I recently purchased a 408 done by a family friend which I’m no longer in contact with. He left me with some info on what was done but I don’t think it was a properly thought out build. The car seems to be lacking power and no matter what I do and can’t get it to stop pinging under load. I was wondering what I could do without spending a ton of money on bringing the car in.

This is is the info I have on the build
-408 scat flat top stoker kit with forged pistons
-mopar m1 single plane intake
-lunati hydraulic roller cam and lifters(Advertised Duration 270/278, Lift .515/.530)
-j 202 heads ported
-holley 750 carb
-(no idea on compression) shouldn’t be higher than 11.1) I have tried octane booster with no luck

I apologize on my lack of knowledge, figured I’d ask someone with more knowledge on this stuff, thanks

Yes. It starts and idles fine. And even high rpm it’s fine just under load it pings