I rebuilt a generic 2004R core for my '84 GN. Basically a stock engine with a healthy camshaft. I'm using a D5 converter and a TransGo VB kit, and the '84 turbo intermediate servo setup. I'm not really satisfied with the shifts. 1-2 shift isn't bad, 2-3 stinks, and it's in 4th way too early. I am using the stock '84 GN governor BTW. Downshifts are extremely unresponsive and late. 3-4 seconds of WOT, and it finally kicks down. Is there any way to tune this valve body to be like a normal turbo Buick trans? Maybe pull the accumulator springs and play with them? If anyone has a BRF, or even the earlier turbo Buick VB, I'd be interested in a purchase from you. I do have a stock '84 GN valve body that has been disassembled if that helps.