30deg initial timing!?!?!!

[ol'blu72]

I finally have gotten back in my blazer after only driving it like 3 times in the last 2 years and decided to do some tuning. I set my timing "seat of the pants style" by driving it around town and making adjustments in random parking lots to get the best throttle response and power for all driving conditions. I was the best time I have had in a while. I got her dialed in and she runs great and pulls strong.
So i got her home and decided to check where I was at with my light and to my surprise she is sitting at nearly 30deg initial! I did some revving and mechanical advance is 30deg all in at 3500. This is just strange to me and I am thinking something is wrong. What do you experts think?

Details: Newly rebuilt (1000mi ish) 350 in a 72 blazer. Vortec heads, summit HEI dizzy, the mildest comp xtreme energy cam they got (probably similar to a RV cam). 350 tranny, 3.73 gears.

[68350]

I'm no expert on this but 30 all in sounds reasonable. My 496 is 36 degrees all the time(distributor is locked out). Did you have the vacuum line plugged on the vacuum advance when you checked your timing? Or is your vacuum advance even hooked up?

[67 chevelle]

If its 30 total at arround 2500-3000 rpms thats sounds right . It should be 8-10 inital at 800 rpms vacuum disconnected . Vortec heads are so efficient , they only need , and or run best at around 32 degrees total timing , where as most other small blocks like 34 to 36 total degrees

[ol'blu72]

No not 30 deg all in, it is almost 30 at idle! My vacuum advance was disco'd and plugged.

[ol'blu72]

I just went out and verified, my timing light is actually saying 38 deg initial and at 3500 (that's when the advance stops) I am approaching 60 deg.

[BMERDOC]

Do your advance weights move freely? I would also verify that the distributor is stabbed in correctly and not a tooth off.

[ol'blu72]

I am assuming so since I am getting about 20+ deg of advance from them. maybe too much but still haven't seen any sign of detonation. How do I verify if i am a tooth off?

[geezer#99]

Balancer slipped!!
Have you verified timing tab/marks?
http://www.crankshaftcoalition.com/w...op_dead_center

[67 cst swb]

Originally Posted by geezer#99

Balancer slipped!!
Have you verified timing tab/marks?
http://www.crankshaftcoalition.com/w...op_dead_center

Ditto

[jocko]

To answer your initial (pun intended) question - 30 deg initial is waaaay too high. Should be 6-10ish. So, if you're not hearing/feeling ping or detonation, I suspect the comments above are correct. Check the balancer vs timing marks etc for anything obviously wrong. The outer ring with the mark may have rotated relative to the inner hub. If that's bad, replace that bad boy asap. If balancer slip isn't readily apparent, then set tdc on #1 by any method out there besides your timing marks - and compare to see what is shows. It's easy and tempting to set initial timing too high by seat of the pants and your ear because it gives improved throttle response, but at a cost, and risk to engine. Since it sounds like your vac and mech advances are working (30 deg (correction 22 deg) increase from idle to 3500 rpm), really seems like a balancer or distrib install issue. Interested to see what you find out.

[67 chevelle]

sounds like its time for a new ballencer , no way thats right

[ol'blu72]

I replaced the balancer on the rebuild so it is brand new. You think the timing mark is just off on the new balancer? I never did verify it.

[geezer#99]

Originally Posted by ol'blu72

I replaced the balancer on the rebuild so it is brand new. You think the timing mark is just off on the new balancer? I never did verify it.

Never know until you check it.
Could be just mismatched tab and balancer.
What's your idle rpm?

[ol'blu72]

Originally Posted by geezer#99

Never no until you check it.
Could be just mismatched tab and balancer.

Damn Autozone! lol
Correct me if I am wrong but I dont think you can be a tooth off on your dist install. In my mind the only consequence of being off would be the indexing of the cap, I would just have to turn it more, one way or the other, to compensate. In theroy i beleive you can install it 180deg off but your cap would just be rotated 180deg also, and would make for fitment issues. Am I way off base??

[Boog]

You are correct. The distributor can be installed a tooth off either direction and as long as you can turn the housing to set timing correctly it is just fine. If say the vacumn canister hits the intake manifold runner before the distributor is turned far enough to correctly time it you can move the plug wires around by one terminal in the opposite direction to give more adjustment.
Being "off by one tooth" does not affect timing as long as you can turn the distributor enough to achieve the correct timing setting at the harmonic balancer timing tab. A lot of people do not understand this.

[BMERDOC]

Ah. The old slipped balancer problem. I forgot about that one. Seems balancers aren't the only thing around here. Haha!

[Custom/Ten]

Originally Posted by ol'blu72

Damn Autozone! lol
Correct me if I am wrong but I dont think you can be a tooth off on your dist install. In my mind the only consequence of being off would be the indexing of the cap, I would just have to turn it more, one way or the other, to compensate. In theroy i beleive you can install it 180deg off but your cap would just be rotated 180deg also, and would make for fitment issues. Am I way off base??

I am beleive this fella is correct. Guess I'm one of those people who doesent understand, tried to install my dizzy one tooth of once would not go all the way in and left a big gap. Perfectly willing to accept that I'm wrong, just sayin.

[Custom/Ten]

bottom of the shaft appears to only go in 2 ways. I don't get it. Please do explain though. I'm always up for learning some thing new and maybe we can help this gentleman in the process!

[Boog]

The reason the distributor won't drop in all the way is because of the oil pump drive shaft. All you have to do is pull the dist back out and use a long screw driver to turn the drive shaft a little bit and drop the dist back in or you can drop the dist in until it engages the cam gear then bump the engine over and the dist will drop on down when the drive shaft lines up right. Easypeasy.

[Custom/Ten]

Originally Posted by Boog

The reason the distributor won't drop in all the way is because of the oil pump drive shaft. All you have to do is pull the dist back out and use a long screw driver to turn the drive shaft a little bit and drop the dist back in or you can drop the dist in until it engages the cam gear then bump the engine over and the dist will drop on down when the drive shaft lines up right. Easypeasy.

I've heard not to bump the motor when the dizzys out so yea I'll buy that. Thanks

[geezer#99]

And it's always good to pass a file over the sides of the tang to clean off any small burrs. Especially on a new dizzy. I've had them too tight to drop into the oil pump slot.

[Ruscal]

Is timing light clipped to the number 1 plug wire? That would throw it off more than 20 degrees though if you were on the wrong wire.
Russ

[jocko]

I think it at this point, you really need to:
1) find TDC (not via the timing marks)
2) check to see where your balancer 0 line is relative to the timing pointer
3) if all that's good, look at the distrib and make sure that the rotor is at or slightly past the #1 tower

[mechanicalman]

Get one of these and find TDC:
http://www.summitracing.com/parts/sum-900189/overview/

Then determine what timing tab you need to match the balancer you got or if the mark is defective on the balancer. See pics below.
After finding TDC you could always just install timing tape the right size for your balancer and fix it that way.
http://www.summitracing.com/search?S...0Timing%20Tape
http://www.summitracing.com/parts/mr...make/chevrolet
http://www.summitracing.com/parts/mr...make/chevrolet
If you get a new pointer make sure it's right for your size balancer. They also make sleeves to go over the balancer (dress-up) but they are degreed and never slip.
http://www.summitracing.com/search/p...ancer%20Covers
Many ways to fix this, but you need to start with the piston stop. Go easy on it, if you yank too hard on the crank you will bend it but that's not necessary.

[BMERDOC]

Originally Posted by BMERDOC

Ah. The old slipped balancer problem. I forgot about that one. Seems balancers aren't the only thing around here. Haha!

Geeze, what a typo. "aren't the only thing SLIPPING around here".