I had found a list of Mercruisers revised timing curves that I had saved in my phone until it decided to crash & wipe out all my bookmarks.
I've searched everywhere & can not find that information. I'm pretty sure it listed a different curve for my setup than what the manual shows but can't remember what it was.
Does anyone know where to find that information or know what my curve should be?
I've got a 79 260 Mercruiser that I just rebuilt. I'm running a MSD pro billet electronic distributor with a 6 series MSD box. The cam is a comp grind #CS XM 262H-12 installed straight up. The manual shows 8? initial with a total of 30?-34? in by 3800 RPM. I'm running a green bushing & a light silver & a heavy silver spring in the distributor which MSD shows to give me 31? total & it's in right at 3700 RPM. It runs good but just feels like something is holding it back a little. I always liked my timing in a little sooner than 3800 but those were not marine applications. This is my first boat with a V8 so I'm learning a lot about the difference in tuning & performance from an auto to a marine setup.
I'm in the process of trying to determine what prop she likes so maybe it will feel better once I get that ironed out. Last time I had it out to check the props I have the plugs were fouled & my cap & rotor was shot & it took all she had to get up on plane running that rough. I've got everything replaced (maybe that's why she felt a little sluggish before) but I haven't had good enough weather to get back to the lake since then. Hopefully tomorrow I can get up there & get some run time on her.
Thanks.
Jim
I've searched everywhere & can not find that information. I'm pretty sure it listed a different curve for my setup than what the manual shows but can't remember what it was.
Does anyone know where to find that information or know what my curve should be?
I've got a 79 260 Mercruiser that I just rebuilt. I'm running a MSD pro billet electronic distributor with a 6 series MSD box. The cam is a comp grind #CS XM 262H-12 installed straight up. The manual shows 8? initial with a total of 30?-34? in by 3800 RPM. I'm running a green bushing & a light silver & a heavy silver spring in the distributor which MSD shows to give me 31? total & it's in right at 3700 RPM. It runs good but just feels like something is holding it back a little. I always liked my timing in a little sooner than 3800 but those were not marine applications. This is my first boat with a V8 so I'm learning a lot about the difference in tuning & performance from an auto to a marine setup.
I'm in the process of trying to determine what prop she likes so maybe it will feel better once I get that ironed out. Last time I had it out to check the props I have the plugs were fouled & my cap & rotor was shot & it took all she had to get up on plane running that rough. I've got everything replaced (maybe that's why she felt a little sluggish before) but I haven't had good enough weather to get back to the lake since then. Hopefully tomorrow I can get up there & get some run time on her.
Thanks.
Jim
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