Octane boosters??

[kevnmcd]

Trying to get opinions on which octane booster works the best. When we go to Powell next month, I won't be able to get 91 octane on the water (except at Antelope Point, and that will be too far to go to gas up) so I will need to boost the 87 octane up.

What is the best bang for the buck?

TMF - What did you do while you were up there?

[Trouble Maker]

What about Dangling Rope...I think that's where I normally top off at... Just stop being such a lead foot.... lol

[kevnmcd]

Dangling Rope doesn't have 91, only 87. I am not a lead foot :ohboy: my engine builder told me to run 91. :D

Do you think that it will be okay on 87 if I don't run it hard? Oh, who am I kidding....I can't keep from pushing that stick forward as far as it will go! :lookaround: I guess I would rather be safe than sorry.

[Red Horse]

There is this stuff that is made by Berryman Chem tool. It is for offroad use. I used to run 93 plus with this stuff before I got smart and set my timing different. It worked well for me. Kinda hard to find however.

http://www.berrymanproducts.com/Default.aspx?tabid=141

Second one down on the page.

BTW, never hurt any of my hoses, carb stuff, etc that I could tell.

[kevnmcd]

Thanks.

[kimswang]

Kev, are you running a blower, a high compression or an old engine? If not, was the problem with 87? My jet can run on that stuff...

[STV_Keith]

Kevin, I will have more info for you in a few weeks as I am testing some stuff that's supposed to work quite well. I have mentioned it here before...it's called Aces IV (http://www.bndautomotive.com/page/page/960368.htm). This stuff is very potent according to it's info. 1oz of this stuff will treat 6 gallons of fuel and raise the octane by 9 points. It's not cheap, but it supposedly works well.

In the next few weeks, I will be doing some testing on my boat with a cylinder pressure data acquisition system that will be able to show me exactly how much cylinder pressure is in a given cylinder of my engine at any time in the crank cycle. This should allow me to play with timing to see if/when that affects power output and combustion rate. This will tell me how far I can go with pump gas, then let me see the difference going to race fuel and then to pump gas with Aces IV. I plan to test it all.

This should give me a real-world idea of what the stuff is worth, both by HP and by detonation resistance (ie, pump gas is good to 27* timing, but pump + Aces IV is good to 30* timing and makes 10hp more per cylinder).

Hope this helps for now.

[kimswang]

WOW, Keith you are having way too much fun. Can't wait for the result of that test. Sounds like fun. What kinda motor are you testing it on?

[STV_Keith]

The only running boat I have...the STV. :)

[panic button]

Powells elevation is higher, so you would need less octane. Isn't your motor injected? If so, the computer will compinsate for the altitude differance.

[Trouble Maker]

A couple cans of the Berryman wouldn't hurt, but the motor does have a knock sensor and will retard the timing if needed if it senses any knocking going on....

You sure Dangling Rope doesn't have 91octane??

[kevnmcd]

Keith - I will look for your results when you have them. Thanks.

[kevnmcd]

Powells elevation is higher, so you would need less octane. Isn't your motor injected? If so, the computer will compinsate for the altitude differance.

I was wondering if the elevation would help. It is injected and you are probably correct that the computer will compensate...forgot about that.

A couple cans of the Berryman wouldn't hurt, but the motor does have a knock sensor and will retard the timing if needed if it senses any knocking going on....

You sure Dangling Rope doesn't have 91octane??

I am not absolutely positive they don't have 91 but every website I have looked at and even Mardonzi posted on another board that Antelope was the closest with 91. I will probably just grab a couple cans of Berryman and keep them with me just as a little insurance.

[TooMuchFun]

Kevnmcd,

All the marinas up there only sold 87 when I was there including Dangling Rope ... I use Outlaw Octane Boost when I use a boost.

I run EFI and the computer does not completely compensate for the altitude though it tries a bit ... low end to plane is a bit slower at Powell, and WOT is where the altitude difference is really noticed ... I lost about 15 mph off the top end.

The only thing that really compensates is to change out your props to a smaller pitch (to boost the rpms). I have an extra set for this purpose ... brings the low end back to normal and helps with the top end a bit. I forgot to bring them to Powell and was kicking myself.

Have fun up there.

TooMuchFun

[STV_Keith]

Even if the A/F ratio is correctly adjusted, a naturally aspirated engine will lose 4-5% per 1000' elevation increase. You can typically also increase timing by 2* per 1000' elevation...and that does help some.

When I went to work at Dynojet back in 95, we dynoed my '72 Buick Riv GS 455 and picked up 35rwhp with 12* of timing advance above stock at sea level to 5000'.

[kevnmcd]

Thanks, Tom. We will have a good time for sure! I remember when I was there last time...the boat was a little more sluggish out of the hole and did lose a little on the top end. Small price to pay for spending a week on a lake like Powell! :D

Keith - With what you are saying it sounds like I should be fine with 87 octane at that elevation as long as I don't change my timing.

Anyone have a 24p Bravo 1 I can borrow for a week? ;)

[mardonzi]

Kev, Dangling Rope does not have 91 octane. Antelope Point is the only place on the lower lake that does and they are proud of it. What I normally due is purchase avgas and then top off at dangling rope... That way I can run up and down the lake without any adverse effect.

As far as Octane boosters go, I use the offroad version of Boost 104. It seems to run better than the others.

[kevnmcd]

Thanks, Don.