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OK, just to recap
My original post was to comment on Markys posts with his 3rd decimal point usage making it hard, for me at least , to read the post.

I accidently
Type the digit 5 instead of 6.
You insert yourself in to correct me.

I make mention of the ratios in my one year only SSR T56 transmission

You suggest I am mistaken and have a TR6060 and somehow insert your feelings towards the LGBT .

I give more clarification

You regurgitate a published trans chart which does not include the 06 SSR T56 I am speaking of.

We can argue the .56 or .57 all day,
Don't think it matters but the tooth counts in my t56 and my grade school "learnin" has me rounding up to .57
 

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Discussion Starter #22
So anyway, Thanks to Mark for some good starting points regarding shift tuning for 2.56 rear gears. In the realm of significant figures 2 digits is close enough for my shade tree shop.

-Brian
 

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So anyway, Thanks to Mark for some good starting points regarding shift tuning for 2.56. In the realm of significant figures 2 digits is close enough for my shade tree shop.
You're welcome. Just 'cause 2.5625 ( 🧐 🤪 ) is not a gearset meant for typical ISSF enthusiasts, doesn't mean ALL hope is lost - only some hope, specifically, the hope of respectable acceleration compared to 3.42 & better axle gearing.
It's PAINFULLY obvious that GM's GM8 shift table was not written with ANY interest in protecting the LT1 the 4L60E or the driver from unnecessary excessive shifts - or wear, or rebuilds.

Moreso with GM8 than better axle gears:
the shift table should be written so well that it would be a good idea to physically lockout 'D' '2' & '1'
gross laden weight and aero drag critically affect tuning the GM8 shift table to protect the powertrain
 

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All the above said, however, I know of a minority of (ISSF) drivers who are happy with GM8.
To them I say:
the shift table can and should be improved
either way I truly hope you enjoy it

Ultimately, though, for most the rest of the LT1 B-car enthusiasts, the real question becomes:
GT4 vs GU6​
Lesser axle gearing always was is and will be a compromise / net loss for the driver.
 

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You suggest I am mistaken and have a TR6060 and somehow insert your feelings towards the LGBT .
Humor is often the juxtaposition of incongruities, like transphobic/transmission/trans. This in no way illuminates my feelings toward the LGBT, though I see no reason not to joke about it. Blasphemy? Politically incorrect?
no one can call me trans hater.
This was my comment on a thread that had obviously gone off the rails. My fault, in more than one way.
I admit I do not understand how offense could taken, but if it has been, know it was not meant to be offensive, just funny.
You have established that in this thread I was not funny.
 

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Discussion Starter #26
I have just finished my first drive with the new axle. D/S took a week to get shortened. The howling grinding noise is gone. Now I can hear just how missing the door seals/sheet metal is on my cab...

I have some serious tuning of the shift tables to do still. Didn't get much over 45 so it stayed in 3rd for most of the drive, couple spots where it was downhill coasting and what not it momentarily skipped into 4th. Need to raise the MPH for 4th a little bit at very light throttle to make that behavior stop. I've got it shifting up too early so I need to raise the MPH across the board and try again tomorrow.

I did make myself a little excel spread sheet to show the shift points as as a function of current and next gear engine RPM and it did help my manual rowing brain make more sense of the shift points. Thinking in terms of MPH when I have never previously driven the car was not gelling very well in my head.

-Brian
 

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Discussion Starter #27
Does it make sense to start using the ability to lock up in 2nd gear at part throttle, lower speed cruising? Like cruising through 35mph streets, is for sure in 2nd gear but its second gear at almost 2k RPM. I think I could use lock up at this point and hold the RPM down without lugging and cut the extra heat build up the TC causes.

Still not sure what to do about 40mph streets. It's third gear at 1600rpm with the TC unlocked but drops to 1250rpm locked. At 13% throttle needed to maintain speed it just feels like it's not quite enough RPM. Like it would be happier unlocked, but that would be bad for temps. But second gear locked would be 2100 rpm which seems too high for part throttle cruising.

-Brian
 

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Assuming level ground - cruising @ 35MpH in 3rd, with the TCC unlocked, is to up to your taste.
Cruising at or over 32MpH, I preferred 3rd over 2nd, so long as I had 5 or less riders in my wagon.
Under 19% throttle is almost never enough load for concern on level ground.

Depending on tire size, I'd hesitate to lock the TCC in 3rd under 45MpH, and I'd unlock it under 40MpH on decel, but with very light loads it can be done. Once you per-féct the shift table, then maybe lock it in 3rd at low loads / throttle angles.

With GM8-2.563, 1st is for hardest accels <40MpH, 2nd is for most accels <90MpH, 3rd is for cruising at or over 32MpH (and maybe imperceptibly mildly accelerating Miss Daisy).

Locked TCC in 2nd feels very odd & weird; can't recommend it, even cruising <28MpH at low TPS%.

If you're concerned with ATF temps:
LubeGard Red / Platinum / Complete Full Synthetic
redirect shove or pull more air thru the ATF cooler
upgrade the ATF cooler
stop routing ATF through the radiator sidetank(s), except maybe during the winter
upgrade to GU6-3.42 or GT4-3.73. It's both a performance mod AND a maintenance upgrade!

(For perspective, study an OEM LT1 2.563 .bin file's normal shift table. Your eyes'll cross.)
 
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