Like Tree0Likes

Two questions?

Reply
Old 09-27-2008, 01:35 PM
  #1
Registered
Thread Starter
 
Join Date: May 2008
Location: Summerville, SC
My Boats: 1994 Fountain Fever 27'
Posts: 127
Default Two questions?

1.Do any of you guys run Av gas in your boats? Other than the price are there any disadvantages?

2. Do any of you guys run the MSD Boost timing master or the adjustable timing control on your engines? I am thinking about buying one of them because it is kind of a PITA to adjust the timing when the headers are hot.
bruin_d is offline  
Reply With Quote
Old 09-27-2008, 02:26 PM
  #2
Registered
 
gsmith9898's Avatar
 
Join Date: Mar 2005
Location: tulsa, oklahoma
Posts: 1,870
Default

I have used the msd boost timing master on my vette. Works great, with just a turn of the knob.
gsmith9898 is offline  
Reply With Quote
Old 09-27-2008, 02:53 PM
  #3
Registered
VIP Member
 
Join Date: Jan 2004
Location: Boca Raton, FL
My Boats: None
Posts: 3,682
Default Long ago and far away...

many moons ago Howard Quam and I used to burn aviation fuel in "Flap Jack". We had the old Kinsler timed fuel injection and rather than risk messing up the o-rings in the pump, we added oil to the fuel.

Aviation is very high in alcohol, (very dry), and it does attack rubber components.
Edward R. Cozzi is offline  
Reply With Quote
Old 09-27-2008, 03:29 PM
  #4
Registered
 
hunster's Avatar
 
Join Date: Feb 2005
Location: oceanport nj
My Boats: 94 scarab 29
Posts: 1,626
Default

Too much octane is not always a good thing.
hunster is offline  
Reply With Quote
Old 09-27-2008, 04:21 PM
  #5
Rob
VIP Member
Trade Score: (6)
 
Strip Poker 388's Avatar
 
Join Date: Aug 2001
Location: Madison,Mississippi
My Boats: Hustler 388
Posts: 21,567
Default

what if you used the av gas as a booster,like making 93 a couple points higher,a cushion on detonation.
__________________
.

The Only Time You Have To Much Ammo Is When Your Swimming Or On Fire.
Strip Poker 388 is offline  
Reply With Quote
Old 09-27-2008, 04:23 PM
  #6
Registered
Thread Starter
 
Join Date: May 2008
Location: Summerville, SC
My Boats: 1994 Fountain Fever 27'
Posts: 127
Default

Quote:
Originally Posted by Strip Poker 388 View Post
what if you used the av gas as a booster,like making 93 a couple points higher,a cushion on detonation.
That was kind of my idea behind it.
bruin_d is offline  
Reply With Quote
Old 09-27-2008, 04:30 PM
  #7
Registered
Thread Starter
 
Join Date: May 2008
Location: Summerville, SC
My Boats: 1994 Fountain Fever 27'
Posts: 127
Default

Quote:
Originally Posted by Edward R. Cozzi View Post
many moons ago Howard Quam and I used to burn aviation fuel in "Flap Jack". We had the old Kinsler timed fuel injection and rather than risk messing up the o-rings in the pump, we added oil to the fuel.

Aviation is very high in alcohol, (very dry), and it does attack rubber components.
How well did the kinsler injection work? I have always want to try something like that or a Hilborn setup on one of my toys. I love the way they look.
bruin_d is offline  
Reply With Quote
Old 09-27-2008, 10:09 PM
  #8
chuckbeecher
Platinum Member
 
Join Date: Jun 2001
Location: Anywhere from the Laguna Madre to JAX and beyond
My Boats: glasstream
Posts: 1,259
Default

Av gas use to burn a lot hotter and could be a problem with burnt valves and such.
chuckbeecher is offline  
Reply With Quote
Old 09-27-2008, 10:49 PM
  #9
Registered
Trade Score: (3)
 
Join Date: Apr 2006
Location: Toledo Oh
My Boats: 22 Avanti, 25 Nova, 2 turtle doves and a partridge in a pear tree,SBYC
Posts: 8,667
Default

gasoline isn't simply gasoline. it's a mixture of many different things. aviation anything is fairly specific.. avgas is designed/formulated to run in moderate hp engines in a semi-oxygen deficient environment at a moderate consistant sustained RPM and a relatively cool air supply. it contains, among other things various anti icing additives plus the carbs have heatng elements to additionaly combat icing (how do I know this, my father ended up in a farmers field because he forgot to flip the switch) could you get away with running it? probably, is there a risk? yes. is it an acceptable risk? thats your call. race fuel is expensive, but it does come in much higher octane than avgas 112-116 vs. 100 so it can be diluted with regular fuel offsetting the cost. HTTP://www.bazellracefuels.com/Calcs/OC1.htm contains a calculator for figuring out octane mixing ratios. it is also important to know what octane you actually need, not what you think youneed or want. To high of octane will actually DECREASE power.
phragle is offline  
Reply With Quote
Old 09-28-2008, 12:59 AM
  #10
Registered
 
Join Date: Sep 2008
Posts: 105
Default

Here is my two cents, Av gas is formulated for laege bore, long stroke, low rpm engines which run at higher altitude. Av gas gigher octane is usefull for that, but it has a lower volitility so part throttle response sucks. It has a lower spific gravity so it will require a jet change or ecm tune. Av gas has a higher percenage of aromatics. That reduces throttle responce. Also Av gas octane numbers are not computed the same as motor octane numbers of race fuels and it is short on octane compared to race fuels. Many marine engines run more spark advanceat low to mid throttle than av gas and some unleaded fuels can handle. The rsult is detination. the bottom line is if your not over 10.5:1 your wasting your money. You should stick to good grade pump gas and tune to it. That will get you the best perfomance your engine can produce. Unless you use a hydometer and keep track of the specific gravity of your fuel mix your tune will always be off every time your fuel mixture changes.
RHM253 is offline  
Reply With Quote
Reply

Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
stevesxm
General Q & A
1
06-28-2007 11:03 AM
OkieTunnel
General Q & A
7
03-08-2006 04:21 PM
buck183
Active Thunder
3
05-16-2004 06:48 PM
Red Stripe
General Q & A
7
05-28-2002 07:48 AM
mama tryed
General Boating Discussion
23
02-12-2002 07:21 PM



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 10:30 PM.


Copyright 2011 OffShoreOnly. All rights reserved.