76- 4oo engine Can i get 500-550HP stock exhaust

I did a lot of cam testing with that low deck engine. It ran best with a Mopar Performance .528 solid flat tappet. 550 HP was no problem on the dyno with the exhaust manifolds and pump gas. It wasn't exactly a sleeper because the .528 cam has a bit of lope and I had 3 inch exhaust on the car, but it was pretty darn quiet.

With a hyd flat tappet the engine was much quieter and it only gave up a little bit of power. If I was going to do that engine again I'd probably use a hyd flat tappet or a hyd roller. Just depends on the budget.

There is a trick to making power with the exhaust manifolds. It isn't an expensive trick, but it is important. Guys like Dwayne Porter can solve the equation for you. Or just follow my build using the same exact parts and you'll make the same power.

I wrote a bunch of magazine articles on that motor so do some searching. You should be able to find the cam article as well as some intake testing and the dyno tests.

My big block book is also available on Amazon.com if you're interested. I covered that engine in the book as well as various other builds.