i just put a 355 in my iroc;carb, from a 305 tpi the guy that put it in took out the vacuum canister.i had a gm dealer put in the lockup kit for the 700r4 when i left the shop i went to 80 before it shifted to o.d when i got home i adjusted the cable and it shifted around 55 but the slitest bit on the gas and it goes in and out.i have a xe 268 that is suppose to have good vacuum.do i need a vacuum canister for my overdrive to work right or did i get screwed by another clown

 

You have changed this from an injection to carb? The TV cable geometry relationship has changed most likely to have caused the 3-4 shift to be late. This will have to be addressed "first". The torque converter clutch lockup kit, is it operated by vacuum?