I have a 1970 Buick Electra with the original 455 - stock...needing some recommendations. Here’s the deal...from a dead stop, I can floor it and it’s sluggish off the line. Sounds as though its bogged down. Weird thing is, it'll peel off, but after that, it fights to get up to speed. Not the power I know these cars are capable of. I’m no expert on engine specs, but I believe the 70 Electras were rated at 360-370hp stock. Here’s what I know/have tried: 1. Advanced the timing 2. Plugs and Wires 3. Replaced the coil in distributer (HEI) 4. Rebuilt Carburetor Note: I've only run non-ethanol gas through the tank since purchasing in August 5. Recurved the distributor The things mentioned above helped a little...but there is still much to be desired. I plan to do a compression test next to see if I getting weak compression from one of the cylinders. Also, there is an exhaust manifold leak. I've also considered the torque converter. Is there any way to confirm or eliminate if its the TC? known issues/history: Other than the sluggish take of, there are no other issues that I've noticed listening to it run at idle or in park. No knocking or tapping. However, there is an exhaust manifold leak on the driver's side. The engine was rebuilt sometime in the late 70s. In the owner's manual, there are notes explaining that when the engine was rebuilt, a 70-76 camshaft was installed in lieu of a 70-71 camshaft. I’m thinking that could very well be the issue. See the lift specs below. 1970 Exh. Lift .458 Exh. Duration 332° Cam Spacing 117° Timing Advance * 124° 1976 Exh. Lift: .405 Exh. Duration: 306° Cam Spacing: 113° Timing Advance: 113° If I have to go any further and dive into the engine...my budget says...put the stock cam back in, get new manifolds/gaskets, dual exhaust and stage 1 heads from TA Performace. However, a couple of local shops say it'll be cheaper to put an LS in it and call it a day. I'm not trying to make it a drag car and that's way over ny budget. Just trying to get decent HP. Between 360-400. Sorry for the dissertation. Any suggestions/recommendations?