drops to 6400-6500 on each shift in sport/drag. Does not need to be any higher rpm wise w/ stock box/exhaust etc.

According to the gear ratio calculator I used here: https://spicerparts.com/calculators/transmission-ratio-rpm-calculator and the stated trans gear ratios posted above in the OP ;

When shifting at 7500 from 1st to 2nd the RPMS should theoretically drop to below 5000.. But in my logs this never happens possibly due to wheel spin?

Shifting at 7500 from 2nd to 3rd the RPMS should drop to 5400.

But 3rd to 4th and onward at 7500 and they should drop to 6200+.

This is why I think the ideal shift point may be really high for 1-2 and 2-3 and 7500 or even lower for the rest. In my logs the 1-2 never drops below like 6000 though, but I almost always get wheel spin on that shift so its hard to know whats accurate or best.

I also dont know if I am excluding some characteristic of torque converters during shifts. I also dont know if dropping into more hp but less torque could help prevent wheel spin?

Does anyone know if its possible to change individual gears shift points?

 

[Idaho2018GTPremium]

See if you can create a torque thrust graph from your dyno. That will tell you how much torque is being applied by the rear wheels in each gear. You can then tell where your thrust is at the top of your rpms, and where it will be when you shift, etc.

 

[stanglitt]

See if you can create a torque thrust graph from your dyno. That will tell you how much torque is being applied by the rear wheels in each gear. You can then tell where your thrust is at the top of your rpms, and where it will be when you shift, etc.

I made a spreadsheet more many, many years ago to showcase this. I'll see if I can find it and plot in the data from the torque curve from OP's post. Tbh, it looks to me as if the torque drops off a little too fast to fully take advantage of the high-revving gen3 engine, but let's see... be back with an update if I manage to find the document...

 

[stanglitt]

I made a spreadsheet more many, many years ago to showcase this. I'll see if I can find it and plot in the data from the torque curve from OP's post. Tbh, it looks to me as if the torque drops off a little too fast to fully take advantage of the high-revving gen3 engine, but let's see... be back with an update if I manage to find the document...

Here we go...

So the ideal shift point is at 7500ish RPM (maybe higher; can't tell from the blue RunFile) for 1st, 2nd and 3rd. 7250ish RPM after that because the torque drops off a tad too fast to make it worthwhile to wait till 7500. Then of course there's the 9th-10th shift but not really relevant...

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