|01-24-2013 06:26 PM|
- First Chevy uses number one on the drivers side as the number one cylinder that timing is checked from, I'm assuming your light is hooked to this, if not this would be the thing to do.
- Second would be you've got a high resistance ignition wires which cut off part of the ignition signal (a thing they're supposed to do) which delays the inductive coupling of the timing light from forming enough voltage to trigger the light when it's needed in a timely fashion for accurate measurement. things happening fast a small delay within the inductive coupling can be a lot of crank degrees.
- Third, the cam is a tooth or two out of time and needs a lot of advance from the ignition to operate the engine.
|01-24-2013 05:27 PM|
Hold your head up
Have you tried restabbing your distributor? somthings off cause I dont believe your actually running those numbers. You said you got it running by ear right? So it must have been sounding normal, then you checked and it was off right? well I dont think it would ever sound normal at 60.
So, here is what we can assume.
Either your distributor, balancer, TDC, timing light,...
thats about it. One of those isnt right. I know its a bummer to continue to do things over and over but since its not right you have no choice.
Just try going at it on a fresh day, and re-stab your distributor. This has to be perfect and there is a ton of videos on you tube showing tricks and common issues. double check everything make sure the clamp that is attached to the number one wire from the timing light is facing the right direction. make sure the vacuum advance is plugged at both ends. make sure you are using the correct timing tabs, I know this has been stated already but you would get a 60 reading at the 2 oclock spot if you were really needing to be at 12 oclock. (maybe). Most likely its not running at 60 and the numbers your getting are incorrect. which is a bummer but better than having an engine running at 60 advanced.
Ive seen guys put heavier springs in the distributor when checking initial just so they know they are not getting a false reading cause by mechanical advance showing face while its idling. Then put lighter springs back in so you know its opening all in by 3000. I actually use one med. and one light in the final product. just seems to work good for my set up. I also have vacuum advance and after reading all kinds of stuff online about how its a must in street driven vehicles, I took some advice and plugged it for driving and it accelerates much better and now never exceeds 34 degrees. Even sounds better when accelerating.
Hopefully, this msg will get your spirits up a lil, I know how frustrating it can be. Hell, I bet we all have been there one time or another so we want nothing more than to help. Im no pro either, just this last year I have been through this many times, and I continually resort back to these forums or you tube for help.
|01-24-2013 01:56 PM|
|bowtie44s||Like i said, I have used 3 timing lights. With the piston stop, the mark on the balancer lines up with the 0 on the timing pointer. I do not have a MSD box.|
|01-24-2013 01:20 PM|
I know you said you used a piston stop to verify TDC, but if this is a sbc engine you're working with, there are several different combos of timing tabs/damper lines, so you might want to double check what you have.
|01-24-2013 12:38 PM|
Could the spark plug really be firing when the crank is 60 degrees btdc at idle? I wouldn't think it could run let alone start. I'm just wondering if it's actually firing at 12 or 14 and somehow i'm coming up with 60.
|01-22-2013 02:03 PM|
As long as you've confirmed TDC, firing order, etc. like you have, unless the carb is way out of tune/faulty/"modified", there's no way it should need anywhere near that kind of timing. So I'd start w/the carb:
As long as the carb is working right and not too far from factory specs, I'd start by baselining the transfer slots of whatever carb you're using. Then use initial advance and idle bypass air to get it to idle w/o the primary throttle blades being open too far. This can be done in several ways depending on the carb; a Holley can use the secondary throttle shaft adjustment screw to tip them open a little. If bad enough (although this is rare) holes can be drilled in the primary blades, but that's only as a last resort.
|01-22-2013 01:47 PM|
|bowtie44s||I have the small block cam retarded 4 degrees, the big block is straight up. I haven't messed with the small block for a while. I am adjusting initial timing. I don't know when the mechanical advance starts but i would assume after 750rpm. I have the vacuum advance unhooked and when i slow the timing much below 60 it starts idling rough and will die.|
|01-21-2013 05:26 PM|
Read this, and then if you have any more questions just ask.
|01-21-2013 02:38 PM|
weird timing issue
You know it sounds like to me that you do not have the crankshaft gear set straight up. It's probably one of those crankshaft gears that have 3 keyway settings. One keyway has a dot, the next has a square, and the other has a triangle.
|01-21-2013 01:18 PM|
|bowtie44s||I will do the piston stop again. This weekend. That makes sense but it seems strange that it lined right up with the factory balancer mark. I'm out of ideas so it's worth a try. I'll post back when I do and let you know what i find.|
|01-21-2013 12:52 PM|
You obviously have a fudimental problem with your timing mark or light. If you have 60* initial and an aditional say 24* mechanical advance there is no way it could run with 84* advance unless you were using candle wax for fuel.
"There is 45* distributor rotation between cylinders so the rotor should be almost to the #8 plug."
The rotor should be pointed right at or just after #1 terminal on cap at TDC.
If you rotate the engine to say 12* before TDC, the rotor should be pointed directly at the #1 terminal if your using close to stock advance.
Any chance the balancer ring has rotated on its hub(happens all the time).
Any chance that when you used a piston stop that the engine got stuck in its rotation before the piston hit the stop in either foward or reverse rotation making you think it hit the stop(stopping in its foward rotation would result in an over advanced "zero" indication if I'm not mistaken). Did you unscrew the stop a little and see if the you got the same results?
Any chance that you put your mark on the opposite side of the balancer between the two marks? If you had the piston stop screwed in to far it could be an easy mistake. I really think you should try the piston stop method of finding your TDC mark again! I know your certain thats not the problem, and thats where your having so much diffuculty. I agree that its probably not 3 different lights, although I've had severe problems with a dial back light on my MSD 8365 HEI.
I was an electronic technician for over 20 years, and one of the 1st things I learned about troubleshooting a problem for someone else is not to take their word for a diagnostic step they found to be ok as that was often incorrect and the reason they couldn't fix the problem.
|01-21-2013 12:37 PM|
Haven't checked the compression, the shortblock is stock. The heads shouldn't have upped the ratio any so i'm guessing around 8:1.
@.050 218int/228exh lift .500/.500 lsa 114 so fairly mild cam for a big block.
|01-21-2013 12:16 PM|
|lmsport||How much compression and what are the cam specs.|
|01-21-2013 12:07 PM|
|bowtie44s||I have timing tape on my 8" balancer and the mark lines up at tdc. The pointer is at around 2 oclock. I checked the mark so it's right.|
|01-21-2013 09:54 AM|
weird timing issue
If you are standing in front the vehicle. Looking at the timing chain cover and the top of the crankshaft, where is the timing scale located. Use the postion of the hands on a clock. Is it at 12:00 or at 2:30?
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