Never over 225 and when it hit that was shut down... added fans and now never over 200. Timing at 20. Edelbrock heads. AF unknown. No smoking..... Runs smooth. Just not a screamer.
The scoop. I did buy the 545 engine and talking with others was convinced the cam might be too much for street use and would have little or no vacuum. Talked to ATK and they agreed. ATK advised the only difference in the two engines was the cam. The 545 version has a Comp cam 253 253 with 585 585 lift... the 515 engine has a Howards cam 225/225 and 536/541 lift..........I made the cam swap. Now running the Howards cam.My personal experience with ATK is that they almost always fall well short of their advertised HP/TQ numbers. I've helped two guys put their 347 "410 HP" engines in their cars, one a 4 speed Falcon and the other a Fairlane. Both were disappointing to say the least even after a few months of tuning on them, and when we dyno'd the Falcon we found out why: it put out a touch over 220 HP at the wheels through the manual trans....your 502, if it's the "515 HP" only has a hydraulic flat tappet with 225/235 @050 .536in/.541ex on a 112LSA. Pretty small, and along with that carb, and depending on your headers and intake, isn't going to be a real ripper on the top, but it'd be great in a F100 or the like. The base of the engine is good, just needs some stuff changed out in the way of a custom cam/intake/carb swap, and a good set of 1 7/8"-2" primary headers.
Not a lot of room for larger fan. Bottom of the shroud fan almost touches. Im very disappointed in the ATK engine. Its not making anywhere near to 515 HP.+1, get your total timing right. You can mess with the less-important idle timing after.
Sounds like you have some tuning to do. Whatever it will give, it won't do it until everything is tuned.
You solved your cooling, but your flex fan is too small for the shroud. A 7-blade paddle-blade fan of proper size will pull much more. Use it with a clutch (with coil spring on the face) if you have room.
My engine was complete and dyno tested. Let me know how much power it makes.I bought the same engine for my LTD. Still not installed yet, but I bought the fully dressed version, so it came dyno tested. The Dyno sheet was packed with the engine.
ATK recommends 30 to 34 initial timing.Whoa! Initial (base idle) timing is 30°? That's dangerous, as it will add unknown timing as it revs.
As you do not know the centrifugal advance in your distributor, you can set timing by total (all-in) advance at high-rpm. Disconnect and plug the carb-side of your vacuum advance (if you have it). While watching the timing with the timing light, rev the engine until the timing advance stops adding timing. Note the degrees. Adjust the distributor position until the total timing (all-in) when revving to all-in is 34°.
If it were me, I would confirm exact timing mark location with a $10 spark plug thread timing stop (or make your own). Then if you do not have a dial-back timing light; add measured marks every 5° to 40°, before setting timing as-above. 34° is only a place to begin timing tuning, but should be much closer than guessing, and certainly safer than what it is.