I ran the break-in for about 20 minutes. It seemed to go ok but I have a strange observation. the paint on the new headers only burnt off 6 pipes. Cylinder 2 and 6 did not burn off the paint. I changed the plug wires and still no burning off the paint. Timing was fine and engine ran cool. Idle was able to be kept even.
Break in question . burned paint?
- Thread starter Kent mosby
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Once again, what are we working on here? And what kind of carburetor and intake manifold? You may want to go ahead and run a compression test, even though the plugs look like they're on the rich or cold side?
512 rb 175 compression in the non burnt cylinder. Carb. 750 holley. torker 2 manifold....
Pipes are not peeling paint on cylinder 2,6 and not as much on 4
I take it that the other cylinders are at nearly the same compression ratings? Are you running a carburetor spacer? The Torker II is little on the small side for a 512, it has been my experience most single plane intakes in this size range work better with a one inch thick open spacer to help with fuel distribution. With that many cubes, it may need more plenum volume. How much cam and static compression? Valvetrain? Also, what are your ignition setup and timing numbers? Finally, what plugs are you running?
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"Timing is fine" Where IS the timing set?
Timing was 36 at 2200 rpm with vacuum advance removed and capped. cam specs. 244/252 @ .050”, 282/290 adv, .516”/.537” lift(1.5:1 rocker), 112 sep, .016”/.018” lash . Compression is consistent. Static compression is 10.3. . Trickflow 240 heads with 440 source 1.5 ratio valves. Only running outer springs on the valves. Ignition setup for now is a ready to run distributor with coil. When I install in the car, I will be putting on a super sniper with hyperspark coil and distributor but I do not have the fuel pump to run that on the stand. Carb is HOLLEY 0-80508SA 750CFM ALUMINUM VACUUM SECONDARY . Plugs are autolite 3924.. I do have a Mr. Gasket carb spacer, aluminum that I can put in. I am going install the inner springs and reset the valve lash, insert the spacer and give it a go. I know that the cheap ready to run distributor and coil are not going to cut it for high rpms but I figured that it would be enough for 2000-3000 on a run stand. Also, I just remembered that we did not adjust the air/fuel mixture at all. We just ran it OOB. Any help is much appreciated.
Good information! What I have been reading on the Torker II 440, it's actually pretty good on a 440, and it does respond positively to a one inch spacer. It's still small on a 512 but there are worse manifolds you can use. More than likely, the out of the box carb jet settings are on the lean side and the engine may also positively respond to a few more degrees of timing. If you have an infrared thermometer, check the actual header tube temps. Are those the spark plugs that TFS recommends? Can you give us a close up of the business end? Is there a thermostat and what was the coolant temperature?
We put the inner springs in and adjusted the valves per the cam maker, ( oregon cams), .016 intake , .018 exhaust. Placed the 1 inch carb spacer. Since we are all broken in, I was trying to get the idle set. I was only able to get it down to 1200, without stalling, with 10-11 inches of "manifold" vacuum by adjusting the A/F mixture about 1/2 turn out more than the factory 1 1/4 turns. I hooked up the vacuum advance to the distributor and we had the advance at 36 with the canister connected to the ported vacuum at 1200 rpms. The motor stayed cool at 175* or so. 180 degree thermostat. Pipes were over 500 on 1,3,5,7, 8. But only 240-300 on 2 and 6. 400 or so on 4. Compression was at 170-175 on all cylinders. Oil pressure was at 55-65 psi
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The extra wires hanging were to see if the first set were defective. They are not hooked up
Similar to individual exhaust gas temperature readings on a dyno. It’s probably overkill knowing that the tune up is probably lean with an out of the box Holley tune, but also curious just how close the two unburned pipes are getting to the ones with paint burning off. The coolant temperature concerns me because the plugs don’t appear to be getting up to their self cleaning temperature, especially if the engine is running lean. Those are equivalent to an 11 heat range in a champion plug, those may be a little cool for an aluminum cylinder head.
Why would only 2 cylinders not be heating? Could it be ignition? What plugs would you recommend? That plug is the trick flow recommended one for that head
The coolant temperature needs to be up higher, but I am suspicious of a vacuum leak somewhere in the system.
You need the coolant temperature at close to 190 burn those plugs clean. They should be fine once you get the coolant temp over 185 degrees. But 512 cubic inches should tame that cam down a little more than that. Grab a propane torch and start checking for vacuum leaks.
I will do that tomorrow. Thanks @Garrett Ellison for all the help. I had to shut it down for the day.. I will post what I find.
I understand, your in a whole different category of engine, it’s the one most of us here want to build. I take it when you added the extra springs you rotated the engine to confirm that all the valves were opening and closing fully. I get really weary during break in about camshaft failure.
Yes we checked for valves opening and that the push rods were rotating by marking them with soap stone and turning the engine over. All pushrods rotated smoothly and uniformly. The engine has been running for about an hour total.
Great job and congratulations! One thing I have learned here is that those guys in Oregon really have their act together on the camshafts, I haven’t read anything but good results from their products.
twayne24365
Well-Known Member
Keep a good eye on those rockers, we had a set of them on a 440 with solid cam. The roller bearings in the rockers started to dig into the shafts.
twayne24365
Well-Known Member
They also needed clearanced for a 1.55 diameter spring, they hit the retainers. That was a 440 source head tho
Only thing I can think of is to recheck the valve adjustment.
Keep us posted as you are able, curious as to how it turns out...
I will but it will not be until next weekend.. I got a new thermostat. What spark plugs will give me a hotter range than the Autolite 3924's. There is not one in the same numbering system that is hotter, just colder in the 3923's. @RustyRatRod, we just redid that valve adjustment when we replaced the inner springs. I will also check for vacuum leaks. I think there is one between the intake and the heads. There were a couple backfires of flame through the carb and I can see some "smoke stain" looking for a better tem , but it escapes me at this time.
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