360 LA installing Promaxx Aluminum heads

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TT5.9mag said:
Where is your o2 sensor located? And is the exhaust tighter than a dolphins ***? Like zero leaks?
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Sensor is just down from the shorty collector as the exhaust straightens out. You can see the bung in the photo below from when I installed the exhaust. Exhaust is tight.

Reading manual for sensor... says should have re-calibrated after 3 months... I'm a bit overdue.

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That’s not terrible placement. Within 18” of the collector is ideal and I think you’re there. But you are only reading one bank and have a dual plane intake so cylinder to cylinder distribution may be at fault here. Basically what I’m getting at is don’t trust the sensor for gospel. Give the engine what it wants and rely more heavily on plug reading. Speaking of that can we see a plug?
 
TT5.9mag said:
That’s not terrible placement. Within 18” of the collector is ideal and I think you’re there. But you are only reading one bank and have a dual plane intake so cylinder to cylinder distribution may be at fault here. Basically what I’m getting at is don’t trust the sensor for gospel. Give the engine what it wants and rely more heavily on plug reading. Speaking of that can we see a plug?
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I'll pull a few tomorrow.
 
FWIW, if it runs and drives better a little richer than when it’s leaner, then leave it. On a technical spec, it should be a certain way. It may not be what the engine likes best.
 
Slow day.. spent the morning cleaning up the garage. You know how it gets after a major operation. Anyway I did get around to pulling a plug, this is #1.
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If I had to venture a guess that black smut is leftover from when it was running much fatter.
 
Probably so as when the engine runs leaner it’s the porcelain that cleans up not the rest, ground strap excluded.
when you look down into the deep part of the plug, what colors are there?
 
Garage clean up…. Good have t done that in a while.
Not a bad idea, might just get on that now. Crank up a few tunes and out some **** away… hummm, sounds like a good idea since it’s close to half a bazillion degrees outside and working on the truck without shade is dangerous for me.
 
rumblefish360 said:
Probably so as when the engine runs leaner it’s the porcelain that cleans up not the rest, ground strap excluded.
when you look down into the deep part of the plug, what colors are there?
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Could not get a good shot of the porcelain down deep.. but it was white as far as I could see.

Looking at the ground strap I might have a bit too much timing in it. Will check and adjust again today. IIRC that coloration should not go all the way to the body of the plug.
 
Just checking. According to the plug your lean. Re-calibrate the 02’s. Perhaps, IDK for sure, but the placement of the 02’s might be a little far away from ideal. I use headers and there placed right in the collector, not the reducer. I also install the full exhaust system that I’ll use since it plays a big role in how the carb see’s the signal and operates.
 
rumblefish360 said:
Just checking. According to the plug your lean. Re-calibrate the 02’s. Perhaps, IDK for sure, but the placement of the 02’s might be a little far away from ideal. I use headers and there placed right in the collector, not the reducer. I also install the full exhaust system that I’ll use since it plays a big role in how the carb see’s the signal and operates.
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I'm of the same mind.. looks lean to me. I'm going to get the vac gauge and timing light on it again later today... we'll see what vac and timing light say vs. the o2 sensor before the re-calibrate.
 
Looks one or two (maybe) heat ranges too hot, timing might be a little high, I’d guess 36-37 degrees and rich at idle. Can’t tell WOT without cutting off the shell.
 
74Scooter said:
Slow day.. spent the morning cleaning up the garage. You know how it gets after a major operation. Anyway I did get around to pulling a plug, this is #1.
View attachment 1715964241

If I had to venture a guess that black smut is leftover from when it was running much fatter.
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Do NOT touch it. That’s what a pump gas plug SHOULD look like.

The only thing we can’t see is WOT. Cut the shell off and see where you are. Then screw in a new plug and make a clean cut pull at WOT and do it again. You can’t the fuel ring to be .080-.100 wide.
 
Rat Bastid said:
Do NOT touch it. That’s what a pump gas plug SHOULD look like.

The only thing we can’t see is WOT. Cut the shell off and see where you are. Then screw in a new plug and make a clean cut pull at WOT and do it again. You can’t the fuel ring to be .080-.100 wide.
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You don’t think that plug might be a little hot?
 
^^^ I picked up a set of the next step cooler plugs... NGK BKR7E. I'll give them a try tomorrow and probably try taking a couple of degrees of timing out of it as the color on that ground strap is a bit close to the base.

Aside from that are we on concurrence that the AFR (for everything other than WOT) is likely good where it is at?
 
TT5.9mag said:
You don’t think that plug might be a little hot?
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Without being able to put my eyes on it, I don’t think so. I can’t tell what brand of plug it is either.

I can’t see any cement boil and all the edges of the ground wire and center electrode still look pretty sharp.

BUT…that’s what I can see in a picture. The OP is close enough on his tune up that he needs to get the shell off and look at his fuel ring and get a real good magnifier on the sharp edges of things and start looking for signs of overheating.

It’s so hard to see any detail in pictures that it could be a range too hot.

But he is very close on his tune up either way. From this point he is just refining what he’s got and he doesn’t need any big changes anywhere except maybe WOT. And maybe not even there because we can’t see that.
 
