So I have a bone stock 225 slant six automatic dart . I want to beef up my car any tips for the engine or tranny I wanted to know if I switch to a manual would It be a lil faster or a lot and what transmission would fit and is the best would it actualy be better for street rod and a lil racing here and there or stay automatic 3 gear help:( plzz tnks for any advice

The change of the transmission won't make it quicker or more powerful.

Depending on the style of driving and the type of manual transmission it might give you a mile or two back on your overall mpg at best. Also if drag racing, unless you are super shifter, it won't help you be 'consistent'.

If set on going to a manual transmission you are looking for a 3 or 4 speed transmission out of a 1967-1976 A-body (and bellhousing and transmission out of a 1976-1980 F-body) as your bolt in choices. You will need all the donor parts from a 1967-1976 A-body. You might also review the article on 4 speeds on the board article section.

-D.Idiot

What would u do leave it a 3 speed automatic or change it and to what?:)

I would leave it as is...unless you have a plan in mind, the A904 automatic is fine for getting around, and can be rebuilt to take abuse if quality parts are installed.

-D.Idiot