Another winter is here, which means its time to tear down my car for another seasonal build. I was having an issue which required me to drop my transmission, and when draining the fluid it was littered with brass... Which means to me that my 10 year old transmission at least needs to be looked at. As you all know transmission parts are getting harder and harder to find. Currently my car sits at 563wph/422ftlbs on pump gas. Someday I would like to go flex on e85, which is now available by me. So the big question is where do I go from here? My transmission is a TRE "stage 2.5" (not offered anymore) with an EVO3 1st year and 4 spider. I am thinking my options are as follows, but please chime in with any helpful advice if possible. and NO, I WILL NOT GO AUTO!!! (glad to clear that one up...)

1. Send my trans back to TRE to have it inspected and freshened up, run it until it pops.
2. Send trans back to TRE to have it inspected and add magnus 1/2 fork, billet bearing housing and 300m output shaft as upgrades
3. Go dogbox...

The car is mildly used on the street and drag strip. I say mildly because I rarely drive the car and only take it out to have fun with, not to just cruise around town.

With wanting to go E85 & higher power I think biting the bullet & going dogbox now would cost less overall in the long run.

Or auto swap if you can stand the idea...

I vote to refresh and upgrade what you have. That’s exactly what I’m currently doing with my 13 y/o tre trans with a evo3 gearset/4 spider also. Should have got in on boostins Black Friday deal. Just picked up a bearing plate for $700

When I started my dogbox build, Tim Zimmer told me he would need an unbroken core to start from. That was over 2 years ago already. So I think if it is pretty easy for you to get another unbroken core besides the one you already have, you could risk the one you have by just refreshing it and just see how long it lasts.
For me it wasn't easy to get an unbroken core (1g). Mine was broken and I wasted a lot of money on crap trying to come up with an unbroken one. Maybe that situation is better with a 1999.
Then after getting the dogbox in the car I gradually realized that wasn't the end of it. I think some kind of lockout shifter is pretty much almost required if you want to race it. Or a sequential shifter like the Ikeya, if you could ever get one (not made anymore as far as I know). It also seemed to me that changing from a heavy single disk clutch to a lighter twin disk made some things better, and that is something I wasn't planning on.
My "build" thread is almost entirely about this. Mine has been in the car for exactly 2 years now. Since Jan 7, 2020.

were on boost - Thank you for the info, i will check out your thread. I do have a spare trans in my garage out of a 98 (ive collected parts over the 15 years or so ive had this car) so that isnt a huge ordeal.

My best friend has a 97 16g car. My trans once cleaned up would be perfect for his car if i choose to do a dogbox, however how bad is it on the street? honestly I do take the car out and it is not a 100% track car im afraid a dogbox will be unstreetable due to rumors only. I have zero experience with them, so your feedback would be great. Thanks

Well I don't think the dogbox is unstreetable. I do drive mine on the street, no racing. Just a fun drive maybe once a week if the car is not apart for something. I would just say that I was expecting it to be not as bad as it is. I mean stock motorcycles pretty much all use dogboxes right? And they shift so nice. And when you watch videos of cars with a dogbox, you usually hear just a little clunk. That's if it's a good video with good sound. If it's a crappy video you might not hear anything at all.
I find with mine that the violence of the dogs engaging is extremely variable. It can be anything from silent, to a mild clunk, to a loud clunk with a heavy thud that you feel through the whole car, to a grrrrrrrrrrrrrrrrr - inding agony that happens when the dogs don't fall right in to the first pocket they come to.
So the agony for me is not knowing how long it will go like this before things get worn to the point where I start to notice problems, like jumping out of gear or whatever these things do when they get too worn. So far I haven't noticed any deterioration in how the trans works. But I only have 469 miles on it!