XM262H with Stock 5.7L?
 

Im just looking to do a minor performance upgrade to my boat. I did the 4 barrel conversion and put on an Edelbrock Performer with Edelbrock 1409 carb. Im wondering if I can get away with keeping the stock heads and putting in an XM262H cam without messing with the heads and exhaust system.

Just looking to get this thing to 275HP-300HP without spending the money on heads if at all possible.

If Im dreaming..dont be afraid to tell me so.

-Geoff

I think you will loose too much compression pressure if you have 76 cc heads.
Mid-range performance will suffer.

A pair of 64 cc Vortec heads will do the opposite, i.e. give you a nice midrange and a bump in peak hp's.

Geoff,
You will have to change valve springs for sure. The Comp 981's may or may not be a direct drop in depending on the configuration of your factory heads in regards to rotators and stock spring heights.

I personally think you will see a lot more gain by upgrading the exhaust.

Bill Koustenis
Advanced Automotive Machine
Waldorf Md