I just put my new cobra exhaust on my 300ex...do i need to have my carb jetted...??

 

yep

 

What if i dont get it jetted?

 

Do you have any drivability problems? Bogging, missfire, smoking exhaust,back fireing, or hard starting?
Hows the spark plug look? wet, oily, dry,black, white?

 

OK, i put my new cobra exhaust on...the only smoking i had was the paint coming off the head pipe, which is ordinary right? its not heat paint that was on there...but i only noticed backfiring when the exhaust wasnt completely mounted on the engine block...uhm...Dont know about the spark plug but last time i checked everything is fine...
well...?

tbuck

 

is there alot smoke coming out of the exhaust? does it like bog down at all? and does it still back fire, im asumming u fixed that problem right?

 

NOOO...theres no smoke coming OUT of the exhaust, its just paint coming off the exhaust, its melting because its not heat paint, and it doesnt backfire anymore, but i gunned it today in second and it popped maybe once, but not loud at all, hardly noticeable

TbUcK

 

The smoking is normal, itll eventually go away.
Hows it work when you hold it wide open? Missing? breakup? lazy? After you get a feel for how it pulls @ wide open, tape the intake partially closed with duct tape, maybe cover about 1/3 of the opening. Then take it for another test ride, and if it runs better, then the main jet should be bigger. Covering the inlet with tape, will make the motor run richer.
If its starting fine, the pilot circuit is doing good. If you get more backfireing...then go a bit richer on the mixture screw.
Keep an eye on the spark plug, you dont want to run lean.