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Discussion Starter #1
So, first the setup- I built a 1968 327, it is .060 over, has 1996 Vortec cylinder heads edelbrock vortec performer intake manifold, 600cfm edelbrock performer carb, cam is Comp Cams XE262h. Engine runs great and has for the last 2000 miles. Engine is mated to a stock 200-4R with very highway friendly 2.41:1 LSD rear end.

Second, the issue- I recently acquired a timing light for the purposes of setting my timing to the proper specifications for vortec heads. Now I am pretty certain that initial timing advance for these cylinder heads should be 10* and total should be around 30-32*. The problem is that at idle with vacuum advance plugged she's advanced 48*:wow: and total timing is beyond the 60* limit of my timing light:nervous:. When I try to drop her down to 10* initial she dies at around 30-32*.

Now, the question- Did I Eff it up? or am I just missing something simple? Could anyone shed some light on this issue?
 

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the small block has 3 different timing mark set ups verify tdc then re check your timing,im sure your mark is off
 

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Once you determined your timing marks are
correct. Set it at 8* btdc total is 36* all in by 2600 rpms.:beer:
 

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Discussion Starter #6
I went in and made sure cyl #1 was on TDC. (Finger in the plug hole, and rotate engine by hand) the wierd thing is that the mark in the balancer was actually in line with the 0* mark on the timing chain cover. But still the wierdness persists. I did buy a new balancer for the engine due to the old one being spun. But like I said it lined up with 0 at TDC cyl#1. I am now thouroghly confused. :-? hmm... Is it possible that my timing light is out of whack or something?
 

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Timing error.

Chevy balancers come in two sizes and the timing mark is not nesessarily in the same spot on the edge. You must use the correct balancer with the matching timing tab to get a correct timing reading at the crank.
 

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Chevy balancers come in two sizes and the timing mark is not nesessarily in the same spot on the edge. You must use the correct balancer with the matching timing tab to get a correct timing reading at the crank.
Well, ya beat me to the punch on that one. That was my recommendation.:beer:
 

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Discussion Starter #9
I thought that might be the case as well which is why I put it on TDC Cyl #1 and checked my balancer and timing cover marks, as I mentioned above it was at 0*. I think I'll just get a programmable MSD distributor. Thanks for the help guys. I really appreciate it.
 

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hey Raz just double checking,, you sound like you know what your doing.:texas:
but you didnt say how you knew the piston was at the top of the stroke??

yea it sounds like a bad timing light,, theres not much chance of it starting and running right at 48*..
is that a fancy digital, rpm, advance timing light??
i never had one,, and i dont think it matters on the timing,,
but do you have to tell it how many cylinders??
just guessing..:dontknow:
 

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Discussion Starter #11
My timing light is a cheap one that I got from Harbor Freight. There isn't a provision for changing the amount of cylinders or anything cool like that. All it has is positive, negative, Cyl#1, and the advance wheel on the back. I've seen the ones where you have to specify the amount of cylinders. Mine isn't one of those. It says that it is for all engines up to 8000 RPMs. I think that it lies. I'll just get a better timing light sometime. Thank you to everyone who helped with input. I really appreciate it.
 

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An accurate timing light will not work on 4,6,8 cylindered cars the same without changing it.
 

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If the distributor you are running has a mechanical advance, unhook the vacuum advance and plug it. Set your base timing at idle, at 10 or so and then bring up the rpm's and see what total timing is, I would shoot for about 34*. Leave the vacuum advance plugged off.
 
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I'm having the same problem except I started with a timing light I picked up at a pawn shop. Figured there was something wrong with it so I took it back. Got the same one from harbor freight. Still having the same problem. Probably not the light. I knew the readings couldn't be right because it started and ran fine. I was just checking and maybe fine tuning. It has been sooo long since I've had to mess with timing. I knew I was on #1 coming up to tdc but I didn't actually check the movement of the piston. I just lined up the mark on the scale. Now it's all starting to come back to me. That's why I used the search, I knew someone else out there had to have had the same problem


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I guess I have led a sheltered life because I don't remember ever seeing a timing light that needed to know how many cylinders the engine was. Can't figure what that would have to do with it. Dwell - yes, timing I'm confused again.:???:
 

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I can only imagine the OP has one or more of the following issues.

  • mismatched pointer to balancer
  • bad balancer
  • is using the timing light incorrectly
There is no way the car would run with 45 degrees initial and well over 60 at cruise without hammering itself to death, if it would run at all.

In all likelyhood the OP is using the light incorrectly, my light which is an Equus 5568 can check dwell and as such needs to know how many cylinders the car has, it needs the cylinders only for the dwell portion of the meter, the number of cylinders is irellevant to the timing light portion.

When timing it needs to know if its a 2 cycle or 4 cycle motor and its inductive pickup wishes to be oriented in a particular way (one side pointed towards the plug)
 
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It's kind of idiot proof. You point and squeeze. The advance knob on the back rotates from 0-60 degrees. I need to set the advance around 50 to even get the timing mark to show up on the scale. I'm sure it is a mismatched set of balancer and scale. I just haven't had time yet to get into it. Point is I don't think he or I are using the timing light incorrectly


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As has already been pointed out, there are two different harmonic balancers (not counting the different diameters).

One has the timing mark directly in line with the key way and is at the very top of the balancer when at TDC.

The other has the timing mark to the right of the key way and is down the right side about 30 degrees (my estimate) when at TDC.

Whichever one you have, you need the appropriate pointer.

Sounds like you have mismatched balancer and pointer.

As also stated, be sure to disconnect the vacuum advance when setting initial timing (10-14 degrees).

The old school way to set timing is to advance it until it pings and then back it off until the starter doesn't drag when cranking.

Jack
 

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There's also another way using a vacuum gauge. Go for max vacuum, then give a test drive. If it pings, back off about about 2* at a time until it stops. If starter drags when hot, about an extra 2*.

I think I have the same setup, a mismatched balancer/pointer. Pointer is on side, but read timing from on top. I hate those on top readings. Too hard to get to, and I'm not likely to stand on something to read the timeing, only to have the stand slip from under me. Bad on the ribs, and mine are brittle with age.:twisted:

Oh, and Neil, when I made the comment about the cylinders, I'm used to using mine with the dwell which has to be set. Actually, not a problem for me. Only work on V-8's.
 
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