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Discussion Starter #1
So, it is just like the title says. So here is the particulars.

327 .030 over
10.25 to 1
461 heads ported
2.02 intake
1.60 Exhaust
Victor Jr single plane intake
Isky Solid Cam
244 / 248 @ .050
560 /570 lift with 1.6 rockers
Demon 850 DP (yes it's a little big, but on loan)
New BHJ Balancer
Speedway HEI

11 inches of vacuum.

After breaking in the cam, and just enough carb adjustment to get it running, trying to tune it, we discovered 55 degrees initial timing. When trying to set the timing lower than that, it ran like crap, it really wants 55 degrees. Now, we verified TDC on the balancer and timing tab, it looks right. It does not kick back or drag when cranking. It starts like its at 12 degrees.

I set up the cam straight up and timing marks should be right on dot to dot.

I have no idea how this is possibly running with 55 initial. Nothing seems wrong. So give us some suggestions on what to check. I don't want to pull the front of the motor apart to double check the cam timing marks, but that's where I am. Thinking possibly checking cranking pressure based on a dynamic compression calculator estimate. Or am I reaching. I am looking for some direction.

Any help is really appreciated.
 

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Ok. so as much as Duke wants it to run like crap so I don't whoop him and he has to put more money in his 64. Any help is greatly appreciated.
 

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Sounds to me like you have a 350 balancer. The key slot is in a completely different location relative to the timing mark. This changed in '69.
 

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Discussion Starter #4
We can check the balancer PN, but we used a borescope to verify TDC was on the mark.
 

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Discussion Starter #6
Thanks, we may have to degree it, we had planned to, but I couldn't find part of my degree wheel kit. I am hoping to avoid that.
 

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Sounds like your 327 has a small journal crank. If so, the orig balancer's keyway is pretty much in line with the balancer's timing mark (and the location of the tab on the cover is different as well).
A 350 balancer and all aftermarket balancers, have the timing mark at about 11 degrees (from memory) in advance of the keyway.
True TDC means nothing if your parts are incompatible and you have not remarked your balancer.
 

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Sounds like your 327 has a small journal crank. If so, the orig balancer's keyway is pretty much in line with the balancer's timing mark (and the location of the tab on the cover is different as well).
A 350 balancer and all aftermarket balancers, have the timing mark at about 11 degrees (from memory) in advance of the keyway.
True TDC means nothing if your parts are incompatible and you have not remarked your balancer.
Likely what it is.
 

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Discussion Starter #9
Wow, looks like I am going some research tomorrow. Yes it is a small journal 327, I sold him that crank and block 20 years ago.

So I understand the balancer may be wrong, but was the timing pointer in the same location on a small journal 327 and a 350? Just so if we end up replacing the balancer we are not still off.

Thanks for the help!

I promise I won't tune his car well enough to beat me. "Sorry man, I just can't seem to get that stumble out!" :D
 

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The easiest way would be to use an early balancer IF you still have the early cover with the corresponding correct tab placement.
Assuming you can't easily source an old balancer I'd use a piston stop and determine true TDC then, use an adjustable pointer to line up with the mark on the new balancer. Put on a timing tape and you will be good to go....
 

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It wont matter which style balancer you are running as long as the timing pointer matches the balancer you have. You need to use a degree wheel to verify true TDC and then make sure the pointer you have lines up exactally with the balancer. If not an adjustable pointer would work well here. Then use a quality (no cheap chineese stuff) dial back light to properly time it. You are timing it with the vacuum advance unhooked and the port on the carb plugged right? Cam timing wont affect ignition timing. If cam timing is off, you will have other issues like popping out the carb or pipes.

One thing that could ba an issue is your intake/carb choice. You have old heads with mediocre air flow capabilities, and a decent sized cam. A dual plane intake would run better, as would a properly sized carb. With that big carb and open intake, your signal through the venture's is pretty weak. You may be sucking in more fuel in droplet form than a fine atomized mist. Droplets of fuel are much harder to burn and burn more slowly. This will require more spark lead time as well. I think you have a few issues working against you right now.
 

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I ran into this exact same problem several years ago with an 11:1, 327, blueprinted engine.
This engine was professionally built by a race-engine builder, and it had a really nasty Crane solid lifter cam (dyno 398 hp/ 395 lb ft.) per the builder's recomendation!
Problem was it was terrible to drive on the street! (couldn't let the clutch out under 1500 rpm, no idle below 1000) but what an animal it was!!!
Back to him for a cam change to another Crane solid which was a step milder. Second Crane cam, still not street friendly...
I've done a lot of engine work over the years, and am no novice to cam swaps, but I figured "he spec'ed it out, he can make it streetable!"
This time "I" swapped to Comp Cams 69 Z28, 327/365, 70 LT1 retro replacement solid lifter cam, and changed it in the car.
I did not degree it, feeling that it degreed in spot-on for the 1st, 2 Crane cams, it should be perfect for the new Comp cam. (straight-up)
Hand advancing the distributor (with my calabrated eyeball), with about 20 degrees advance, the engine couldn't get it's act together enough to start. I gave it more and more initial advance and she came to life as I gave it it's 20 minutes above 2000rpm, cam break-it.
Checking my Snap-on dial back light, I couldn't find the mark???
Shut it off for a cool-down and leak inspection, and restarted it.
I could not get it to idle with less then 40 degrees initial timimg???
Installed a piston stop, checked balancer TDC=dead-on.
Pulled balancer, water pump and timing cover.
0's on timing chain perfectly aligned (not 4* advanced or retarded)
Degreed cam to find it 7 degrees retarded per cam card!
I bought an adjustable timing set with 9 (I think) keyways from Summit and installed it. Degreeing it "strait-up per the cam card", not the on-line info which is different, I reassembled and fired it up.
I couldn't tell which was louder at the time, my heart beating or the car's exhaust but I set the dial-back for my 17* initial and squeezed the light's trigger. The light was flashing 2* off TDC (whew!!!)
I adjusted the initial to 17* at idle, brought the rpm's 2500-2800 while dialing the light's adjustment back with my teeth...
17* initial, 38* total...
Adjust the idle mixtures, the idle, connect up the vacuum advance, close the hood and take it for a scoot around the bucolic neighborhood.
Still runs real strong and has a healthy burble from the exhaust @ a nice 800 rpm idle, and doesn't require 3 feet to stop at a stop sign!
Lesson learned... Always degree-in a cam by the cam card only!
 

