Total timing above 38 deg.??

[Scotty_S-15]

Seems like there\'s been a lot of discussion lately about guys running excessive total timing, and/or guys simply not bothering to check total timing. I know how important this is, I could be the \"poster child\" for this problem. About 4 years ago I had an engine fail because of that. The irony is that I had ALWAYS checked total timing. (details later)



Too Much timing did THIS (http://s10v8.com/members/Scotty_S-15/piston_04-99.jpg)



....... For those who don\'t know, and would like to know, total timing is what you see with your timing light, with vacuum disconnected, at the highest RPM possible, but usually total timing should be all done by 3K, but go higher just to be sure. Messing with initial timing is fine, but you should never exceed 34 or 36 degrees total timing, unless you have very special requirements.

.......... So you say that your timing tab only goes to 15 or 20? And you don\'t have a dial-back timing light? No problem, just get a $10 timing tape (proper one) and stick it on your balancer, and highlight the 20 or 30 degree mark with white out or something. So then, the new 20 degree balancer mark, lined up with the 14 on the timing tab is 34, etc. Basically you\'re just extending the timing tab.

........... Or, if you want to do it \"right now\", just measure the circumference of the balancer, divide by 360, mulitply by 20, and then put your mark there. (or just divide by 18) (This distance should be double what 10 degrees is on you timing tab) A good thing to measure the balancer might be your wife\'s or GFs sewing tape thing. Well, good for you, not for the tape! http://www.s10v8.com/images/smilies/icon_razz.gif That\'s what I\'d use, but my wife doesn\'t sew! http://www.s10v8.com/images/smilies/icon_biggrin.gif

[wild85]

scotty



If my timing is at 43 total, how much should I turn the distributor to make it 36? counter clockwise to retard right?

[Scotty_S-15]

No, turn it clockwise looking down at the rotor, not from the oilpan side. http://www.s10v8.com/images/smilies/icon_razz.gif The rotor goes clockwise. Turn it exactly 1-1/2 smidges.http://www.s10v8.com/images/smilies/icon_eek.gif http://www.s10v8.com/images/smilies/icon_confused.gif Seriously, you\'ve got to use a timing light. If you want to retard it 7 degrees at the balancer, you\'d need to turn the dist. 3-1/2 degrees (\'cause it only goes half speed) And you can imagine that that ain\'t much.

[Scotty_S-15]

So getting back to the saga of my \"detonated\" engine.... I think I fell victim to the \"slipping balancer\" thing, but I\'ll never know for sure.

..... BTW, in the pic, you\'re looking at the second ring. Top ring in that area busted up, and beat up the top of the piston, guess it went out the tailpipe. Believe it or not, I gave those heads away (old iron 1.94 double humpers) and the guy just bolted them on and ran great.

...........Sequence of events, spring 1999:

* Engine was running crappy, not idling right, etc., tuned it up, plugs, timing, check floats, etc. still crappy. Went racing, ran OK, nothing great. With that engine a 13.2 @103 was the norm. Drove it home, parked it, no problem.

* The next day, went to start it, all sorts of NOISE immediately. The outer ring of the balancer slipped completely off, rubbing on the timing cover. WTF? It was running OK when I shut it off.....

* I order a new balancer, shows up in a couple days @ 4PM on Friday... Hey, I can go racing tonight if I hurry! I pop the balancer on, and off I go. It\'s still running shitty, especially at lower speeds.

* I race, and at the top end, I think I hear a spark rattle.... Hmmm, I NEVER heard this engine do that..... I had a timing light.... I check it... Oh nice, 50 F\'n degrees total!! How the hell?? I set it back to 36, and now it\'s really running shitty. I do a bunout, and thought I smelled blowby.... screw it... I blast off, run like a 13.5..... and now it\'s really stinking and mucho blowby.

* I drive it home, next day I start to do a leakdown test.... don\'t get very far when I notice that the air I\'m putting in #5 plug hole is coming out the breathers BIGTIME. You gotta know that ain\'t right. Next step is what you see in the pic.

* So what happened? Dunno. Did I set the timing after the balancer had moved a little? Maybe. Seems the obvious answer, but I just don\'t know.

[speeder]

I think that some of those out of the box balancers are not balanced. My builder said this and I had him balance everything before I used it. He drilled like 7 holes in the flexplate and the balancer. NEVER TRUST the aftermarket, but not even the general himself. I would also make sure that TDC is TDC the timing tab can be anywhere on the timing cover, once again never trust anyone that sells stuff for your motor or trans or just your truck (baby, best girl, pick a name) and check everything. I totally agree with you on the writeup and I want to add 1 thing.

I think that if you (proverbial you) race and try to run below 13s, a dialback is not a big investment. Your wheels and slicks cost 3X as much as the light did.

[ZeroGravity58]

i dont know but i bought a new balancer and one of them bolt on timing marks that go on the dirvers side of the timing cover. TDC seems to line up but its hard to tell. I had the timing at 34 total but after messing with it today i have a feeling its up near 40 but its not detonating. It seems like wild95 is haveing the same problem and we are running the same heads...could it have something to do with low compression?

[Knanthrup]

guys, isn\'t 34 degrees basically underneath the waterpump? or is the turning the opposite way? this is in reference to a drivers side timing tab, mine only goes to 16 degrees before and like 12 after

[Scotty_S-15]

On 2004-12-15 15:26, Knanthrup wrote:

guys, isn\'t 34 degrees basically underneath the waterpump? or is the turning the opposite way? this is in reference to a drivers side timing tab, mine only goes to 16 degrees before and like 12 after



That\'s right. And that is the reason you either need a dialback timing light, or use the procedure I mentioned at the top of this thread. Personally, I don\'t like the dialback timing lights... I\'ve got a Snap-on dialback that somebody GAVE me, I still don\'t use it.... I guess simply put, I don\'t trust it, it trust myself to use it properly. I use a old, crappy Craftsman timing light. When the plug fires, the light fires, no chance for error.

