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timing mark way off

ugly74

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Joined
Apr 17, 2006
Messages
2,847
I'm workin on a 351 cleveland ('71, 2v heads) I put together for my 74.

my specific question is:
what can cause the timing marks on the balancer to be off? in order to run, the initial timing needs to be so far advanced that when using a light, the marks can just barely be seen coming around the balancer on the left.
here's what I know for sure...
-TDC on the balancer is true TDC on the #1 piston.
-the timing gear marks are lined up perfectly.
-the valvetrain comes together with the correct preload (needed to shim under a couple of the fulcrums to reduce preload)
-compression is excellent, with practically zero variation between cylinders

so why does it need to be so freakin advanced to run?

please help...I'm about to yank this thing and reuse the 302 I had
 

Steve83

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Jul 16, 2003
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Loc.
Memphis, TN, USA, Earth, Milky Way
Some timing lights have a built-in advance, so try another light for comparison. Also, make sure the dist. cap is installed properly. Those with spring hooks can sometimes be installed out-of-place, which would throw the timing off. And timing pointers changed over the years, so make sure you're using the right one. Most 300ci/4.9Ls have 2; one cast into the timing cover, and a steel one bolted on. Maybe something similar is happening to you.
 

gearida

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Jun 8, 2007
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Loc.
Newburgh, IN
How far advanced is it? What are you running as a total advance, when the distributor adds timing? I have tuned vehicles (race cars) at total advance usually around 35º, or as much as 40º. Keeping it on the street I would not recommend that high however.
 

70_Steve

Old Guy
Joined
Dec 13, 2002
Messages
8,317
The first thing I'd do, if you haven't done this already, is verify that when the engine is at TDC on the compression stroke, the timing pointer is pointing at 0° on the balancer.
 

turbotim2

____________
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Jun 26, 2003
Messages
1,954
I have heard that sometimes old balancers can actually loosen somehow from the center and indicate wrong timing.
 

broncnaz

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May 22, 2003
Messages
24,341
Dist cap put on wrong wont make the timing marks change. Just means you have to turn the dist more to get it timed. it should still read the marks on the balancer correctly once the dist has been turned far enough.

Double check make sure your #1 wire is the #1 wire. How is your vacuum advance hooked up? Is it single or dual advance? How does it run?
I'd also double check both the balancer and the timing pointer make sure they are correct for the application although if they line up at TDC they should be fine but a loose outer ring on the balancer could only be showing up when the engine is rotating.
While probably not your issue just to be sure. Also double check that you are checking everything off the #1 cylinder ie TDC and timing. (passenger side front cylinder)
While it shouldnt be that big of a issue variances in components can throw the timing off crank key way could be a little off, The cam ground a little off, the gears a little off it can all add up.
 

badmuttstang

redneck grease monkey
Joined
Oct 25, 2009
Messages
2,807
The balancer thing where the center comes lose is the polymer ring deteriorates to the point where the outer ring spins it could be the problem but if the timing is off that far the balancer would just about fall apart. I have heard that if you bolt up the wrong year balancer the timing marks will not line up with the pointer so make certain you have the right balancer and timing pointer.
 
OP
OP
ugly74

ugly74

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Apr 17, 2006
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distributor cap is on correctly, the outer ring of the balancer is on tight and true. I am checking the #1 cylinder, and the pointer is the correct pointer for that engine.
when the engine has no load (park or neutral) it fires right up, idles right away with no babysitting necessary, revs quickly with no hesitation. sounds bitchin (no pipes on it yet)

put it in gear though, and it runs like a champ up to about 3000k rpm...then starts misfiring, spittin and sputtering, power takes a serious dive, and just really doesn't wanna run at all. with or without the vac hooked up to the distributor. it is a single line vac advance, hooked up to the carb above the throttle plates.
I tried two different carbs (a 600 holley, and a 750 holley) and it ran the same with both. it had an older Accel dual point distributor...so I changed that to a Duraspark II setup. zero difference!

