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chevynuts88 said:
A friend came over and set the timing " according to the timing tab" at 40* initial. He is well aware that sounds rediculous but thats where it runs best.By the way, when I purchased the car the timing tab was welded to the timing cover at the 12 o, clock positon and now it is in the regular position where you normally see them[between 2 ad 3 oclock]. He replaced my squirters to a size smaller because " it smelled way too rich " and the stumble was considerably less.It still stumbles a bit when first flooring it, he suggests smaller primary jets and needles.Ive never changed jet sizes ,how much smaller should I get? Any ideas?
Did you change your dampener (or re-mark it) when you changed to the 2 o'clock timing pointer??? If not, you might as well set the timing using a blindfold. Also, based upon what I just read, I wouldn't let your friend work on your car again :eek:



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Several things can happen to make the marker wrong. Why not bring #1 up, find true TDC, that will require a piston stop and rolling the engine over til the piston hits the stop in both directions then splitting the difference on the balancer which will be TDC. You may have to relocate the pointer to get this right. That would be the best thing to do IMHO. RM
 

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Discussion Starter #23
I changed the timing cover and damper[new GM] at the same time .I think the damper was the same as what came off.I looked at the two dampers to see if the timing marks and the keyways were in the same place and they appeared to be.I put the timing gears and chain on myself knowing how important it is too have the dots lined up.I would bet large sums that they are correct.Which part of his advice don,t you like?
 

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chevynuts88 said:
I put the timing gears and chain on myself knowing how important it is too have the dots lined up.I would bet large sums that they are correct.
I would have too since I was the one to put the chain on, BUT it turned out I was wrong...:eek: ....of course I'm not saying you made the same error I did.....just giving my 2 cents:)

Again, since were not there its hard to trouble shoot, BUT to me, JMO, 40 degrees of intial timing is wrong..when your 21 degrees of advance kicks in your over 60 degrees of total advance...again to me that would, based on my previous experence, lead me to think something is amiss with the setup....:eek:

BTW we're NOT trying to bag on you, your car, or your friend, were just trying to help out...NPHNP:)
 

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chevynuts88 said:
I changed the timing cover and damper[new GM] at the same time .I think the damper was the same as what came off.I looked at the two dampers to see if the timing marks and the keyways were in the same place and they appeared to be.I put the timing gears and chain on myself knowing how important it is too have the dots lined up.I would bet large sums that they are correct.Which part of his advice don,t you like?
I just don't want to see you have something get screwed up. Something is wrong with the timing. Either the dampener is wrong for the 2 o'clock pointer, the chain is off like Duane said, etc...that needs to be addressed BEFORE you turn your attention to the carb.



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If the damper is the same as the one that lined up with the 12 o'clock timing tab how did it line up with the 2 o'clock timing tab? What PN was the damper? I can look it up and see what it's for.

The engine can't possible take 40 degrees initial timing much less add 21 degrees of mechanical advance. Your timing indication isn't right so it's worthless. You don't want to set timing by ear. This is a sure way to destroy your engine. Are you sure you have the inductive pickup on the correct plug wire? #1 is the front cylinder on the drivers side.

If that's right then go back to square one and verify the damper mark lines up with the timing tab 0 mark at piston #1 TDC. You'll need a piston stop to verify #1 is at TDC. Don't use any other "short cut" method. I'll bet the damper is 30-35 degrees off because it's for a 12 o'clock tab, which is off a later engine like a 305. If it has a channel as well as a timing line it's a 12 o'clock damper. The channel was for an inductive pickup that goes in the tube on the timing cover.

See pix.

Another confusing issue is before 1969 (327's) had the timing line indexed to 2 degrees before the keyway. 1969+ engines used the later 10 degree before the keyway timing location. So you have two timing tab locations and three damper indexing locations (plus the diameters and widths).

If you mix up the parts the timing won't be right. Not to mention those crappy chrome timing tabs that are junk.

Read up on dampers here: CHP Damper Dance tech article
 

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In the mid-1980's, small block engines got a timing mark change, to the 12 o'clock positioning, because of all the accessory drive brackets. All those brackets obscured the 2 o'clock timing tabs on the sides of the covers. These new covers, with the noon positioning tabs, were designed to have the tune-up wizard read the scale from the TOP of the engine downwards, behind the water pump.

What is now needed is to positive stop the number 1 cylinder and confirm the side TDC reading just to qualify that the whole thing is correct.
 

