Attack of the bad gas! (Solved)

ric · **Posted:** Tue Aug 27, 2013 9:48 am

deafwish wrote:

ric wrote:

Well, I just got offered a contract today for good ass money. I do VOIP work. I'm going to go ahead and swap it over to an edelbrock performer manifold, holley marine 600cfm carb with the GM Performance 350 RAMJET crate motor camshaft in the next few weeks. It's the same camshaft in the Mercury 350MAG MPI. In the automotive world that combo on Vortec 305's brings them to around 350hp and 400lb torque. It's 220 right now. With the vacuum secondary holley it should actually get better GPH than with the mercarb.

Do you plan on upgrading to a better designed exhaust manifold or staying with OEM?
I trust you're doing the lifters, pushrods & springs with this upgrade? :wink:

Don't have to, I'm using the OEM camshaft from GM. Mercruiser installed a detuned cam. It's lift/duration is well within specs of what the stock valvetrain can handle (under .450 lift).

I'm basically turning it into a 5.0 liter 5.7GXi or 350 MAG MPI.. minus the fuel injection and .7 liter. The 10-20hp I loose from the smaller displacement I make up with a good intake and carb.

If you want to get technical, I'm actually just bringing the motor back to GM crate engine stock spec and removing mercruiser's detuning, just "upgrading" the cam from the stock 5.0 to the better stock 5.7. They do that to justify the different engine levels. The 5.0 comes standard with 270hp and the 5.7 comes with 340.

rpengr · **Posted:** Tue Aug 27, 2013 4:03 pm

ric wrote:

...In the automotive world that combo on Vortec 305's brings them to around 350hp and 400lb torque...

Well you'll lose about 30 HP on the way to the propshaft,
and another 20 HP to those cast iron manifolds (unless you can get Deafwish to send those Aussie Hi-Tech SST header-manifolds to you)

Winter Sux · **Posted:** Tue Aug 27, 2013 5:07 pm

You'll never see that kind of HP increase ric. Add on performance parts will boast HP increases based on a variety of other engine components AND the condition of such; meaning, compression 100%, an exhaust system that will allow the engine to exhale, roller lifters, roller rockers and a myriad of other things as well.

Also, where the hell do you come up with better gas mileage by using a vacuum progression 4 barrel? A 600 CFM vacuum progression will only give you better mileage for a few seconds till the secondaries are wide open. 600 CFM is 600 CFM whether it's vacuum or mechanical progression.

I'm sure you'll prove me wrong though once you've had your build dyno'd.

MikeZ0759 · **Joined:** Mon Aug 26, 2013 8:03 am **Posts:** 7

If it were only this easy. I built several marine and auto small blocks and a cam and intake and carb will not give a 305 a 130hp and 180ftlbs of torque. Maybe with a set of heads. And stiffer springs are a good idea if your gonna be spinning those R's

298VISTA2000 · **Posted:** Tue Aug 27, 2013 8:54 pm

This thread is hilarious.

ric · **Posted:** Tue Aug 27, 2013 9:20 pm

It's a vortec 305. It has roller cam, good heads, etc. It's factory rating with just a normal carb is 270hp. I'm only gaining 30 to 50hp with a good intake, good carb, and good cam. That's not unheard of at all in the vortec SBC world. In fact that's low. If this was a vortec 350 (5.7GL) it would be in the 400hp range.

Look them up. 340hp out of the vortec 305 with what I'm doing is actually quite conservative.

TX H210SS · **Joined:** Thu May 27, 2010 9:10 am **Posts:** 1488

Out of curiosity....Why?....is the Chap not performing up to expectations? Seems like stock should be more than enough for that setup. I can see it if you were to have a malfunction that required part replacement, but based on this thread you only need a Carb rebuild due to ethanol woes.

But hey..its yo money and boat, but it seems to me once you start jacking with factory setups it causes a chain of probs unless you go all the way.

LouC · **Posted:** Wed Aug 28, 2013 7:57 pm

Dude I'd forget all that expensive stuff and go and get your gas tank professionally cleaned or else you are going to be chasing that gremlin the whole time you have that boat. Start with and verify the basics are sound, then you can go off on mod tangents.
I have to say once I went through that change over phase from MBTE gas (that was the oxygenate that was getting into the water supply and is very hard to remove, ironic because it was added for enviro reasons) to E-10, I did not have on-going problems with it. I do dump out the fuel filter each fall and look for water in the gas after it sits but none to be found thank goodness.

