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Discussion Starter #1
The other day when the temps were around 90 or so, took the '66 Lemans drop-top(455,Carter 625cfm,with 7147 metering rods-runs the car good,but yes,a tad small) out for a spin. On the highway, The temp. ran dead at 180. On the feeder roads, around 190. pulled into the driveway and let it run-was at 210 and climbing. Was near 230, and shut it down. Took a long time to cool. Today, took her for a short romp, (outside temps were 88 in the sun, 74 in the shade). she ran at 180. Set the parking brake in the driveway and let her idle in gear for about 15 minutes. Ran at 195. shut it down and came back after 10 minutes fully expecting the temp to be around 230+ like the other day, but was surprised to see it at 205. As soon as I started it, the temp actually went down to like 170-[NEVER seen that before] then came up to 180 and stayed there steady as a rock. What gives? Would it help if I bump the timing ahead a couple of degrees? Do I need to run bigger jets and rods? I've gone through all the old problem solving methods-cast iron impeller water pump,closing the gap on the pump plate, new radiator,etc,etc,etc...(went through all that with the 326) I just want to make sure this sucker isn't going to start running 220 when the ambient temperature gets to be 95... thanks
 

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Sounds to me like a possible intermittant stuck thermostat or a possible air bubble in the cooling system that bled out. 220 on a hot day isn't overheating, BTW. It's warm, but won't hurt anything unless you're spitting out coolant.
 

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Maybe you should check the temps with a external thermometer to see if the gauge shows the correct temps all the time.
After I switch of my engine it always climbs up a little on the analog gauge (for example from 180 to 210) and as soon as the engine is switched on again and the water circulates and the fan starts it goes down to 185-190 within 5 seconds. I always thought this happens because as soon as there is no circulation in the water the temps increase a little because the engine parts are hotter than the water and it is no longer cooled down. No need to worry at all if it goes down quickly after starting the engine.
 

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Discussion Starter #4
timing

Rechecked timing. With parking brake set and car in gear, vacuum advance disconnected and idle at 600, she was showing 6 degrees of advance.(Cranked up easy at that spot and ran great, but not exactly a powerhouse). Would it run hotter at this setting? Initially I did have it set at twelve degrees, but after she ran awhile, it would tend to crank over hard. So now I've got it at ten before, and it idled 1/2 hour in gear at 180 degrees.(205 after shutdown). If you shut it off, then cranked it right back up, it would crank and fire up immediately, but if you waited 3-4 minutes, it would drag on the first revolution then fire up. Then immediately if you just cranked it right back up, it'd fire without fail every time. Is there a fine line between starting easy, but running hot, and running cool, but starting hard? The temp. does drop back to 180 after starting, but that annoying cranking deal leaves a lot to be desired! (new starter). Any tricks up yer sleeves? TNX.
 

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You have two things working against you: overly advanced iginiton timing and starter heat soak. Sounds like it wants to run at 12 initial, but 6 is stock specs. You can: retard the timing a hair, get a better starter (mini-starter), or install an ignition cut-off switch. The cut off switch will allow the engine to crank easily, and then you can flip it on and it will start right up. What's happening now is the spark is happening when the piston is on the way UP the cylinder, and that causes the piston to want to go back DOWN the cylinder, which is not a good thing on compression stroke. Me, I'd back the timing down a hair.
 

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Discussion Starter #6
timing

Thanks geeteeohguy, I really like that ignition cut off suggestion...seems to stand to reason that it would work like a charm. Just an interrupter on the run leg of the ignition switch, I presume? I like it! But I will pull the timing back some, but at 12 before, it runs like a bat out of hell. Does the engine run hotter when it's at the more advanced position, or the retarded position? Thanks again. G.
 

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Engine will run cooler the more advanced it is, generally. I ran my hidden ignition kill switch on the ign coil + wire circuit. You can use it as a temporary disable starting aid, and for peace of mind when you park your car. The switch needs to be in a non-obvious spot.
 

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Discussion Starter #8 (Edited)
timing

Nice!!!!! One more question. Do I need to re torque the intake and heads? Probably put 100 miles on her so far. Used the blue Fel-Pro gasket kit. Or do these not need a re torquing? Thanks. G.
 
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