I'm looking at rebuilding a 4L80E to hold 1100hp. My car is a 3700 lb street car 2000 camaro and I don't want every shift on the street to snap my neck. I do however want firm shifts when going all out with the car. That being said, I want this transmission to live and will be launching it at the track from time to time with no transbrake. I'm considering the CK Steel billet main shaft 4l8CC/BMS-1L and the forged steel billet rollerized hub 4L80CC/BFCH-A as 2 main upgrades. I'm also considering the 4L80ECC/MSRK kit. I see there's alot of stuff posted online to improve the performance of the trans, and was wondering if I shoud perform the following modifications as well in addition to the above in a build where I will follow the 4L80ECC/MSRK instructions exactly. I plan to source a 2004 4L80E 2wd. 1. TCC Regulator mod - Sonnax drop-in TCC Regulator Valve part#34994-01K 2. AFL Valve Bore - Ream the AFL Valve Bore & install a oversized AFL. Sonnax S34741LK if you have the tool, otherwise Trans Go part# 48-ACT-TL. 3. Sonnax Transmission Boost Valve & Sleeve 4L80E-LB1 (is this needed after performing the mods in the 4L80ECC/MSRK instructions? 4. Use a wave plate in the direct drum but ensure that it is from a TH400, and not a 4L80E as the TH400 is stronger. 0.060" 12 lug 5. Drill a hole in the direct drum even if not going with a brake. A .050" ish hole on the outer edge of the piston bore will help release faster on a 3-2 downshift. 6. Use a wave plate in the intermediate clutch in EVERY 4L80E/TH400 build that uses an iron direct drum. This helps with wear on the intermediate sprag. 7. Plug the reverse feed in the center support, as this keeps 3rd/Reverse oil from leaking between the Support & Case. I hear a TV Exhaust checkball from a 700R4 works great. 8. Omit checkball #9 as I'm dual feeding the direct clutch and want to speed up reverse apply (Apply of the direct clutch in reverse). Should I do that or drill the apply orifice to .086-.093" to speed up the apply & leave #9 installed? Some specific questions regarding my parts list below: 1. How critical is the brand of steel plates. 34139EA comes up as a common number for the kit, but the kit includes 5 Direct steels that are .090" and 5 forward steels that are .077", so if you are planning on going all 0.077" in the forward and the direct with the exception of the single cushion, you need to buy 5 more direct steels that are #34128. 2. Should I use Kolene Steels instead? 3. For the wave plate in the direct drum, are we talking a steel cushion plate, waved .060" 12 lug from a TH400 part #34127? 4. Thoughts on using 1 kolene Intermediate steel 0.100" that will be put against the piston #34124K? 5. Since the 4L80ECC/MSRK already comes with a rubber bonded piston for the direct clutch, I won't need 34965G that comes in piston kit 34960A, correct? 6. I read that every 4L80E direct drum has a Bleed Checkball in it, and that some TH400 pistons do not have a bleed as some TH400's used a drum bleed and some used a piston bleed. Since the 4L80ECC/MSRK kit already comes with the direct clutch piston and spring assembly, I should just use that and not need to source anything from a TH400, correct? 7. Do I need to verify correct travel for the reverse band servo and correct pin length? Is there any way to do this without buying the gm tool? I have the tolerances for end play as follows: Total Rear Unit.....003"-.008" (Rollerized) Reaction Carrier to Center Support......008"-.015" Direct Drum to Forward Hub......003"-.008" (Rollerized) Front unit.....005-.008" more/greater than the Rear Unit If I wasn't purchasing the 4L80ECC/MSRK kit, I would perform the following mods but I believe these are already all taken care of when you buy that kit and follow the instructions: - Use the Brass Thrust Washer that came from the Case Thrust between the Reaction & Output Carriers....Replacing the Plastic Thrust Washer (covered in CK instructions) -Remove/omit the second from the top Sealing Ring on the Center Support. (covered in CK instructions) -Omit the "Center Drum" lip seal in the direct drum. (covered in CK instructions) -Plug the "Direct" Reverse Feed in the Case.....I do not like the thought of ramming a set screw into the Center Support, Loctite the set screw in place in a position where it does not interfere with the Support. The industry standard is to use a parking pawl cup plug. (covered in CK instructions) -Enlarge the lube hole in the Overrun Clutch housing with a .125" drill bit (covered in CK instructions) -Replace the Overdrive Sun Gear Bushing with a "Fluted" Sun Gear Shaft Bushing. A bushing kit will only come with 2 sun gear shaft bushings, You will need to purchase a third. (covered in CK instructions) Anything in the parts list below that I should swap out? Any mods that I am missing?