[Scotty_S-15]

On 2004-12-15 12:40, speeder wrote:

I think that some of those out of the box balancers are not balanced. My builder said this and I had him balance everything before I used it. He drilled like 7 holes in the flexplate and the balancer.



.......... Not wanting to stir up a hornet\'s nest, but if your builder did what I think he did, he didn\'t do you any favors. Chances are that the balancer and flexplate WERE balanced properly when you gave them to him. But he drilled THEM to help balance the crank/reciprocating assy. Now that might be OK, but what happens if you need to replace either the balancer or the flexplate? I don\'t think you want to take the whole engine back to him to get it balanced, ya know?

......... If the balancer and flexplate were originally neutrally balanced, and he did them individually, then yeah, that\'s OK. But I doubt if that\'s what he did.

[MARKYMARK]

hey scotty didn\'t your engine want to kick the starter back while trying to start it with that much timing. oh wee years ago when i was 18, i popped my dist. back in and set by ear. but when starting wow sounded like a 5 lb sledge hitting the flywheel while cranking. ran to my cousin\'s asking whats wrong

[Scotty_S-15]

Yeah, Marky, you\'d think that it wouldn\'t want to start.... But I did always ran a good 18 degrees of initial, and when hot, sometimes wouldn\'t want to crank over, but I have an ignition kill switch. Kill ignition, spin it over, and hit the ignition, that usually worked.

.......... I just don\'t know exactly what happened. Another thing that bothers me, is that if the balancer had slipped some time earlier, I certainly would have been suspicious with having to advance my timing 15 degrees to \"make it right\". So that didn\'t happen either... Just dunno.

........... At the time I was suspicious of the distributor. Not likely anything inside could make the timing jump up 15 degrees, but it was a junkyard HEI, so just to be safe, I tossed it in the trash.

........... I even thought that maybe the cam jumped a tooth, but that would have been more than 15 degrees, and would probably have gone in the other direction... Not to mention that it would probably not even run. Keep in mind, that the last pass down the 1/4 mile, with a busted piston, it ran a 13.5. only 3 tenths off a normal time. So everything was still working pretty good. A real mystery.

[speeder]

I believe that most of the cranks are balanced on the ends in the SBC and that the flexplate and the balancer has to be balanced on its own, just true balance. I could be wrong, but the 400 is the only SBC that is externally balanced. I do not think that you need to have the entire motor taken back, just the new parts. Let\'s just say that I am wrong and you need to have a crank there to have the balancer/flexplate balanced right, most machine shops have an extra SBC crank around that can be used to bring that balancer/flexlpate to very close to perfect balance.



About the heads, if you have steel heads, then they retain heat better and can have higher timing with less compression. With the aluminum heads the heat disspiates better in the heads and therefore they require more compression to run the same timing and spark plug heat range. So I would try and tune the timing and the carb based on what you have, not what everyone says. Every vehicle is different here, so just spend a day testing and tuning and taking good and thorough written notes and the truck will run much better.

[Scotty_S-15]

On 2004-12-16 10:19, speeder wrote:

I believe that most of the cranks are balanced on the ends in the SBC and that the flexplate and the balancer has to be balanced on its own, just true balance. I could be wrong, but the 400 is the only SBC that is externally balanced. ................

You are absolutely correct. Also the 1-piece rear main seal engines use a \"counterweighted flywheel.

........... But what I was getting at, is that many engine balancers like to add or deduct weight to the harmonic balancer and flywheel to balance the whole assembly, instead of working on the crank. That sucks. Also, many engine balancers insist you give them the balancer and flywheel, but DO NOT add or deduct weight to them to balance the rotating assy., and that is just fiine.

...... You said your guy drilled a bunch of holes in the flexplate & balancer, right? Therefore, I\'m guessing that he did not balance the flexplate & harmonic balancer individually, but rather used those pieces to balance the crank assy. Hence, if you need to replace either flexplate or balancer, the rotating assembly will no longer be \"perfectly\" balanced.

[ZeroGravity58]

see i dont understand this. Scotty said he ran 18 degrees initial and his motor cranked over slowely. Something must not be right with my timing then and this could be one reason im having so much problems. With my fully mechanical Mallory distributor im running the medium (silver) springs. All my timing is in by say 2,000 RPM\'s Right not according to the timing mark im running almost 40 degrees total and like 24 initial. I never have a problem getting it started hot or cold. Even the last few mornings its been in the 20\'s when i got to work and it starts up perfectly fine. Is there a way to time it by ear to see if i can get it any better. This maybe why it hesitates and all sometimes because the timing is to far retarded, eventho i have fixed alot of it. I have been trying to time it by ear but if someone could explain it to me. thanks

[Scotty_S-15]

The slow or stalled cranking because of too much advance usually occurs when the engine is hot. Compression and other factors seem to affect this syndrom.

...... Regarding ZeroG\'s situation, I\'m sure I\'ve harped that you\'ve got to prove your TDC mark is correct, and I think you said you did? That would explain it all, if your mark was off.

[ZeroGravity58]

i think i have. But it could be off abit either way. Because i have a 76 block and crank. Im using the newer style balaner and bolt on timing tab on the driverside. I think its right but im not positive, when i found TDC i put a small screwdriver in the sparkplug hole to make sure but there is some error to that. Im also only running like 8.5:1 compression.

[Scotty_S-15]

I think you should get the $10 tool, and check it accurately, doesn\'t take all that long to do.

[ZeroGravity58]

i will have to buy one and check it out. but right now i dont hear any pinging and the trucks runner very good.