74Scooter said:
^^^ I picked up a set of the next step cooler plugs... NGK BKR7E. I'll give them a try tomorrow and probably try taking a couple of degrees of timing out of it as the color on that ground strap is a bit close to the base.

Aside from that are we on concurrence that the AFR (for everything other than WOT) is likely good where it is at?
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Ok, just saw this after I made my last post.

Your heat range is fine. That’s an NGK plug. If it was a Champion or Autolite I’d say it’s too hot. NGK has their plugs run hotter than other brands.

Don’t take any timing out. This is pump gas. Not race fuel. You want the burn line almost to the shell. You have it right where it should be.

Pump gas doesn’t read like race gas and neither of those read like methanol.

You are real close. You don’t need a timing change. That’s what it SHOULD look like. Even the carbon on the shell above the threads. That’s pump gas. It’s what you get.
 
74Scooter said:
Slow day.. spent the morning cleaning up the garage. You know how it gets after a major operation. Anyway I did get around to pulling a plug, this is #1.
View attachment 1715964241

If I had to venture a guess that black smut is leftover from when it was running much fatter.
Click to expand...

You need to wrap the plug in the palm of your hand. Cant tell what colour that is on the ground strap but the porcelain looks very white then that tells you its lean.

Tune to the colour of your plugs not an AFR number. Go up a jet size and see what it looks like then.
 
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74Scooter said:
^^^ I picked up a set of the next step cooler plugs... NGK BKR7E. I'll give them a try tomorrow and probably try taking a couple of degrees of timing out of it as the color on that ground strap is a bit close to the base.

Aside from that are we on concurrence that the AFR (for everything other than WOT) is likely good where it is at?
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I agree with @Rat Bastid that you are very close. I would like to see the fuel ring and a limited idle wot pull on new plugs before making any final judgment, but if it were mine, (and I run NGK plugs), I wouldn’t pull a couple of degrees. I’d pull one degree of timing because it’s a street car, race car I wouldn’t and I’d watch em more closely. And I’d go one step colder because I see color pretty far down the threads. But that’s a good looking plug for a carbureted street car.
 
I also agree with rat Bastard but still advise a 1 step richer mixture to see what happens as well as the OP said the 02’s may not be calibrated. I mentioned looking down into the plug to see what’s going on. I also think the porcelain is very white. My disclaimer, I never worked with NGK’s.

I figured the richer change could/would show on the plug and the worst case scenario would be to go back to the last step. Such is the way of tuning and many other things about cars.
Hysteric said:
You need to wrap the plug in the palm of your hand. Cant tell what colour that is on the ground strap but the porcelain looks very white then that tells you its lean.

Tune to the colour of your plugs not an AFR number. Go up a jet size and see what it looks like then.
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Agreed. The AF ratio via the 02 is a great way to start the process and get you there quickly. It is not the end all. Also hence why I asked if there is a drag track.

IMO, he could just leave it alone and it’ll be good. If he can get great, even better. Considering it’s summer time, when I’m tuning up a ride, if it is a slight off on the rich side, winter will take care of the rest with more cold dense air.
 
Went ahead and swapped out the plugs today to the 1 step cooler NGK BKR7E. Photos of the BKR6E below.. I snapped the porcelain on #4 taking it out... dunno how. I don't think I've ever done that before. So now I have my victim to cut open later. If the porcelain tip on #1 looks a bit darker its because I hit the threads with a brass brush and dirtied it.

Verified timing at 11-12 initial. Had some issues with my Snap on timing light so I could not verify total mechanical advance. IIRC that puts me at 35-36 total.
Vacuum sitting steady at 10-11 inches idle.
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So the cooler plugs are in and she's hummin'. Tooled it around town for about an hour mixed driving. Got on the highway uphill and leaned into the throttle just a lil bit.. looked down at the spedo and I'm at 105. :steering:

Readout on the AFR is a hair leaner than last night. Could just be time of day.. about 20 degrees cooler today. Need more saddle time to collect data. Seat of pantelones says this rig is dialed in pretty nice. No stumble and power seems really good through the band. I'm really tempted to stand pat as-is. Lots of nice cars on the streets.. Hot August Nights started yesterday and I wanna drive... lol.

Group shot:
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2-8
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1-7
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You see the spots on 6 and 8 and maybe a bit on 4?? Those are from little vortices forming right by the plug. Darin Morgan has some good videos on that. Worth watching those if you have the time.
 
Rat Bastid said:
You see the spots on 6 and 8 and maybe a bit on 4?? Those are from little vortices forming right by the plug. Darin Morgan has some good videos on that. Worth watching those if you have the time.
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Does it have something to do with the direction the electrode is pointing in the head?
 
74Scooter said:
Does it have something to do with the direction the electrode is pointing in the head?
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No, it’s plug location and things like that. I’ve changed a valve job before and stopped it but that to be luck. That wasn’t the plan. I just hated the valve job that was on the heads when they came into the shop. That was just a byproduct of fixing the valve job. Only explanation I can give on that.
 
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