performance upgrade for mercruiser 4.3L

[whitedesigns]

Are there any relatively simple performance upgrades a shadetree mechanic can do with a 6cyl 4.3 mercruiser engine? My boat is an Ebbtide Campione 188, 2000 model. I have a stainless prop.<br /><br />Thanks!

 

[Bondo]

Re: performance upgrade for mercruiser 4.3L

If it's got a 2bbl. carb., Put a 4bbl. carb. on it...............<br /><br />Other than that,.. You've got to go Deep, to find more HorsePower........

 

[bluewater19]

Re: performance upgrade for mercruiser 4.3L

Roller rockers 1.6/1 ratio will give you a little more lift and camshaft duration. Dennis moore makes high performance manifolds and risers for that motor also.<br />Edelbrock 600cfm marine carb with the 4.3 tuning kit. Edelbrock Vortec 4.3L 4bbl intake manifold.<br />Assuming you have a 190 hp model now these changes will be good for 30-40 horses or so.<br />These are all modifacations that any backyard bob or shadetree ted can make in a weekend with hand tools and a cooler of beer!<br />Good luck

 

[John_S]

Re: performance upgrade for mercruiser 4.3L

As Bondo and Bluewater said, go to 4brl. Also look into torque shift prop and smart tabs. Plenty of info can be found doing a search on this site.

 

[Bondo]

Re: performance upgrade for mercruiser 4.3L

Also look into torque shift prop

Of the, What Seems like Million$ of Dollar$, I've spent on My boat,.........<br /><br />The Torque-Shift Prop was the Best Money Spent.........<br />

Roller rockers 1.6/1 ratio will give you a little more lift and camshaft duration.

I'd be a little leary of this,.....<br />It Could open the door to Reversion.......<br />And,.. You'll Never "Feel" the difference......

 

[whitedesigns]

Re: performance upgrade for mercruiser 4.3L

Thanks for the suggestions everyone! I'll give them a shot.<br /><br />-adam

 

[John_S]

Re: performance upgrade for mercruiser 4.3L

I made a quick check in Moore's SBC book. The cam he recommends using 1.6 rockers on, is a stock flat-lifter based cam. It also recommends moving the intake lobe centerline to 110 degrees ATDC, ie adjusting the cam timing. This is to help prevent what Bondo is talking about. On the SBC he says it is good for 5-10 hp. Given you have a V6 and roller cam, you will want to research this allot more.

 

[bluewater19]

Re: performance upgrade for mercruiser 4.3L

I have the 1.6 ratio comp cams magnum Roller rockers on my 4.3 with roller cam and have had no problems with reversion. This is on my 1992 with <br />a edelbrock intake and holley carb.<br /><br />I am waiting until my 2003 is out of warranty to do the same to it.<br />I already have the intake and edelbrock carb.<br />If these mods wake up my newer boat the way they woke up my old one I will be very happy.

 

[QC]

Re: performance upgrade for mercruiser 4.3L

You can find Torque Shift props on Ebay. They are out of production. They end up going for about $400 with the adjustment tools and in good shape.

 

[Jdeagro]

Re: performance upgrade for mercruiser 4.3L

whitedesigns;<br /><br />You obviously want more performance, but what type? What are you using the boat for? <br /><br />Power and Hull efficiency go hand & hand. One without the other has only half the effect at best. <br /><br />Torque Shift props are designed to allow the boat to shift gears. I know very little about them therefore I will not comment. Trim Tabs adjust the Hull configuration to help match the various conditions of operation. You would not expect a lot of performance out of a car with flat tires!<br /><br />Waht is your use of the boat?