Flexplate - Covid?
TECH Junkie
Joined: Jun 2008
Posts: 3,194
Likes: 1,377
From: Nitro Alley
I am sure most people do not put any thought into it what so ever...
The torque-converter (and more importantly the pilot) need to be properly supported.
And I do NOT simply mean being bolted to the flex-plate...
Pilot support and centering is crucial!
For one of you guys to feel something even slightly like the forces that act upon the torque-converter with no pilot support...
We would have to:
-Get one of those huge spinner wheels that used to be on TV game shows (one that is upright, not parallel to the ground).
-Get one of you strapped onto the spinner wheel with straps over each upper-arm and upper-leg.
-Get four 25 Lb weights.
-Putting one on each wrist and one each ankle.
-Lastly get one 3 Ft rope and a 50 Lb bar-bell weight.
-Finally, attach the rope and 50 Lb weight to the guy's D%$# and spin the wheel around as fast as about 6 guys can turn it at once!
That ain't gonna feel so good... Well that is your torque-converter without the pilot supported!
Simplifying things...
The torque-converter pilot needs to be supported and centered by the crankshaft to flex-plate flange (or for some OEMs the flex-plate itself).
The mass of the torque-converter on its own is substantial...
Add the forces placed upon it from spinning at engine speeds...
Lastly, the additional mass of the ATF inside the torque-converter and the FORCES it places further on it from centrifugal force.
Most people have NO idea how fast the crankshaft in an engine is actually turning...
Nor how fast transmission components can be turning in 1st gear for example (2,3, or even 4 times faster than engine speed).
A crankshaft with a 6 inch diameter, turning 6,000 RPM would be traveling at just over 100 MPH...
The direct drum in the 4L80e would be turning in the reverse direction at close to 250 MPH while in first gear.
The entire power-train drive-line needs to be in a relatively straight line (drive-shaft U-joints being slightly off a few degrees in most cases for loading).
The torque-converter pilot and body need to be supported properly and kept inline with the crankshaft.
Otherwise the run-out can cause bad vibrations, the pilot and crankshaft can become damaged, the flex-plate can crack or break apart, the torque-converter and transmission oil pump can be damaged or broken, the crankshaft and bearings will wear-out or spin-out, the transmission bearing and supported components will also wear-out, and even input-shafts can be broken...
The torque-converter (and more importantly the pilot) need to be properly supported.
And I do NOT simply mean being bolted to the flex-plate...
Pilot support and centering is crucial!
For one of you guys to feel something even slightly like the forces that act upon the torque-converter with no pilot support...
We would have to:
-Get one of those huge spinner wheels that used to be on TV game shows (one that is upright, not parallel to the ground).
-Get one of you strapped onto the spinner wheel with straps over each upper-arm and upper-leg.
-Get four 25 Lb weights.
-Putting one on each wrist and one each ankle.
-Lastly get one 3 Ft rope and a 50 Lb bar-bell weight.
-Finally, attach the rope and 50 Lb weight to the guy's D%$# and spin the wheel around as fast as about 6 guys can turn it at once!
That ain't gonna feel so good... Well that is your torque-converter without the pilot supported!
Simplifying things...
The torque-converter pilot needs to be supported and centered by the crankshaft to flex-plate flange (or for some OEMs the flex-plate itself).
The mass of the torque-converter on its own is substantial...
Add the forces placed upon it from spinning at engine speeds...
Lastly, the additional mass of the ATF inside the torque-converter and the FORCES it places further on it from centrifugal force.
Most people have NO idea how fast the crankshaft in an engine is actually turning...
Nor how fast transmission components can be turning in 1st gear for example (2,3, or even 4 times faster than engine speed).
A crankshaft with a 6 inch diameter, turning 6,000 RPM would be traveling at just over 100 MPH...
The direct drum in the 4L80e would be turning in the reverse direction at close to 250 MPH while in first gear.
The entire power-train drive-line needs to be in a relatively straight line (drive-shaft U-joints being slightly off a few degrees in most cases for loading).
The torque-converter pilot and body need to be supported properly and kept inline with the crankshaft.
Otherwise the run-out can cause bad vibrations, the pilot and crankshaft can become damaged, the flex-plate can crack or break apart, the torque-converter and transmission oil pump can be damaged or broken, the crankshaft and bearings will wear-out or spin-out, the transmission bearing and supported components will also wear-out, and even input-shafts can be broken...
TECH Fanatic
Joined: Jan 2015
Posts: 1,114
Likes: 33
From: Fort Worth, Texas
There's no issues running a flexplate spacer, plenty of people do it, so not sure why you're so against it.
If you're looking to go the cheap route, you can get an ATP Z-270 off Amazon for like $60. It's a flat flexplate that includes the extension. Or you can call a company like FTI and they can hook you up I'm sure with something decent.
FWIW I have a long crank lq4 and custom built 4l80e bolt pattern converter and run a flat SFI JW flexplate that has both a standard ls bolt pattern and 11.5" 80e pattern. You'd need to get a spacer since it's not included. Part number is 564-93019-LSC.
If you're looking to go the cheap route, you can get an ATP Z-270 off Amazon for like $60. It's a flat flexplate that includes the extension. Or you can call a company like FTI and they can hook you up I'm sure with something decent.
FWIW I have a long crank lq4 and custom built 4l80e bolt pattern converter and run a flat SFI JW flexplate that has both a standard ls bolt pattern and 11.5" 80e pattern. You'd need to get a spacer since it's not included. Part number is 564-93019-LSC.
Now, The factory spacers used on LQ4/4L80E combinations wearing is very common, Pick up a stock 4L80E converter & you'll understand why! A smaller/lighter performance converter won't beat up the spacer but needs to be checked if using a used one.