The 2399 number should be a domed piston. The last 2 numbers after those should be the over bore. 10 is .010 over and so on.

I have budgeted for new heads so if top of the line aluminum heads offer an improvement I'll start shopping themIf not wanting aluminum heads or better heads thats why to stay with these 781 castings . 049 & 781 best 2 large oval port cast iron heads gm used .
Agree but I really want to keep it mechanical fuel pumpTruth be told, if I had this gift horse, I’d probably make sure it had a roller cam, and buy a good injection system instead of the heads. You won’t regret it
If money was no option, roller cam, EFI, and Heads...
I am not doubting the benefits and if I wanted to make this a 700 horsepower engine I would probably have to go that route. I'm just stubbornly steadfast I'm keeping it mechanical.Meh, the fuel injection benefits are worth it
Agreed. I get the idea of keeping it simple but then I start mine with one twist of the key in below freezing temps and know a carb wouldn't do that. Nor does one start as clean when hot with a carb. No transition issues with an accelerator pump leaking or issues from our wonderful ethanol laden fuel clogging up passages in a carb if it sits for any length of time.Meh, the fuel injection benefits are worth it
It’s more about driveability and maintenance like Zoo said. I switched in 2006. It’s a benefitI am not doubting the benefits and if I wanted to make this a 700 horsepower engine I would probably have to go that route. I'm just stubbornly steadfast I'm keeping it mechanical.


What other equipment is required for that EFI setup? Wouldn't it also require a different intake manifold? Is the tuning done by laptop?Come drive my K5 454 w/Edelbrock Pro-Flo MPFI = throttle response is fawken amazing! I can Rap Rap Rap the engine to jingle bells tune if I want = zero delay
Oh and dibs on the 781's if you go aluminum![]()

Honestly I think the pro-flo setup is the one I would use if I was converting another one. I'm running the oem system on my 8.1 as there isn't much in the way of the pro-flo for it. But for a regular big block the pro flow is the way to go. No laptop required. Self learning.There is a Pro-Flo 4 thread in the injection forum here.. those guys know way more about the new stuff than me.. = old school![]()