so i was wondering, i have a 78 camaro with a 400 sbc i put a bigger cam and changed the rear end and put one out of an 80 z28 with 3.42 gears. before i changed the rear end the car ran just fine. now it just wants to die. it will run if i keep my foot on the gas, but dies as soon as i let off. also while driving down the road all my gears seem like they are wound up! could the reason be, cause i need the stall converter??  

What cam do you have. If it is winding up more than before it is most likely the gears are now lower.  

here are the specs on my cam

Brand: Summit
Product Line: Summit Cam and Lifter Kits
Part Type: Camshaft and Lifter Kits
Part Number: SUM-K1106
Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 3,000-6,200
Intake Duration at 050 inch Lift: 234
Exhaust Duration at 050 inch Lift: 234
Duration at 050 inch Lift: 234 int./234 exh.
Advertised Intake Duration: 292
Advertised Exhaust Duration: 292
Advertised Duration: 292 int./292 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.488 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.488 in.
Valve Lift with Factory Rocker Arm Ratio: 0.488 int./0.488 exh. lift
Lobe Separation (degrees): 114
Intake Valve Lash: 0.000 in.
Exhaust Valve Lash: 0.000 in.
Computer Controlled Compatible: No
Lifters Included: Yes
Lifter Style: Hydraulic flat tappet  

That cam requires a 2500+ stall converter.  

i know it requires a 2500+ stall, and i was driving it around for awhile with the stock converter til i could get the stall, would that damage my tranny or do i just need to get the stall and then my engine will idle without dying?  

Just as a note, I used to have a Summit cam that was just 10 degrees and .022" bigger on the exhaust and I had it in a 69 Chevelle with a .030 over 327, a TH350 and a stock converter and it ran fine. The cam does have a wide 114 degree lobe seperation angle after all. I now have a 79 z28 with a 355 motor, 4.11 gears, and a 3000 rpm converter and I run about 3200 rpm at around 60mph. That is just the way it is when you have lower gears. As far as the stalling, maybe you have a big vacuum leak or your idle needs to be set up or your timing is too retarded. How high do you have to keep the rpm for it to stay running?