Do I need new injectors?

i could be wrong but with that combod i would assume you would need 24lb injectors...........

24s

You need to upgrade to 24# injectors

Don't be too quick to go to 24 lb injectors. At 38 PSI, the 19 lb injectors are good for 300-320 flywheel HP.

With non ported GT40P iron heads, I doubt that you are making more than 300 flywheel HP.

Play with the fuel pressure and you can tell if larger injectors would be helpful.
At 62 PSI, 19 LB injectors will flow 24.2 lbs.

Get one of your buddies to ride along with you. Find a level stretch of road where you can do some testing. Don't choose a speed range that will make you shift gears, the shift quality & speed will affect your results. Use 2nd or 3rd gear and do a run from 2000 RPM to 5800 RPM. Call out the RPM as it increases and have you buddy record it and the elapsed time. If you have one of those cheap digital watches like I do, a stop watch is built in. Start the fuel pressure at 36 PSI, vacuum off and make a run. Turn it up to 37 and make another. Be sure to reconnect the vacuum every time you set the pressure. Keep turning up the pressure and making runs until you notice a drop off in time. If your bud was careful to record the results, you'll have a nice chart to use to find the optimum pressure.

i will with 30's for future mods