BBC Timing
#11
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I don’t know where your initial is but msd largest bushing is 18 degrees which makes going into gear a bit challenging as your base will be 16. I recently put in a 14 degree bushing and have my base at 20 and it’s a lot happier. I did buy a Daytona control box but may not install it now. Just some food for thought. Not sure what ignition you are running.
#12
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Thread Starter
I bought the ready to run MSD distributor for marine use. My dyno guy installed the "black bushing" and I believe he used the lightest and the medium springs for the advance. He knew it was for a boat and I did mention that I need / want it to behave around the docks.
#13
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Heads and cam play a big part with timing. Mine were set to 42 degs when I bought the boat. Ran it like that for 2 seasons before I put a timing light on them. Pulled plugs and no detonation was found. Dug into the distributors (MSD) and found springs rusted/missing and mech adv stuck at full advance. Freed them up and replaced springs. Set to 36 degs total. Starters are much happier. Lost a couple of MPH on the top end. Normally, I agree 36 degs total should be max but there are exceptions.
#14
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I bought the ready to run MSD distributor for marine use. My dyno guy installed the "black bushing" and I believe he used the lightest and the medium springs for the advance. He knew it was for a boat and I did mention that I need / want it to behave around the docks.
#15
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Thread Starter
Yup, I think they came with a couple different bushings and springs. The dyno guy says that this is always the first thing he does is swap out what ever bushing for the black bushing. If you look at my posts, you know that I'm no mechanic. So I say this as a question: I don't know if it matters or not but the dyno guy said it has a ton of vacuum at idle. Does that mean it should handle the load of in and out of gear better? He knew these were going in a boat and I told him that I needed them to be good around the docks etc. These are not crazy builds and the cam I understand is pretty mild and on a 112 degree lobe separation. I'm hoping it works as is. If it gives me trouble, this will be the first thing I look at. Thanks for your help.
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PQ290Enticer (01-08-2023)
#17
I played around with big timing on the upper end with VP110 as a safety net so to speak. No extra performance measured. 32-36 seems to be the best all around number. Where I did experience very noticeable gains in regards to timing was coming up on plane in the 2200-3200 rpm band. If set too low (about 22-24 in my case) boat felt sluggish getting on plane. Just a few more degrees and it really woke up and was almost like a new motor when coming on plane. So I would put as much timing as the motor allowed in that rpm band that didn't cause detonation.
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PQ290Enticer (01-28-2023)