Carter/Eddie AFB question

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Newbomb Turk said:
I asked this before (I thought I did anyway)but didn’t you dyno your engine?

If so, where does peak torque begin and how far does it maintain peak torque?

Because 22-24 below peak torque is a lot. And I suspect you are at full timing during peak torque which is a power killer.
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Are you saying I should delay full advance until 4800 rpm ?
What are you referring to when you say “ 22-24 “ below peak torque ?
 
mbaird said:
View attachment 1716288363
Oops … wrong pull . Here is the best pull .
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IMO it’s going to be very difficult to get a curve that engine will really want.

Somehow you’d need to slow the curve down so that at peak torque you have 24-26 there and then get it to 33-34 by 6k’ish.

Yours is a case where a programmable ignition would be worth the money. Then it would be quicker and easier to get a curve in it.

Of course I’d want to do that on the dyno. I mean you can do it in the car but it’s not as easy.
 
Newbomb Turk said:
IMO it’s going to be very difficult to get a curve that engine will really want.

Somehow you’d need to slow the curve down so that at peak torque you have 24-26 there and then get it to 33-34 by 6k’ish.

Yours is a case where a programmable ignition would be worth the money. Then it would be quicker and easier to get a curve in it.

Of course I’d want to do that on the dyno. I mean you can do it in the car but it’s not as easy.
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I do have a programmable ignition .
Daytona Sensors CD-1

But I have never heard of a curve that slow . I will try it and see what happens .
 
mbaird said:
I do have a programmable ignition .
Daytona Sensors CD-1

But I have never heard of a curve that slow . I will try it and see what happens .
Click to expand...

I’m not familiar with that ignition but if it has a timing table you can make the curve whatever you want.
 
mbaird said:
One of the engineers from Crane started Daytona Sensors .
Very popular in high performance boats . Has a lot of cool features and is reported to be of superior build quality to MSD .

Welcome To Daytona Sensors™
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Ignition type and strength makes a BIG difference. Bruce stated he would ALWAYS make more power with the Crane when he would swap out other ignitions and coils. I saw it first hand when swapping out from the MSD.
 
mbaird said:
I do have a programmable ignition .
Daytona Sensors CD-1

But I have never heard of a curve that slow . I will try it and see what happens .
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Is this for a street machine where 4000 is like 65mph with an automatic in Second gear? and is this the usual shut down area?
I think @Newbomb Turk is talking about on the Dyno, where the last 1 degree might make 7 hp on a 360 (don't know about a stroker).
 
Hysteric said:
Get familiar.......
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Naw. If I’m going to do a programmable ignition it’s going to be the MSD 7831. I think that’s the part number.

It will do individual cylinder timing and if I’m going down the rabbit hole of programmable ignitions I’m going to the very bottom of it.

Edit: it's a 7531 MSD.
 
Last edited:
mbaird said:
One of the engineers from Crane started Daytona Sensors .
Very popular in high performance boats . Has a lot of cool features and is reported to be of superior build quality to MSD .

Welcome To Daytona Sensors™
Click to expand...


I’m going to look that up now. Seems like I looked into Daytona Sensors when MSD corn holed Mallory but that was a while back and I could be wrong about that.
 
AJ/FormS said:
If you can't get yours down that far I would suspect internal friction. In my case I had to take the engine down, add ring-gap and a tad more skirt clearance. Badaboom.
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OH MY, you didn't get it right the first time.
internal friction.:BangHead:
 
AJ/FormS said:
Is this for a street machine where 4000 is like 65mph with an automatic in Second gear? and is this the usual shut down area?
I think @Newbomb Turk is talking about on the Dyno, where the last 1 degree might make 7 hp on a 360 (don't know about a stroker).
Click to expand...
If your referring to my car it’s a 69 340 4sp Swinger with 3.91s . 4” Stroker , W2s , solid roller .
Day 3 car . Stock appearing .

2BE73B75-9770-4782-978E-7C6D25D7895B.jpeg
 
mbaird said:
I will adjust the VA can to start at around 11-12” and reconnect later .
I have reinstalled my 850 4150 for now .
The Carter was an exercise for the moment but I ran out of time to mess with it for now .

Its interesting how many mods there are for AFBs/AVS’s that most are unaware of . I wish there was a source for annular discharge boosters for them .
Edelbrock refuses to sell them individually.
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The Carburetor Shop; 651-770-3505.
 
Bewy said:
[1] The first thing to check is that the passages in the AFB base are covered by the gasket/manifold flange. If not covered, you will have a large air leak which would explain your some/all symptoms.
[2] Engine idling, remove the PCV & make sure it is pulled in. If not 'in' or vibrating it is adding varying amounts of air & playing havoc with idle air metering.
[3] The cheap [ & simple ] fix for [2]: get a 3/8" diam bolt & cut off a 3/8" length of it. Drill a 1/8" hole through it; push into the PCV hose. You now have a functional PCV.
[4] The ProCrap 850 probably had adjustable by pass air, & this carb may need it too.
[5] Not time for drilling holes....yet.
[6] Single plane, & a Victor, will provide less vacuum & exacerbate the problem.
[7] What are the cam specs & timing at idle? See below.

View attachment 1716287684
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Wow, 50 deg BTDC at idle can be optimal! I have sort of seen that several times. The Holley 1920 on my 1969 slant-six was quirky, always idling rough and wanting to die. It was happier with >20 deg advance at idle. If I tried to set to the book ~5 deg, then gave a little throttle the engine would race up in rpm which, giving more advance which it seemed to like. Shifting to "D" would bog it down, rpm dropping low where it lost advance and would often die trying to leave a stop light (bad for wifey). I had tried many things, rebuilding the carb myself, 2 store rebuilt ones, valve job (per mechanic). Finally after a whole new long block still wouldn't idle well, I tried a 4th carb and it idled like a kitten purring and no more bog leaving a stop sign. I suspect it was running lean with all the other carbs, both from wanting so much advance and because unscrewing the idle mixture didn't help much. So the carb can be the culprit, and hard to know what is going on inside, especially in those days without an O2 sensor.

