I purchased a 455 out of a 70 riviera with 23k original miles on it. Rebuilt the entire motor. Doesn't seem to have any more power than the 350 that was in my 71 skylark when I bought it. I was at a car show last month and a buick guy told me he set his timing on his to 14 degrees btdc. Instead of factory setting. Does that sound right to anyone? I believe it may be because my rochester 4bbl may be messed up. Any thoughts?
Not safe for your engine. 10 degrees timing is added all the way up the scale. At cruise, at full throttle, up a mountain, etc. Can cause serious engine damage. Start with carb maintenance and adjust. Check for vacuum leaks, busted diagrams, etc But stay by the book on timing until you get advice on distributor and timing modifications.
I didn't think that sounded right that's why I asked before doing that. I figured I would ask people that do this, not someone who is having a car built for him.
Total timing and how fast it comes in is what's important. You need to find out what distributor you have installed and how much mechanical advance it has built into it. Another point- make sure your throttle cable is opening the carb all the way. With the engine off, hsve someone mat the gas pedal while you look down the carb. The secondary throttle blades should be vertical. I cant tell you how many times I found that a carb was only opening 75% of the way. One quick adjustment was like adding 50hp!
Exactly which TA distributor did you buy? The Big Cap GM HEI style with coil in cap, OR, the Ready to Run small cap distributor. Which part number? Your answer will dictate what your initial timing should be.
I would have to follow them back. Can't remember how i ran it when I hooked it up. I believe I ran the wire from 12 volt key on supply but it has been a while so I will have to trace it back. I believe the original points wiring is gone.
It has the big cap because my GS air cleaner hits the top of it. Even with a 3/4 inch spacer under the carb.
OK, that distributor needs full time battery voltage. Simply hook up a meter between the engine harness power wire, and ground. With the key in run, it should be 12 volts. That distributor has 22* of mechanical advance. That means if you want 34* of WOT advance, you run 12* initial advance. When you set the initial advance do it with the engine idling as low (less than 1000 RPM) as possible. That will ensure there is no mechanical advance in. It wouldn't hurt to check the total advance as well after you set it up.
Thanks to all, seems like it was a combo of timing and some carburetor issues. Seems alot better now. Carb 4bbl lockout was sticking and not letting the 4bbl kick in.
