From those that have done it. In a street strip car. Would you run a Th400 or 4l60e. I’m planning 500+whp.

 

If you had said street only, I'd say 4l60e.
Strip only, TH400
But since you said both, 4l80e

Those would be my choices if I were forced and automatic. I really prefer an overdrive on the street but a 4l60e tend to be a weak link on the track. 4l80e not so much a problem handling abuse.

To each their own, good luck.

 

Isn’t the 80 a nightmare to install

 

I've checked a few swaps on the boards. I'm not saying it's a drop straight in thing but neither is dropping in a th400 that the car wasn't designed around. Quite a few years ago Pocket fabbed one in. Post #467 or so https://www.thirdgen.org/forums/ltx-...t-left-10.html

also https://www.thirdgen.org/forums/tran...l80e-swap.html

I mean you want a street strip 500hp. If you can live without an overdrive then you could compromise to a th400. If you can't then you may want to compromise 500hp or the strip part. 4l80e is more work but you will likely have the most happiness with it done. Hopefully you'll find what works best for you.