So I'm hearing alot of of rumors on adding small amounts of acetone to save like 10 mpg plus 5% more HP?????? Is this true and has anyone done it in your boat????

save gas I'm not so sure about that but it should increase power. I know i wont be trying it <BR>I have no need to blw the top off my motor. <BR>if you really want to go faster you could just pay for the 121 octane chances are you'll still burn your motor up if you run enough of it. <BR>

I wouldn't do it. A lot of engineering that goes in to the design of an engine. Also use the rule, if it sounds too good to be true it is too good to be true.

How to save on gas? Get more riders, and riders who will help pay for gas. Use less ballast. Guys were doing 80% of the tricks they are doing today behind boats with little ballast and no tower.

from what I've read, its 1-2oz per 10gal.... I've read about alot of folks trying it in their cars..... Was just wondering if anyone had the balls to try it in their boat....

If you need to save gas that bad, please just sell the boat.

Adding octane bust type product to your fuel will do nothing for you on these computer controlled LOW COMPRESSION motors these boats come with. If you look in your Mercruiser manual you will see it states 87 octane is what the computers are designed to run on do to the low 8 to 1 compression ratio of these motors. you can thank the LOW EMISSIONS LAWS for the low HP.

not every marine engine has 8 to 1 compression, mine has 9.1:1 and recommends 89octance

So if you use 93 do you get worse performance than with 89 octane?

no, but you don't get any better performance you spend more money and you have higher emissions

so you are saying your engine of choice would be one that takes 87 octane. what if you have one that requires 89, thats going to cost another $8 per 40 gallon tank and for what benefit. I found out the boat I am going to buy requires 89 <IMG SRC="http://www.wakeworld.com/MB/Discus/clipart/sad.gif" ALT=":-(" BORDER=0> but I don't think this is enough to cancel the deal.

octane is a measure of how quickly the combustion process happens. you can run 87 octane in any streetable engine without detonation if your timing is right, and you're only leaving a couple percent horsepower on the table. i had my car reprogrammed, and one of the changes i made was to go to 87 octane. i still gained about 10-15 hp over stock, and about 1 mpg. it would've been about 15-20 hp if i stayed on premium. <BR> <BR>here's a good real-world test: <a href="http://www.diabolicalperformance.com/hotrodoctane.html" target="_blank">http://www.diabolicalperformance.com/hotrodoctane.html</a> <BR> <BR>i've heard mixed reviews on the acetone thing, but the general consensus was that the gains weren't worth the trouble (and risk of eating rubber stuff if it's too concentrated).

trace <BR>nice thread, that helps out alot <BR>looks like I might be able to tune the motor to 87 octane and run just fine <BR>

Hey Neil. I don't know what kind of boat you're looking at but my Super Air has the PCM GT40 which also is supposedly tuned to run on 89 octane. It also says in the manual it CAN run on 87 if needed, so... Gas was so freakin expensive last season I checked directly with PCM to see whether that engine would be ok running 87 octane. They told me it would be fine on 87. <BR> <BR>It's worth checking on and I wouldn't necessarily count out that boat until you check.

looking at a supra 02 22ssv, just waiting for it to get out of the shop

I'm pretty sure the Supras use Indmar engines and I know the Indmar Predator that MC uses runs fine on 87. Not sure which engine model the 22ssv uses. Chances are, unless it's a high-output or based on the LT1 Corvette block, it will run fine on low-test.

If you use lower octane fuel than what the base timing is set for then you are relying on the knock sensor to detect the ping and retard the timing, If it does not a broken piston is a lot more expensive than a higher grade of fuel.

I want a boat motor that takes E85!

for the record, i was not suggesting anyone run lower octane than recommended by the engine mfr; all i'm saying is it is possible to run safely with proper tuning, which may not be feasible on a boat motor. <BR> <BR>i've talked with Indmar before about PCM programming software, and IIRC it would've been around a grand to get set up to tinker. <BR> <BR>also for the record, i'm not suggesting tinkering unless you know what you're doing. <IMG SRC="http://www.wakeworld.com/MB/Discus/clipart/happy.gif" ALT=":-)" BORDER=0>