Rat Bastid
Dunamis Metron
You don’t need to unhook that one to charge the battery.
340 Chugging instead of Reving
- Thread starter 1969GTS340
- Start date
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You don’t need to unhook that one to charge the battery.
It sounds like the focus is back on the mechanical side of things again then. I should have time this week to validate.
Is it possible it's firing when the valves are off the seat.
as in valves not closing totally.
as in valves not closing totally.
Reading back through, I don't see mention of valve springs. New? Used? Shitty bad new ones?
This is a brand new build, the engine was broke in with only the outer springs then inserted inner springs after 20 - 30 min at 1800-2000 rpms
Yes that is possible. I am planning g a leakdown when I can coordinate the equipment with a buddy. I did verify lift of each valve and cam lob with a dial indicator. Once peak lift was reached, I walked the valve back down.to zero while looking for a sticky spot on the indicator which may indicate the valve was sticking. None were found during that test.
I agree but don't have a set up available.
That's interesting. If I understand correctly, this would provide a site window to inspect the alignment of the rotor to the cap #1 firing position? If it was found to be off, how would it be corrected?
Here's a question for the ignition guys. My understanding is that the reluctor blade should be lined up with the center of the pickup when firing? With my timing set at 32*, the blade on the reluctor is full blade width away from the pickup. Should I adjust the pickup to center blade and regap at .008 ?
Might be difficult to see in this pic (attached), The rotor is between 8 and 1, I'd say closer to 1, which may be correct at 32btdc. If I rotate the engine to bring the reluctor dead on, the rotor is darn close to dead on and the timing mark is at TDC. So basically, as I advance the timing, both rotor and coil off shift the same amount. Since my rotor is not adjustable, I just tried moving the pickup. It's obvious that it doesn't move in all directions like points. There is virtually nothing to gain in trying to move the pickup.
Edit... I am adding a second pic, trying to show where the rotor is in relation to my TDC mark on the back of the intake below.
TT5.9mag
Two atmospheres are better than one
Ok try this, with the distributor advance locked at 32, MAKE the pole on the reluctor line up with the pickup dead nuts on center AND the rotor line up dead nuts on center on the number one terminal in the cap. You might have to remove the distributor to do this. Do NOT line them up at TDC put your balancer at 32 degrees btdc
If the reluctor is lined up and the rotor is pointing to #1 at TDC, it should line up when distributor is twisted to 32btdc
in firing phase.
It should be pretty easy to figure out.
in firing phase.
It should be pretty easy to figure out.
That is what I tried to describe that I did above. With the dist locked and engine timed at 32btdc. I pulled the cap and turned the engine over by hand until I got to 32btdc. The pics above show the misalignment of the pole / pickup. and the rotor was before the #1 button on the cap.
I'm learning this as I go but it seems to me that the location of the rotor is correct when set to 32 btdc. I didn't calculate the radius of the cap x 3.14 bla bla bla.... but it's close. In addition, when the rotor is at 32* shouldn't the reluctor pole be dead nuts over the pickup/firing?
Compression test complete.
1. 149
2. 149
3. 149
4. 148
5. 149
6. 151
7. 148
8. 149
The new plugs (30 minutes old) came out wet and black.
When I turned the engine over to do the compression test, gas was spaying out the remaining open plug holes onto the tops of the fenders.
I'm taking a shot in the dark here but, with the rotor and pickup being out of phase, isn't this another indication the phase needs ro be corrected?
1. 149
2. 149
3. 149
4. 148
5. 149
6. 151
7. 148
8. 149
The new plugs (30 minutes old) came out wet and black.
When I turned the engine over to do the compression test, gas was spaying out the remaining open plug holes onto the tops of the fenders.
I'm taking a shot in the dark here but, with the rotor and pickup being out of phase, isn't this another indication the phase needs ro be corrected?
Ever look down the carb while running at the rpm’s you say is starts chugging? Tried lowering the fuel pressure a little and run it?
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I've ran pressures from 7 down to 4.5 while running the engine. It didn't make a change in performance. I have not looked down the carb when it starts to chug or pop out the exhaust. I did change carbs to one from a.running car with no change. I can say there is a lot of unburned fuel.
I’d run it to warm the engine up a little then turn off the pump and then bring up the revs to (where you had the chugging) and see what it does, before the bowls empty.
Phreakish
Well-Known Member
I think you're onto something with the reluctor.
I'm not familiar with that distributor, but is it possible the pickup wiring is backwards? I seem to remember if it's flipped, you'll get more "advanced" spark when looking at the rotor and reluctor relationships to the cap and pickup. The spark will also be shitty - but no idea if that applies to your Dist?
Typically, a magnetic pickup should be wired in the direction that results in the least advance (most retard).
Figured I'd mention it, if it applies.
I'm not familiar with that distributor, but is it possible the pickup wiring is backwards? I seem to remember if it's flipped, you'll get more "advanced" spark when looking at the rotor and reluctor relationships to the cap and pickup. The spark will also be shitty - but no idea if that applies to your Dist?
Typically, a magnetic pickup should be wired in the direction that results in the least advance (most retard).
Figured I'd mention it, if it applies.
MOPAROFFICIAL
Oogliboogli
Adjust the total/full advance timing down to 28 degrees... then test drive it.
It may only take 6 to 10 degrees mech advance with that head, say .. if you're running a higher initial like 20 degrees btw @idle
Do a cranking compression test 'carb open' and let us know if you can.
Also ..it only needs about 5 psi. 7psi is testing the needle n seats imo. Thanks for considering this board for help, you're in good hands.
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