I'm guessing that the initial timing is around 30*, just to run. it's so far off the mark I just can't tell for sure. if I retard it at all, it starts to really bog down the idle, and it almost has a tractor-ish note to the exhaust.
I can't remember the exact numbers off hand...but I used a degree wheel and verified that the valve events are where they should be.
the lift is .508 intake and exhaust, and has kindof a long duration for a truck (originally bought for a mustang), so I retarded it 4*.
that's all the useful info I can think of...
 

Viperwolf1

Contributor
electron whisperer
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Aug 23, 2007
Messages
24,312
the lift is .508 intake and exhaust, and has kindof a long duration for a truck (originally bought for a mustang), so I retarded it 4*.

That's your problem. If you wanted to increase the low end torque you should have advanced the cam, or used a better cam.
 

bmc69

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Jun 11, 2004
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That's your problem. If you wanted to increase the low end torque you should have advanced the cam, or used a better cam.

woah nelly!..You called that right, Viper.You never, ever do that. I rarely ever run them straight up even..the .550 lift 284 duration cam in my 408C is advanced a full 4 degrees in front of cam card specs. Pulls like a mule. Base timing is 12 degrees..because of the stupid compresion I'm running I have max limited to only 24 all in.
 

bmc69

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I have heard that if you bolt up the wrong year balancer the timing marks will not line up with the pointer so make certain you have the right balancer and timing pointer.

Good advice..for Windsors. The Clevelands do not have all those variables..the balancers interchange and the pointer is stamped steel and bolts to only two bolts on the stamped steel timing cover.
 

broncnaz

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May 22, 2003
Messages
24,341
Yeah the windsor balancers fit clevelands so if the wrong one is on there the timing marks could be goofy.. But it sounds like theres other issues at work here.
I'm thinking vacuum leak or theres a valve train issue valves to tight, lifters pumping up, Wrong valve springs for that cam. Really need the duration numbers lift doesnt mean much.
Didnt the 2 barrel C heads have some valve issues like spring retainers and weak springs which commonly break? Might want to recheck that valve train.
 

bmc69

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But it sounds like theres other issues at work here.

uh no..none. A 'C' seldom runs happy with good vacum when an aftermakrket cam is set up with zero offset. I never (as in 40-50 C builds over 30 years definitiion of 'never') run anything but the most radical race builds anything less than 2 degrees advanced over stock specs..and more typically and most always 4 degrees advanced. Custom grinds that take that in to account..excepted.

So set up 8 degrees retarded from what I've found to be the best setup?..yup..there ain't enough dizzy advance in the world to correct for that.;)
 

badmuttstang

redneck grease monkey
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Oct 25, 2009
Messages
2,807
It dose sound like valve float until you mention it runs fine when not in gear if the valves where floating (to weak of a spring) then it would do it all the time. Stupid question are you sure the distributer has been stabbed right not a tooth or two off that would explain the timing being so far out that you can barely see it. Just something to look at. As far as the balancer being wrong what I meant was it could be off a 351M or 400 and the timing marks would be off for a Cleveland.
 

pcf_mark

Bronco Guru
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Jun 11, 2010
Messages
3,566
As others have stated you may need to go back and check your basics. Check the cam events for #1 against the balancer and pointer. Then check the distributor for #1. I have seen the pointers on SBC, BBC and SBF incorrect by 4 - 8 degrees in stock location. I also had a windsor with incorrect pointer and it was similar to your behavior. The mark was waaay off. You need to sort that out before you go after camshaft/springs other stuff. Even if the cam is off 4 degrees it wont run with crazy timing numbers of 40-60 degrees like it sounds like you are reading.

For your 3000 rpm issues check your wires and cap first in case you are getting spark jump at higher rpm either inside the cap or across the wires. Also if you have a crack in the cap and the spark is jumping around it will explain your weird timing because #1 is getting a bad signal occasionally.

Can you get it act goofy under no load in the driveway or just on the road?
 

roundhouse

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Joined
Sep 5, 2003
Messages
2,886
Sounds like the cam has jumped a tooth or 2 on the timing chain.
I dont pay any attention to what the marks say, I just advance it till it pings under a hard load, like pulling a steep hill, then back off a 2 or 3* or hook up a vacuum gauge and advance until you get max vacuum.
 
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