Modifications Help

Ok, i am about to start seriously moding my car... and some of the things i need to take care of is the Speed Limiter... and would any of these products work? (car= 1992 Pontiac Grand Am SE V6 3.3L)
http://www.sportcompactonly.com/par...&pl=713&p=78190
en i was looking at this product:
http://www.sportcompactonly.com/par...&pl=703&p=74227 (http://www.sportcompactonly.com/part.aspx?c=30&pl=703&p=74227)
i mean i did find these products with my car info entered for the search...

and also, i been looking at throttle bodys, and i noticed the ones taht are 62mm, and then i found one that is 70mm, would that cause any problems for my car, like when i need to go back and get it checked, like any emmisions problems? or noise problems?

http://www.sportcompactonly.com/part.aspx?c=2&pl=2252&p=84075

and does any one know where i can buy some Headers for my car? or would i have to get them custom made?

also, does any one know where i can get other mods for my car, like upgrade cam shafts, pistons, etc.?

thanks for all the help!

No need to post twice on the same topic Djpac. :nono:

Check your other post, this is closed.