assuming the computer used to run these engines is similar to a car. the computer will detect the knocking/pinging and retard the timing to compensate for it. as long as it continues to detect, it'll run in a retard state and you will have some sacrifice in power. I don't think anyone will ever notice a boat running full tune and one running with the timing advance in a retard state, but as mla suggested, this will have some longterm effects on the overall wear of the rings/pistons/valves and seals. most engines today have quite a bit of "safe" room in the tune tho..
went to 2 tuners over the years to get the old mitsu evo's tuned. it was fun to watch the pc hooked up to it real-time detect and retard the ignition when picking up on knocking/pinging. one was on the interstates out by the salt lake city airport and done while driving. tuned the last one to the brink at a shop in portland on a dyno. original baseline dyno was 330hp/310tq. when I left, it was at 363hp/362tq with no other parts swaps, just an ecu tune. shows how conservative the engine tunes can be. sure mike has even bigger gains from diesels and tuners.
Results 11 to 18 of 18
Thread: Fuel For My New Mojo
10-14-2013, 01:33 PM #11'06 Supra Launch 20SSV-gone but never forgotten
10-14-2013, 02:11 PM #12Junior Member
- Join Date
- Sep 2013
- cape cod
Thank you for your help
10-14-2013, 10:09 PM #13
I put 400 hours on my 08 XLV and ONLY ran 87 and it never gave so much as a hic up.Levi
Former owner of a 08 Mobuis XLV, Cat340, 2650 Lbs.
I miss that boat!
10-14-2013, 11:46 PM #14
Fuel For My New Mojo
Sent from my iPhone
2008 Mobius LSV, Gravity III , Wake Plate, Z5, Exile SX65c's, Exile XM9s, Exile XI12D, Exile Harpoon, Exile SM600.1 , Exile Xi800.4.
10-15-2013, 09:39 AM #15
A lot of higher elevation areas (like CO) start at 85 octane for regular...I always wondered why that was and never realized that may be because of the elevation lol.2006 Mobius LSV
Previous ride - 2000 Supra Launch
10-15-2013, 11:18 AM #16
10-15-2013, 12:21 PM #17
i have been told dont waste money on over 89 either as it is calibrated for 89.. if you blend higher with 87 that is worthy, but dont expect any improvements by running 93.
Long running debate on here and wakeworld about 87 v 89. Many of us have done 87 plenty with no noticeable issues.
I ran a couple of Acura TL's that demanded 91 or higher.. was a pain but its all about the compression, computer, etc.
I try to stick to 89 most of the time though.Brad
2011 Launch 21V
2006 Moomba Mobius LSV sold
2004 Outback sold
10-16-2013, 08:32 AM #18
Funny but on my '08 I'm pretty sure my boat manual says run 89 but my Indmar manual says run 87.My Mom said I'm not allowed to get wet!
2000 Outback LS (sold)