I decided to start a new thread once I had the complete facts. I had stated in another thread about rebuilding the pump on my 94 GTX and noticing a loss in power. I naturally assumed it was due to the impeller I purchased from SBT. A refurb. They sent me an impeller with a different part number than stock and told me it had been re pitched to the stock pitch angles and it would work just fine. So I got ahold of some pitch templates and tweaked the trailing edges to get them closer to stock but it still wasn't 100%. So I decided to purchase a good used impeller. I removed the SBT refurb and compared to the stock one and saw the difference. The stock 94 GTX impeller part number ends in 280. The one SBT sent me is a 400 off a right drive on a 94-95 Speedster. Although the leading and trailing pitch angles are correct the difference is in the length of the vanes or the distance the vanes go around the impeller. The 280 has a leading edge that starts sooner or thus ends up having a longer vane. Pics below show what I mean. Moral of the story is I could've re pitched this thing till the cows come home and it wouldn't be right. SBT is selling garbage and doing shoddy work. This is more proof of it. They're customer service and a technician argued with me over it and they're wrong. Do not trust these people they should not be in business.
280 stock on left 400 on right.
280
400

280 stock on left 400 on right.

280

400