hmmm im not 100% sure about this yet they can both be made to reach the same speeds just i thin 1/8th's r usually stock, faster cause their engines are like up to .28's i think like i have no idea really about 1/8th cars yet ithink this is the case. so generally 1/8ths stock are faster yet i think with mods that the 1/10th's will get faster cause theyre alot lighter, if anyone knows what iv said is wrong please correct me im just going off what i think i was told.