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If your timing is too far advanced, you'll have a hard start condition...tur--------rur------rur, instead of tur-rur-rur, (especially when the motor is warm) and you'll get a lot of pinging. Try going up a hill slowly and then romping on the throttle a bit...if you hear lots of pingning, your timing is probably too far advanced (crappy gas will also cause this). You should shoot for 30 some odd degrees in by about 2,500 rpms; my 327 ran great with about 36 degrees in by 2,500 with a mechanical advance accel BEI setup. I would also suggest that you document the timing readings and then go for a ride. Each time you make a change note the difference. Use the best response as a baseline, even if it appears way out of wack, and then try other things (i.e., squirters, power valve, etc.).
 

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Discussion Starter #32
Is there a location I can use [for a pointer] that is better than the new timing tab [2 oclock positon]? Won,t the new lines that I have to make using the piston stop idea be behind the water pump?
 

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Piston TDC is TDC. It is very important your timing reference is EXACTLY showing piston TDC.
You can put a tab anywhere as long as the line on the balancer lines up when the piston is at TDC.

Here's a thread on finding TDC.

You have a couple of options if your balancer is marked for a 12 o'clock timing location.
1. Change your damper.
2. Rescribe your damper or use a timing tape.

Somewhere Mike Goble had a post on degreeing a balancer. Look for it.
 
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To move the 12 o'clock timing indicator to the 2 o'clock position, easy. There are aftermarket timing scales that bolt to the 2 o'clock positiuon, two bolts on the timing cover. Then, TDC the engine and make a new TDC line on the dampener for the 2 o'clock scale, done, go time it and drive it.

I've actually seen some large vans, motorhomes and trucks with the timing scale on the bottom of the timing cover, 6 o'clock position, bevcause there isn't any way to read them any other position. This just goes to show, YOU can make the scale fit any place, then, TDC, make the line, time away.

Paul's diagram with the two pointers on it above should give you the idea.
 

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Discussion Starter #35
still confused!

I pulled the plugs ,put a piston stop in rotated cw till it stopped and marked the balancer,rotated it ccw until it stopped and marked the balancer again. Without a degree wheel attached and using my marks and measuring between the marks [tape measure] and dividing by two it is within two degees of the mark [not 30 which I was hoping it was]. If it shouldn,t run with this much advance and the starter is not grunting would you pull the timing cover off to double check marks or is there something else to try first?
 

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chevynuts88 said:
I pulled the plugs ,put a piston stop in rotated cw till it stopped and marked the balancer,rotated it ccw until it stopped and marked the balancer again. Without a degree wheel attached and using my marks and measuring between the marks [tape measure] and dividing by two it is within two degees of the mark [not 30 which I was hoping it was]. If it shouldn,t run with this much advance and the starter is not grunting would you pull the timing cover off to double check marks or is there something else to try first?

I would...:)
 

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I must be confused. If I read the post correctly you put the piston stop in and rotated clockwise until it stopped, marked the balancer and then rotated counterclockwise until it stopped again and marked the balancer, then measured between the marks you made and split that difference in half and it was within 2 degrees of the top dead center mark on your pointer. Is this correct? If the pointer would have been exactly at the center mark you made it would have been at top dead center so it appears to me your pointer is off only 2 degrees. I don't understand the remark about you expecting it would be to be 30.
 

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wskaiser said:
I must be confused. If I read the post correctly you put the piston stop in and rotated clockwise until it stopped, marked the balancer and then rotated counterclockwise until it stopped again and marked the balancer, then measured between the marks you made and split that difference in half and it was within 2 degrees of the top dead center mark on your pointer. Is this correct? If the pointer would have been exactly at the center mark you made it would have been at top dead center so it appears to me your pointer is off only 2 degrees. I don't understand the remark about you expecting it would be to be 30.
read this thread it will get ya up to speed;):)

I merged the all the threads together. It's more helpful when all the information is in one place ~ Paul W.
 

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Something is wrong here. You can't have 40 degrees of initial advance and 21 degrees of mechanical advance. If you did the TDC check right then I'm temporarily stumped. I merged all your posts together so we can have the clues in one place.

What kind of timing chain set do you have? Did it have multiple Keyways?

Can you take some clear pictures of the engine? I want to see the distributor, plug wire routing, the balancer and timing tab.
 

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Discussion Starter #40
I,m going to pull it apart tomorrow morning and see if the timing chain is on correct [the dots line up]. If nothing else it will put my mind to rest. Ive had enough of this second guessing! While I have it apart I will take photos and put them on here one way or the other! If I,ve put it together wrong I,m man enough to admit it! I just want it right! I,ll make sure while I have it apart that any info [pics or whatever] will be shown. Thanks for the help guys,I,ll keep you posted.
 
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