I am thinking about doing some engine / exhaust upgrades. I dont want to drop a bunch of money at once so my first thought is to update my intake with edelbrock rpm air gap. Currently I have a q-jet performer intake. Along with the intake ill need a new carb and thinking about either a demon or holley 800cfm

Long term I will get rid of the stock exhaust, cam upgrade, maybe pistons if needed(not sure whats in there) roller rockers , valves pushrods and maybe heads.

Will i see any difference with just the intake/carb change?

Where would you guys put your money first?

Is it a 454cid engine----Merc 330hp? or what model?

drpete3: "Will i see any difference with just the intake/carb change?"

No, most likely not. I would start with a better breathing aftermarket exhaust system first...such as a Stainless Marine or Dana, GIL or something comparable---they're not all equal in performance or durability so choose wisely. Without a better breathing exhaust system the induction stuff such as cam, intakes, head mods, etc are not going to help much at all until you help the engine breath on the exhaust side---it's just a known fact and is critical.

At the same time, just adding a set of aftermarket exhausts are not going to help much either as far as top end speed, but it will give you a kick in the midrange and should help in the cruising range speeds. However, once you have the better breathing exhaust, then as you add intakes, carbs, cams, head mods, etc, etc then your engine/boat will/should respond with each upgrade addition. An aftermarket exhaust system will also add some BLING effect to your engine compartment and a better sound that you will like.

Others will weigh in on other options you may consider. Have fun.

By the way, where do you do most of your boating? Torch Lake, GT Bay, Cheboygan/Indian River???

I am unsure what engine I have in the boat because its not stock. Its says TCM on the valve covers and i am pretty sure it came from TX. I dont know what pistons I have in it. Or if its been bored out(rebuild). Nothing.

This is what I was wondering, re: exhaust. Ive been watching ebay and others sites too.

Mostly I am on a smaller lake called Lake margrethe in Grayling. I was just up on Burt Lake this past weekend though. Lots of fun.

How about you? Lake MI?

I ran a performer oval port on my 454 then switched it to a performer rpm and noticed absolutely no difference, except the hose from the circluator pump was a little too short