I have the savage 25..

Is it a tunine issue, or a worn engine.. or possibly a half tank lean

When i first start the truck cold, its WONDERFUL.. runs great, for abotu half a tank...

After that half tank... it runs fine at high speeds... but it wont run very well after a high speed run then slowing down and hitting hte gas again... it is really rough running on the low end, i richen it up any everything, but no luck....

Could it be a worn engine, or a half tank lean..

BTW, temps are abot 230F

you might just have the half tank lean

sup nick.. i think that was oyur name..

Well, with hte header tank mod. . you just take a tank, and mount it lets say, on the roll bar.. then attach them into each other?.. what about the exaust lines.. i would have 2 exaust lines and only one exaust?

just do a mid tank or get the new era tank.

and yeah it's Nick...lol

is a mid tank the same as a header tank?

not really

the easiest way to go is t just get a new era tank

Well, i have a extra tank here thats kinda why i want to do the header mod...

But what do i do with the exaust lines?

i took the RC10GT Tank i had in my evader out and mounted it like this \ in the roll bar.. it stayed full while the main tank got low.. but my hump pack died so i couldnt try it more...

Sounds like you hooked it up right then. The pressure line from exhaust goes to the main tank, then the outlet on the main tank goes to the inlet on the header tank, then the outlet of the header tank goes to the carb...you will not get two exhaust lines setting it up in series like that.
Refill the main tank when it empties, dont let the header tank drain. Well with your setup you can but a lot of guys run airplane fuel tanks as the header and they are a pain to fill and the purpose of the header tank mod is to supply fuel from a vessel that is constant, that way it will work at its best.

well, i can easily still fill the header.. i can still access the lid..

And it seemed to work well... although i couldnt even get to half tank lol.. it stayed filled.. and yes, that is exactly how i set mine up.. at first i had it backwards, and realized that wouldnt work bc hte header would just run out of fuel and be purposless lol..

The easiest way is to do the uniflow mod. A 2" piece of fuel line and a way to connect it to the inside of your tank cap. If you are interested I'll explain in more details with photos.