y make a dummy i have a trakpower pack
whats the problem if you have to mod a car slightly? its "model" car racing most have modeling skills and companies already make lipo fit kits for cars
ill state again the 30mm trakpower will fit in the b4 by just rasing the bat strap posts, i have posted pics on this forum (look in associated thread)
they WILL also fit in a b44 by just lifting the batt straps, and the same for the d4 id you space the rear top deck 2mm up.
i have already suggested you get all the dimensions for lipo saddle off the manufactures site and go with that.
there is no point in making a rule that outlaws what is already available!
b4
http://www.oople.com/forums/showpost...9&postcount=31
b44
http://www.oople.com/forums/showthread.php?t=10160