Payton

They are 1991 454Mags with about 350 hrs. the last 3 with Wieand 177 blowers. Ive got Crane cams I am going to have to check the #. It was slightly larger that the Merc 420 cam. If I swap to aluminum heads What kind or size should I run? Should I go the custom cam route and change over to roller rockers? I've been running Crane gold rockers for 5 years. With aluminum heads could I get by running 89 octane? That is what's available in my marina.

Thanks for any replies
Mark

MILD THUNDER

iTrader: (3)

Hey Mark. The big feat is gonna be 89 octane with those blowers. Have you considered selling the blowers, and turning your engines into 496ci strokers, with a good pair of Dart or AFR aluminum heads, converting to a hyd roller cam, basically some nice N/A mills that will run on 89, and still make decent power. Or possibly selling your engines complete, and building some N/A 540's based off a 502 block.

Payton

Joe, I was wondering about that. I really don't need more power, ok maybe a little more. Some 550hp 540s would be pretty mild and run on 89 wouldn't they.

MILD THUNDER

iTrader: (3)

For sure Mark. With the right heads, cam, and compression, I think you'd be pleasantly surprised. 575-600HP is not out of reality. .

A long time ago I had a 540, 9:1 with iron merlin heads, and a crane 741 roller cam, single plane dart intake, and 1050 dominator. It made 585HP and 615ft lbs. Nowadays, I would have done it a little different. I'd get some aluminum heads right from Jimmy Valako up in Holland. And theres some really cool EFI stuff out nowadays too. Mikey Sommers turned his 502's into 540's a couple years ago. Using the GM rect port heads, mild setups, they made 575hp. I'd recommend some aftermarket aluminums though for sure.