12-07-2007, 06:28 AM #1
Timing curve On Stock ING 1200gpr
Timming curve On Stock ING 1200gpr...??? Does any one have the graph? If I remember correctly the stock curve retards at around 5000 rpms? any one have that curve graph?
12-07-2007, 08:14 AM #2
- Join Date
- Apr 2006
- panama city beach 'fl
12-07-2007, 08:47 AM #3
OEM curve is # 83. Most popular Advent curves are 59 and 84 for the single pipe boats.
12-07-2007, 10:10 AM #4
- Join Date
- Jan 2006
Makes an interesting reading
ie at 7000 rpm degrees advance
#3 = 9, #2 = 12 & #1 = 12
84 and 59 curve
#3 = 16, #2 = 20 & #1 = 23
so adding atleast 6 degrees advance at 7000rpm, which make the 3 degree key look quite conservative on the EFI skis.
12-07-2007, 01:06 PM #5
Problem with 3 degree keyway is the timing at 5000. OEM curve is 24 degrees across the board. The pretty radical 84 curve has 26, 26, 21 @ 5k. To add to that most 3 degree keyways fit lose and you can actualy end up with 5 or more degrees of advance, simple math shows close to 30 degrees at 5000 before the valves open.
The results are incredable acceleration with improved top end but when you back off the throttle after a hard run it superheats the piston and sticks in the bore. Been there, done that, tried it again, etc.. Even lowered compression to 130 and it still stuck. Only way to make it live is race gas.
EFI curve is much different then the 1200 and is why it can survive in those boats.
12-07-2007, 07:30 PM #6
Cool man that's the info i was looking to get.. I was looking at it when the vast info over loaded my little daughter.
just talkng timing curves gets her worn out!
12-07-2007, 07:46 PM #7
So Is the stock curve close to 83?
that is what i am looking to find? i want to see if the stock curve is playing a role in the hole shot " lack of gain" i am running into?
like i hit the throttle out of the hole, it pulls great for 40 ft then like slows the accerleration for a sec or 1.5 then pulls hard. it never misses a beat, it just isn't gaining speed as fast as it was.
all i have is a 3* key way right now for timming.
i believe that this advent would do some wonders on it with some bigger voltage coils
12-07-2007, 11:03 PM #8
12-07-2007, 11:16 PM #9
12-07-2007, 11:45 PM #10
My 1200 ran great with the stock ignition, no key. The bigger bore may change things a little. If you are feeling a dead spot it may be power valve related. Do you have gas or electric valves? If the valves are gas you may want to tighten the springs a little and try it. If it is electric try unplugging the servo and running with the valves down then run with them up see if you change the flat spot (move it). Has it always had the late bog or did it develop it. If it is a new development I would certainly look at the powervalves first then carburetion.
Yam 59 is my favorite Advent curve
I just want to make sure you exhaust other things chasing the demons before you drop $550 and need to remove your 3 degree key and the same problem still exists.
Did you get the high pressure pump and dynafly? V-Force reeds?
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