Dealing with that last week with my 1964 slant w/ BBS carburetor. It wanted 35 deg advance to idle without dying, and still rough. Strangely, long ago when I bought the car, it idled so smooth you could hardly tell the engine was running. Since then I changed to an electric fuel pump and GM 8-pin HEI ignition. Installed an O2 sensor and meter, but it just shows full rich all the time. I'll approach it methodically. Bought a piston-stop to verify TDC mark, check fuel level in carb, rebuild carb, bought rebuilt Mopar e-distributor to replace new one (Chinese?), will drain and refresh the gas. I think the engine is fine since it ran so well before and still runs smooth when idling >1500 rpm.

The public thinks old engine controls were simpler to diagnose and repair. Not true. After a re-ring of my 1996 Plymouth 2.4L (fix endemic head gasket oil leak), it fired right up. As long as you get the camshaft marks aligned, there are no other adjustments. Spark is perfect from the crank-triggering and all settings in the engine controller software. As long as your engine is stock and good compression, it "should work". Easy to verify via O2 sensor plots via OBDII adapter. Not so with an after-market controller, since back to fussing with spark timing and O/F adjustments, though easier fussing via PC settings than mechanical adjustments in a carburetor and distributor, and auto-tuning software simplifies it.
 
Hysteric said:
1/10th of a degree I'm told is noticeable
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That cracks me up.................Maybe as to Power, on a dyno graph.
But we're NOT in the racing Forum, so I'm assuming this is in a streeter.
In which case, your only means of comparison is in a seat of the pants.
From my personal testing;
Not even three degrees are noticeable by seat of the pants,
until the tires stop spinning, and mine are still spinning until past the speed limit, anywhere in Manitoba, Canada.

Now, if your talking 3 degrees at stall-speed, sure but
Firstly, your stall speed in a streeter is not usually 3500, so good luck as to a repeatable timing number.
But again, it only counts if the tires ain't spinning, which means most of us 360 guys are gonna be on the Primaries, and not even all the way open.
I can only Imagine a stroker.
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Or maybe it's just myazz that can't feel the difference.
In any case, my maximum Power-Timing at any moment in time, is somewhere between 32 and 34, as adjusted by my dash-mounted, dial-back, Timing Module , because;
I cannot, by seat of the pants, feel any difference from 32 to 36, and the car goes 93 in the Eighth, with the Power-Timing set at that 32/34, so why would I even care about a 1/10 of a degree?
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You might ask, why do I have a 2 degree timing window?
Well cuz the dial-back module is none-too repeatable, and mine is NOT set in the center, but rather about 40% of scale and there are no graduations. I use that tool to augment my cruise-timing, every time I leave home. When I get to my destination, I reset the knob to "somewhere in the vicinity" of 40% which is probably 32 to 34 degrees on the timing light, and that's close enough.
I mean, I suppose if you had a 318 with like a 288* cam and cylinder pressure under 100psi, I suppose it could matter, lol.
But my 367 has a preponderance of torque, and a preponderance of torque multiplication, which translates to a preponderance of tirespin, so she don't care ............ about 3 or 4 degrees of timing retard, much less 1/10 of a degree..

Now, I'm not bragging on my specific engine.
I'm sure every 360 out there has the potential to be just like this.
My engine is NOTHING SPECIAL, except maybe for the high cylinder pressure and life-long diet of 87E10; lol; , but most of what she does is due to having the right gear at the right time, and the potential to still be pulling long after the Power peaks.

The thing that does set my combo apart is the GVod being used as a splitter. While most of you 93 mph streeters with automatics and 3.23s are just thinking of shifting into third, at 93mph; I'm already at the top of my FOURTH gear-ratio selection, which was;
a faster-than-lightning electric shift, rpm drops to .78=1300rpm
followed by a straight back 1-2 manual shift, rpm drops to .80=1200rpm
followed by another electric shift; again to .78=1300 .
and, I still have,
Third, Fourth, and four-Over left.
After the traps, still being in od, I just shifted from Second to Fourth, where 93 is 3200, and let compression braking drag my speed down.
It works almost as good on city streets, except I only need one gear most of the time; could be Second; 50mph =4300, or could be First-over; 50=5300
Now, that's worth a brag, on the GVod!
 
BillGrissom said:
runs smooth when idling >1500 rpm.
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I never had a slanty that wouldn't idle at 500 in gear, and 450 without load.
But, you know, with just three shots per revolution, the engine, at low idle, has a naturally unsmooth and characteristic cadence.
This cadence is completely unrelated to carburation and or Idle-timing; it's always there at 450/500 rpm. But, standing at the tailpipe, I like the thoop-thoop-thoop sound. Oh sure the engine is jumping around on the mounts some, which is natural with heavy pistons flying around on a 4.125 stroke, just 3 pulses per revolution on the Flywheel; and the tailpipe is dancing on it's rubberized hanger; but that thooping business, floats my boat. I mean 450 rpm @3 shots per Revolution is 22.5 shots per second, you can't count that fast, but you almost think you can, lol.
 
AJ/FormS said:
That cracks me up.................Maybe as to Power, on a dyno graph.
Click to expand...
1/10 of a degree change was stated to be noticeable from a seat of the pants perspective.
 
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