All good questions. I'll insert what I hope to be good answers...
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Originally Posted by HWYSTR455
I still question the timing marks on the balancer. Still say you need to verify TDC and the mark. I'm guessing an OE type balancer? Is it used?
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It's an aftermarket balancer with timing marks up to 50*. I don't know the brand but it's black with white marks. I'll take a pic and look for a name but don't recall seeing a brand.
I have not yet verified the marks.
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How are you checking timing, with a dial back light? If so, brand/model?
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I've verified with three fixed style timing lights (no dial backs): my 30 year old Craftsman, my newer model (don't recall the brand) and one of Richie's that he believes to be accurate.
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55+ sounds like an awful lot to me, but maybe because it's a low-9 something SCR is why. And 36 at idle sounds like a lot too. Usually 20-24 is max that I've seen work well.
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According to the people that believe in using MVA, I followed their directions on how to establish good MVA timing. Basically, you find the sweet spot of timing that the engine likes by turning the distributer at idle with vacuum disconnected and plugged, and watch the tach for the RPM's highest point and then note that timing number. For me it was 36* (and the car liked that). So starting at 12* initial, the idea is to add back in the 24* of timing with MVA. This means your cruising timing is also higher by that 24*, hence the number in the 50's. Several books also talk about 50+ degrees as a common cruising timing figure.
And remember, I've tried ported advance it the car hates it.
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Originally Posted by STEELCITYFIREBIRD
I'd be curious to disconnect and plug the vacuum line and take it for a ride.
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I was too. So I did just that. Car runs fine without an vacuum advance (no ping anywhere) but is not nearly as responsive down low, it has a lumpy idle and the exhaust is smelly and MPG.
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If it likes a bunch of initial advance,I'd take some out of the mechanical advance,or go lighter on the springs and use the vacuum can, ported, for fuel mileage at light throttle cruise.
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Don't follow you there but I think that's what I'm basically trying to do with my vacuum advance. I can't start the car with more than about 14* advance.
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Does the carb respond well to adjusting the idle mixture screws? You can stall it by closing them and make it stink fire by opening them too much?
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It's a brand new Cliff Ruggles carb and I have not touched it one bit yet. He had all the specs on the engine when he built the carb this winter. I will reach out to him but was waiting for some time to pass given her personal life situation with his dad and all.
But yes, my next thought it that the car is running well at current settings except for the surging at steady part throttle, so maybe it's time to richen the idle circuits. Hopefully that's just the idle screws. I don't want to mess up this carb.
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Adam
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1964 LeGTO
469, M21, 3.42
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