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#1
10-03-2023, 12:06 AM
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Timing curve rate and all-in point?
Still tuning the 400. It's a 69 400 with 62 heads. I think it's stock except for the Summit 2802 cam, RPM intake and headers. It's got a 10" converter that's a bit on the loose side, a TH400 and 3.25 gears. Stab it, and the converter flashes to 3500. 93 octane. How aggressive can i get with the timing curve, without risking pinging?
It runs pretty well now, but I'm fighting some mild overheating at cruise. I suspect the cooling system but want to rule out the timing. It's 16* base, 19* of mechanical advance, 10* of vacuum advance. MSD RTR distributor. So that's 35 mechanical plus the 10* of vacuum. The curve is kinda slow, it isn't fully advanced until 3500 RPM according to the MSD chart. The overheating I'm seeing is 2500-3000 cruise. Temp rises from 180 to 210 on the highway and slowly cools off as I slow down. Plugs are clean and it runs pretty crisp. It's an old rebuild, lots of miles, but doesn't use oil, has good compression, clean as a whistle in the lifter valley. It had a mallory unilite with two heavy springs and a VERY slow curve when I bought the car. Is it good where I've got it or should I bring the timing in a bit sooner?
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I could explain all this to the girl at the parts store, but she'd probably call the asylum. White '67 LeMans 407/TH350/Ford 3.89... RIP Red '67 LeMans. 407/TH400/Ford 3.25 |
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#2
10-03-2023, 06:11 AM
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Do a search for the paper titled Spark plug reading 101 and print it off. It's by Mike Canter
You will certainly want to get what you have needed for a long time after reading that, that being a Spark plug magnafing light.
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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#3
10-03-2023, 08:29 AM
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Have you verified you’re getting the VA at cruise? Otherwise you should be getting plenty of airflow through the radiator at speed. Unless you have one of those electric fan deals with the flat fan shroud that blocks lots of the air flow.
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Will Rivera '69 Firebird 400/461, 290+ E D-Ports, HR 230/236, 4l80E, 8.5 Rear, 3.55 gears ‘66 Lemans, 455, KRE D-Ports, TH350, 12 bolt 3.90 gears '64 LeMans 400/461, #16 Heads, HR 230/236, TKO600, 9inch Rear, 3.89 gears (Traded) '69 LeMans Vert, 350, #47 heads: Non-running project |
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#4
10-03-2023, 12:37 PM
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Quote:
The electric fans likely fit your description. Here is a link to them: https://www.summitracing.com/parts/s...SABEgLHffD_BwE They were on the car when I bought it. I'm not a huge fan (haha) of the electrics but so far they work. Will a 19" fan and fan clutch from an AC car, fit the non-AC radiator? I have one of them I could try.
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I could explain all this to the girl at the parts store, but she'd probably call the asylum. White '67 LeMans 407/TH350/Ford 3.89... RIP Red '67 LeMans. 407/TH400/Ford 3.25 |
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#5
10-04-2023, 01:53 AM
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Quote:
If everything is lined up properly you end up with just a fairly tight hole in the shroud.
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Mick Batson 1967 original owner Tyro Blue/black top 4-speed HO GTO with all the original parts stored safely away -- 1965 2+2 survivor AC auto -- 1965 Catalina Safari Wagon. |
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