298VISTA2000 · **Posted:** Thu Aug 29, 2013 7:32 am

ric,

Why don't you just go back to running regular, non-ethanol gas? All my problems went away after I did that (and after going through 6 fuel filters and two fuel pumps). Think of all that varnish that is still in the fuel tank and engine system that is 10 years old. It will be never-ending.

LouC · **Posted:** Thu Aug 29, 2013 9:42 am

The thing is that if there is a bunch of crap in there once the ethanol loosens it up it's better to clean it out. I had my fuel sender unit out this fall (after Sandy had to siphon gas out for the home generator ) and it was still clean down there. Maybe the old school boats with carbs and mechanical fuel lumps can handle this stuff better.
It reminds me of the days when (1968-70) German cars were going to fuel injection (both the mechanical and newer electronic systems) . Our gas wreaked havoc with those systems till the right detergents were added. Meanwhile my old school cars with carbs were just fine.

Cap'n Morgan · **Posted:** Thu Aug 29, 2013 12:34 pm

Some "fuel additive" related news released today, that is loosely related to the original thread title. Read if you are interested.

Quote:

Alcohol-Free Additive Extends Storage Life of Ethanol-Blended Fuel and Protects Engine

(CHESAPEAKE, Va.) Aug. 29, 2013 – (Marine NewsWire) Volvo Penta of the Americas now offers a fuel additive to protect marine engines from the harmful effects of fuels containing ethanol.

Volvo Penta Ethanol Fuel Treatment is suitable for any outboard or sterndrive system and is strongly recommended for use every time you fill up with ethanol-blended gas to protect your engine from damage.

“Ethanol-blended fuels such as E10 and E15 are approved by the U.S. Environmental Protection Agency for the automotive market, but ethanol damages marine engines and fuel systems due to the corrosive properties of alcohol,” explained David Kennedy, Director Parts and Accessory Operations, Volvo Penta of the Americas. “Unlike automobiles, most marine engines are only operated intermittently. Today’s oxygenated and ethanol-blended fuels can begin to oxidize in as little as 30 days if left untreated in the boat’s tank, resulting in corrosion inside the engine and fuel system.”

Volvo Penta Ethanol Fuel Treatment contains special antioxidants to combat fuel breakdown and also contains chemical corrosion inhibitors that form a protective barrier on fuel system components. It has been engineered, tested and approved by Volvo Penta to prevent fuel degradation and keep marine engines running smoother and more efficient. It also helps enable easier starting, maximum power output and optimal fuel economy.

“Importantly, our Ethanol Fuel Treatment is totally alcohol-free and helps ensure longer life and better performance for marine engines,” said Kennedy.

rpengr · **Posted:** Thu Aug 29, 2013 1:15 pm

Cap'n Morgan wrote:

Some "fuel additive" related news released today, that is loosely related to the original thread title. Read if you are interested.

Thanks Cap'n,
Here it is:
http://www.marinepartsexpress.com/Ethanol_Fuel_Treatment.html

$6.98 per bottle at Marine Parts Express: http://www.marinepartsexpress.com:8080/mpeCart/details.faces?productId=22203959

rpengr · **Posted:** Thu Aug 29, 2013 1:26 pm

Quote:

E10 is certainly not as trouble-free as E0, especially the first few tankfulls. But for newer engines, those built after about 1991, there's no reason the initial problems can't be overcome. No less an authority than Mercury Marine says, "After the transition period from E0, E10 may actually be a superior marine fuel as it tends to keep low levels of water moving through the fuel system, keeping the system 'dry.' "

http://www.boatus.com/magazine/2011/december/ethanol.asp

298VISTA2000 · **Posted:** Thu Aug 29, 2013 7:58 pm

I still think that if ric goes back to regular non-ethanol gas, it will "stabilize" matters. Otherwise, he will be de-varnishing a 10 year old system for years.

I do feel for you ric due to the loss of your season that was brought on by nothing more then a government mandate. Just wait until Obamacare hits because what you are going through now is a cake walk compared to that government mandated fiasco.

ric · **Posted:** Thu Aug 29, 2013 8:52 pm

I'm a canadian citizen (dual american). I don't think Obamacare effects me

www.iFourWinns.com

Attack of the bad gas! (Solved)

Who is online