300xs year differences

**TraceF3** · 10-03-2018, 10:00 AM

Originally Posted by NICE PAIR

What chu got Willis? Whose really works? ;-)

Search. Lot's of people on here using primarily one brand.

**kct11** · 10-03-2018, 10:17 AM

Aces is supposed to be good. I have no experience, but hear people rave about it.

**NICE PAIR** · 10-03-2018, 05:18 PM

Originally Posted by kct11

Aces is supposed to be good. I have no experience, but hear people rave about it.

I have used ACE's, seemed to do the job. I've been told its not an octane booster, rather a detonation deterrent.
I thought someone may have an octane booster they had experience with and recommended.

Thanks everybody. NP

**FMP** · 10-03-2018, 07:03 PM

I can say these work, don't have your motor but anything with fresh MMT like
http://race-gas.com
http://www.royalpurpleconsumer.com/p...el-stabilizer/
Five gallons of toluene into 25-30 gallons fuel will also do it

**NICE PAIR** · 10-03-2018, 09:38 PM

Originally Posted by FMP

I can say these work, don't have your motor but anything with fresh MMT like
http://race-gas.com
http://www.royalpurpleconsumer.com/p...el-stabilizer/
Five gallons of toluene into 25-30 gallons fuel will also do it

They have phone numbers ... I will be calling.
I will be almost out of 85/91 mix by the time I reach my destination. I'd need 20 gallons of toluene to mix 120 gallons of 85.

Thank-you, NP

**FMP** · 10-03-2018, 09:47 PM

Thats getting ^$! , at 85 the 1oz/gallon MMT only gets you to about 87. The race uses more in their directions and has the higher concentration version.

**NICE PAIR** · 10-04-2018, 08:23 AM

Originally Posted by FMP

Thats getting ^$! , at 85 the 1oz/gallon MMT only gets you to about 87. The race uses more in their directions and has the higher concentration version.

Thanks, does anybody have an opinion about running a pair of 300XS's on 85 octane, loaded light, 28 props, under 5000rpm.

**XstreamVking** · 10-04-2018, 08:38 AM

My opinion is, knock,knock, who's there? New power head that's who......But, I was the village idiot that thought the 300 XS motors self corrected for octane. I believe from what I have read 89 and you might be ok. Below that and it's a no go.

**marks86** · 10-04-2018, 08:38 AM

I wouldn’t do it, unless I had to. I mean really had too. I won’t even run 91 In mine. I totally understand that it might be possible.

for the amount of money these motors cost not a chance I’m willing to take. If your taking a trip that takes you too a place that only has 85, I would cancel the trip. That’s just my opinion.

**Davidlake** · 10-04-2018, 08:45 AM

NP, Is there an an airport close to any of your stops? You could contact the FOB and maybe get the staff to deliver 10 gallons of 100LL to mix with your 85 at a marina. Far fetched, but maybe an answer. Or get your seaplane buddy to stop at the marina and siphon some av gas out of it?

**FMP** · 10-04-2018, 09:02 AM

Heck leave the boat at home, use the float plane. Call the airport have my plane ready!

**V-bottom** · 10-04-2018, 09:12 AM

Originally Posted by NICE PAIR

What chu got Willis? Whose really works? ;-)

I have used the klotz octane booster. It actually says with boost gasoline by up to 10 numbers. I keep this with me to use in situations where I can only get 89 and have had no issues when using it.

http://www.klotzcanada.ca/images/pro...dfs/KL-602.pdf

10 Best Octane Boosters - Oct 201873 Reviews Scanned

RANK		PRODUCT NAME	SCORE
1		Klotz Octane Booster KL-628 By Klotz	9.7

**TraceF3** · 10-04-2018, 09:17 AM

Originally Posted by NICE PAIR

Thanks, does anybody have an opinion about running a pair of 300XS's on 85 octane, loaded light, 28 props, under 5000rpm.

When I bought my 300xs I had +100 gallons of 87 octane fuel still in my 140 gallon tank. I posted a similar thread.

Finally got the idea to call Mercury customer service. The guy I spoke to said run it; the computer will adjust for it. He also said don't expect the same performance as premium fuel. The motor needs 91 octane to make 300hp.

I'll also add that you could probably call them 5 times and get different answers. So you may consider calling them for yourself.

BTW- my motor is a 2014. Not sure that matters but that's what I told them.

**FMP** · 10-04-2018, 09:18 AM

Pb, it says not alcohol compatible, does that include 10%? Be good with 91 shell and 10% toluene! Wouldn't need to mix too much of it

**Davidlake** · 10-04-2018, 09:31 AM

Originally Posted by V-bottom

I have used the klotz octane booster. It actually says with boost gasoline by up to 10 numbers. I keep this with me to use in situations where I can only get 89 and have had no issues when using it.

http://www.klotzcanada.ca/images/pro...dfs/KL-602.pdf

10 Best Octane Boosters - Oct 201873 Reviews Scanned

RANK		PRODUCT NAME	SCORE
1		Klotz Octane Booster KL-628 By Klotz	9.7

With all my research on octane boosters, I have found, when reading the fine print, that a "point" is 0.1 increase in octane. 0.1 x 10 = 85 octane to 86 octane. Not worth it, IMO.