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Dialing in the cam

That's great advice Steve G. I found on any aftermarket cam no matter where the index marks are you need to dial it in. The OEM stuff is usually dead on but check with a dial anyway.
 

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Discussion Starter #14
Here are some comments and more questions.

Steve, thanks you, I had the conversation about single plane and that giant carb for the street till I was blue in he face, not my car, I lost that battle.

This is a super budget build, we both have younger kids and get the budget our wives allow. So the 850 DP in on loan from another buddy, e plan was to give him my 670 when I went EFI, but we got his car running about a year faster than anticipated. So a smaller craigslist carb might be the answer as far as it running like crap.

The balancer Mark we confirmed via borescope, though we can do a piston stop. We are on the mark plus or minus 2 degrees, so if TDC is correct, does it matter if it is not e correct one? This issue is TDC.

I am attaching the cam card which if I reading this right says 0 advance ground in.

We are not checking base with the can hooked up.

Now if it is actually needing 55 degrees due to the combo, maybe I'll pop my carb off and see what it does with a stronger Signal.

So after we confirm which balancer though if TDC is right not sure it matters, what should be my next step.? Swap carbs and see if it wants less timing?

Or pull it apart and degree the cam?

As always I appreciate everyone's help.
 

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I doubt that it has 55 degrees. I would be really surprised if it would crank over with more than around 35 degrees of initial timing. Other issues, carb, and intake manifold will not cause it to need 55 degrees of timing.... besides at 55 degrees it WILL detonate.
 

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Discussion Starter #16
Ignition Module

BHJ just got back to Sparky and they said if TDC matches the pointer we are good. Is there any chance the ignition module is bad? I guess that still does not explain the 55 degrees. I think I will loan him my timing light and see what that shows. I am still of the mindset no way it's actually at 55.
 

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As said the TDC mark on a 68 and earlier balancer is in line with the keyway. On a 69 and later balancer it's 10° CCW from the keyway. If you use the 68 and earlier timing tab, you'll indicate 10° more ignition advance than you really have.

There is also a fairly rare 350 balancer that has the TDC mark 30° CCW from the keyway.

I do not trust any dial back timing light except for the really high end ones like Snap On. A timing tape works well in place of a degreed balancer and is really cheap.

Cam timing does NOT affect ignition timing mechanically. That said with that big cam you'll need to run a lot of timing at low speeds.

A borescope can only be trusted to within maybe +/-5° on a good day. Use a piston stop or dial indicator.
 

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Discussion Starter #18
I think I am slated to go back over to Sparky's this weekend to see what we can find out. I will take my timing light and see if I can find my piston stop (I think it's hiding with the bushings for my degree wheel). I am also going to check that the vacuum and mechanical advance are not stuck. I was thinking even if it is the wrong balancer, I would still only be off 11 degrees, which still has us well over 40 initial. We will see what we can come up with. If I know Sparky, he won't lose any sleep over it, if it runs well, it's on to the next project. I will report back either way.
 

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I just noticed that you are using a Speedway HEI.
I suggest removing the cap and confirming the the distributor's centerplate is installed correctly.

Below is a diagram for the correct orientation of the weights and centerplate for a clockwise rotating engine.

Notice that the pointy part of the weights rest on the rounded part of the centerplate (Springs were removed for photography).

If the centerplate is installed upside-down, the weights will have a "sloppy" fit against the centerplate (even with the return springs installed) and could advance the timing at idle due to the centrifugal force.
I had a similar experience with a Pertronix HEI a couple years ago. I had a very high/erratic initial timing at idle due to my centerplate being installed upside-down from the factory. Once I flipped the centerplate, all of my "mysterious" timing issues were solved.

I would also check the timing light you are using on an other engine with a "Known" initial timing number to check the accuracy of your timing light.
 

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11 inches of vacuum is low if the cam is mild. that said, I would want to do a test first, to confirm or deny issues from the cam being off a tooth retarded.

Do a full engine compression test, all plugs out, throttle wide open. Extremely low readings will indicate the intake valve is closing way too late, cam retarded a tooth. This will give low vacuum readings, love extremely high timing numbers, have bad low end power, fair to good top end power.

Doing this will get the test done, and either show a problem, or not.

From the picture, the vacuum advance does not have any degrees stop in place, and being that way, is probably capable of making 25 to 30 degrees of timing, if the vacuum is enough to run the pull pin through its full travel.

I would want to see just how many degrees the initial is, with the vac adv disconnected, then, add the advance to full manifold vacuum, and see how many degrees comes up from it. To a point, the more IDLE degrees, the better the idle vacuum reading should get to, but, there is a reasonable limit of IDLE timing, 22 to 24 degrees, no more. Example: 14 INITIAL, add 10 by vacuum advance on full manifold vacuum, IDLE, 24.

A simple stop can be affixed to the vacuum advance to get to the right idle timing number.
 
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