4l80e questions

TType85

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May 25, 2001
Questions for those who converted over to a 4l80e. This is not a "don't do it stick with a 200r4 post". I am exploring options since I need a transmission no matter what. This car has been through no fewer than 5 transmissions since the late 90's due to bad builders. The current one probably broke the input shaft or a drum; haven't pulled it out yet.

The car has a Holley Dominator so I have a controller for the 4l80e, the car will be around 600-650hp.

So far it looks like for the conversion I need:
  • Transmission
  • Converter
  • Wiring Harness to Holley
  • Adapter Plate
  • Modify/Replace transmission crossmember
  • Modify transmission cooler lines
  • New driveshaft

Questions:
  • Do any of the aftermarket crossmembers work with a pypes dual exhaust setup for those of us with no welder?
  • Does the stock shifter cable/linkage work?
  • What about the neutral safety / reverse lights?
  • Is the yoke on the TR driveshaft the same as the one for the 4l80e?
  • Do you need to "trim the ears" on the transmission to fit?
  • Do you need to flatten the body seam?
  • Can you run a lockup converter or is it better to go non-lock (would like something equivalent to the PTC 17 blade I have).
 
I would flatted the body seem just to save knuckles and backs of hands.
Yoke is different. 27 spline for the 2004r and 32 spline for the 400/4l80e
You say the 2004r was a victim of bad builders, so even though this isn't a keep the 2004r, I would encourage revisiting it with a competent builder as 650 can be done reliably. Adding in a whole new variable with different ratios, adapter, driveshaft, et all ain't cheap.
The problem with the 4l80e is the weight, converter selection, and all the mods needed to get it installed.
Good luck on that journey if you embark, and I would love to see pix as you progress.
 
Is your choice also based on keeping OD and not having to shift manually?
Yes, I would like to keep OD and automatic shift unless it was an actual manual (which I know is not a great option on TR's)
 
You say the 2004r was a victim of bad builders, so even though this isn't a keep the 2004r, I would encourage revisiting it with a competent builder as 650 can be done reliably. Adding in a whole new variable with different ratios, adapter, driveshaft, et all ain't cheap.
I am exploring all options. I know I will have over 4K in to a full billet 200r4. The failures before the current one were from stuff like smoked clutches and bands with the trans setup and installed by the builder (we didn't touch the TV adjustment after it was set by the builder). This time the failure appears to be a snapped input shaft or something similar; this trans was holding up ok till this week.
 
Yes, I would like to keep OD and automatic shift unless it was an actual manual (which I know is not a great option on TR's)
Understandable. I won't be driving my car on the highway much so loss of OD wasn't too much of a factor. I will say that I do enjoy the RMVB and shifting manually with the TH400. Took a little getting used to but didn't take much time for it to become 2nd nature. Good luck with your decision / build.
 
Driveshaft will need shortened, yoke is the same as a TH400. The shifter linkage will have to be modified to work, when hooked up, that takes care of the neutral safety switch and reverse lights. PTC can get you a good non lock up converter. 4l80s dont have a mechanical speedometer on the tailshaft. There is a company that makes one though.
 
My money would be on a snapped shaft on the fwd drum if it wasn't a billet shaft. Trust me when I say, I've had 2004r trans in and out of mine way more than I'd care to admit. Mine had a 700r4 for a long time, but I decided to learn and assembled a 2004r and that seemed to go well for me.
I have no prob seeing why a 4l80e would be a good idea. I just think for 6-900 hp a 2004r is a viable option. Im not even sure it needs to be a fully billet unit that might cost $4k. I would give David Husek a call and talk over what you are doing and what your goals and expectations are. I'm confident he or one of the other builders can put together a unit that would get you there.
 
My money would be on a snapped shaft on the fwd drum if it wasn't a billet shaft. Trust me when I say, I've had 2004r trans in and out of mine way more than I'd care to admit. Mine had a 700r4 for a long time, but I decided to learn and assembled a 2004r and that seemed to go well for me.
I have no prob seeing why a 4l80e would be a good idea. I just think for 6-900 hp a 2004r is a viable option. Im not even sure it needs to be a fully billet unit that might cost $4k. I would give David Husek a call and talk over what you are doing and what your goals and expectations are. I'm confident he or one of the other builders can put together a unit that would get you there.
I located a 2004r that has the billet drum shaft and other normal upgrades for 650hp local to me that was built buy one of the guys I know can build them right. I am going to give it a try; If I end up breaking this one a 4l80e will be going in. This car has been bad luck for transmissions even before I owned it.

Looking at the log it looks like it snapped right at or after a 1-2 shift; I was in slow traffic lane (25-35mph) and got on it moving to the other lane. The trans that was in the car did not have any billet upgrade parts.

I was already backing off the throttle due to tire spin as boost was coming up to about 25psi. The 6766 takes about 1.5 seconds to go from 0 psi to 25+. The shift was at 5800 RPM then it broke and shot up to the rev limiter. Maybe when the tires hooked up is when it broke? They are 275-35/18 Nitto street tires, not drag radials, so they are not very sticky. I recently swapped from a torque converter that has way too much slip to a PTC 17 blade which probably contributed to the death.

This was about 1.5-2 seconds total in the log. dark red is RPM, bright red is boost, purple is GPS MPH and green is TPS.
1668392189323.png
 
Ive had full billet 200s from dave husek take hits with the turbos coming in .3 to 40+psi.
I would call dave
 
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