So today I took the boat to Castaic Lake and set my timing at idle, which was set at 10 btdc up to 15btdc. While checking it w/ engine warm and in the water, around 3k rpms it only got to about 30.
Now I know I have asked about this before, but I am trying to find out if this is good or if I should move up the initial or put in a lighter spring in my MSD pro billet distributor.
I probably want all my advance in around 2500 rpm considering the boat only spins about 4600, right ?
After advancing the timing only 5 degrees at idle, the boat really woke up !!! :supp:
And the second part of this questions is, why at idle sometimes it will idle higher than others, I have 2 return springs, but why would it be higher sometimes I let off the gas than others ? Carb problem ? Floats are good and the mixture smells sweet.
I guess I have another question for the gurus while I'm at it, how accurate are those Summit fuel pressure guages ? At idle my fuel psi is around 2-5 and on the top around 8.5 psi. Is that fluxuation normal or could it be the guage ?
Sounds like you need the advance recurved, should have 38 degrees total all in by 2500-3000 with 12 initial for a nice smoothe operation!..The variation in idle is probably from the weights sticking in the distributor, should have stuck with the factory electronic ignition!....Don't see anything wrong with the fuel pressure, just don't go above 8.5 though!..
The stock distributor took a poop on me and, I know this sounds like a dumb reason, but when the dist tanked, the MSD was the only thing I could find to get me back on the water.
So I'm looking at putting in the lighter springs then, or maybe just one lighter one.
As far as the idle timing being at 15, is that too high ?
As far as the idle timing being at 15, is that too high ?
My timing at idle is at 32 degrees BTDC (you can't have too much...but it can get to be be a pain to start without a start retard module).
On the idle issues, I'd also possibly look at the carb- I had them do that when they needed a rebuild.
It was just rebuilt last season and had lots of attention paid to it from TPC, lets hope the work he did held up one season.
I am thinking of putting the timing a little higher to get more scoot out of the hole, but I think I need to put a lighter spring to jump up quicker.
My timing at idle is at 32 degrees BTDC (you can't have too much...but it can get to be be a pain to start without a start retard module).
On the idle issues, I'd also possibly look at the carb- I had them do that when they needed a rebuild.
Maybe that timing setting at idle is ok for a tugboat......
The stock distributor took a poop on me and, I know this sounds like a dumb reason, but when the dist tanked, the MSD was the only thing I could find to get me back on the water.
So I'm looking at putting in the lighter springs then, or maybe just one lighter one.
As far as the idle timing being at 15, is that too high ?
No 15 is ok as long as still cranks easy, but set your total first then look at the initial, if it's 15 you're ok then check the advance, it should be all in by 2500 or if you want to simulate being locked out, have it come in just above idle, say 1800 that way you'll still have easy starting. You'll have to play with springs and maybe different weights also!..
so 38 degrees at 2500 rpm isnt bad for the motor and probably wont cause any detonation ?
What is the most RPM's anyone has added to WOT by adjusting timing alone ?
so 38 degrees at 2500 rpm isnt bad for the motor and probably wont cause any detonation ?
What is the most RPM's anyone has added to WOT by adjusting timing alone ?
Didnt notice anyware if you said what compression your running? High comp/lots of timing may not be a good combo on pump gas? Max 4600 rpm means its probley kida a stocker? I tried my timing from 32-38 total and found my best performance was at 34, my best idle was with 16 initial. Best thing is to throw a vacume gauge on it and use that to tune the carb. As for the inconsistant idle, probley dont have heavy enough springs in the distributor and they're not pulling the advance back at idle. Same thing happend on mine and the heavyer springs took care of it.
BK, the motor is fairly stock. It has the low-po heads but I did deck the block and use no gap rings, but I doubt its any higher than 9.75:1 and I use pump gas, but I use 91.
As far as the springs not pulling the dist back, I have the heaviest springs in there right now, that is why the timing doesnt jump up real high till higher rpm's.
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