Alright, Im a newbie to all this so sorry for asking stupid questions in advance. I recently picked up my first boat about a month ago! (have only owned stand-up jet ski’s, sea-doo’s, & a wave runner (follow me on insta: @classic_jetskis)). It is a 1975 Spectra 19' w/ a "freshly rebuilt" 455 olds engine with jacuzzi wj pump & American Turbine energizer kit. Picked it up from a lady selling it for her husband so I do not have all the information or history I was hoping to have when buying it. Took it out for its maiden voyage after some minor maintenance, ran strong up until I reached around 35mph (forgot to look at the RPMs...rookie move) when I believe the secondary flaps open it then bogged down and sounded like it was backfiring until I let off. Did this a few more times to see if there was a barrier I had to get over to get into the higher RPMs until it ramped down and died.
Where I am struggling:
The Engine: 1975 455 Olds? I was told this but after having engine issues and doing some more research I am not 100% sure on what model & year it is. It has an engine block code of A with a number 383821 and is painted a light blue. When looking this up it comes back as a 1965 400 or 425. Other than that all I've found out is compression is ~140 psi and it had ACDelco R46SZ spark plugs (equivalent plugs:
http://www.sparkplug-crossreference.com/convert/AC_DELCO/R46SZ). If you have a way to find out that I have not tried or if there are more obvious signs please let me know.
The Carb: 800cfm Edelbrock? Based on what the seller told me, the color of connections, and look I believe it is a thunder series 800cfm with a manual choke. Unfortunately the serial/part number is not located on the outside of the front mounting flange like where it should be. Other than that I do not know what jets or tuning springs it has, just reset the secondary flap spring tension back to factory settings. If there is a way to measure the size of card or visual signs, again please let me know.
If anyone could help to identify, any thoughts on how to get into the higher RPMs and/or just general engine advice it would be much appreciated! I am already considering getting a 650 or 750 edelbrock since everywhere I look says the 800s are more trouble than good. I am just wanting a reliable (
lol ) engine/carb setup to start with before I do any major mods. Thanks for the help!
