Initial timing at 50???

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Budgetmoparman

Budgetmoparman

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Trying to get my 340 timed today and something is crazy. I had the initial timing at 50* before it kicked back on the starter. It starts great and idles great around 43-45*. I checked the timing marks and verified that 0 is TDC. I used a dial back light and a cheaper non dial back light and get the same thing. 70 340, comp XE268 cam, not sure of compression- basically stock build with cast heads, msd 6al box, factory distributor- tried 2 different sets of springs, taylor 8mm wires, autolite 65 plugs, balancer is aftermarket street/strip- can't remember the brand. What the heck is going on with this thing? Vacuum advance is blocked off.
 
Did you build the engine and know how far in the hole the pistons are? I've had a couple of engines that liked 50 TOTAL but they sure weren't 50 initial. Low compression engines (8-1) usually like a lot of total timing. Pistons 'advertised' for 10-1 are usually not even close so they need to be ordered according to compression height......
 
Put a timing tape on it, I bet your light is jacked.
 
Marcohotrod said:
what does it go to when revved up? will knock like hell when warmed up and accelerating
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I haven't been able to drive it but when I rev it up it revs great, no knock. When I bring the rpms up it will go to 58* but doesn't go any higher.
 
Cranky said:
Did you build the engine and know how far in the hole the pistons are? I've had a couple of engines that liked 50 TOTAL but they sure weren't 50 initial. Low compression engines (8-1) usually like a lot of total timing. Pistons 'advertised' for 10-1 are usually not even close so they need to be ordered according to compression height......
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I built the engine, pistons were .018 out of the hole. I don't have a burret so I didn't measure for actual compression ratio. It is basically a stock 340 so it isn't real high compression.
 
Budgetmoparman said:
I built the engine, pistons were .018 out of the hole. I don't have a burret so I didn't measure for actual compression ratio. It is basically a stock 340 so it isn't real high compression.
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.018 out....shouldn't be lacking for compression! You might check your lights with someone else to see if they show the same thing as there's or have them check your timing with their light. I did that the first time I ran across a similar situation.
 
sireland67 said:
Put a timing tape on it, I bet your light is jacked.
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The marks on my balancer go to 60*. I checked it with a regular light and a dial back light and it is the same. I double checked the timing marks on the balancer and they are correct according to the timing marks on the timing cover.
 
Cranky said:
.018 out....shouldn't be lacking for compression! You might check your lights with someone else to see if they show the same thing as there's or have them check your timing with their light. I did that the first time I ran across a similar situation.
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I will have to borrow a timing light and double check.
 
I tried retarding it to 20* and it won't idle for ****. I tried adjusting idle circuits on carb but it didn't help.
 
Cranky said:
.018 out....shouldn't be lacking for compression! You might check your lights with someone else to see if they show the same thing as there's or have them check your timing with their light. I did that the first time I ran across a similar situation.
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At .018 out of the hole, a stock chamber with a clean up cut and depending on gasket thickness you are about 9, maybe 9.5:1 at best. I've said it before, if you want 10.5:1 the piston needs to be .040-.050 out of the hole, depending on the thickness of the gasket.
 
yellow rose said:
At .018 out of the hole, a stock chamber with a clean up cut and depending on gasket thickness you are about 9, maybe 9.5:1 at best. I've said it before, if you want 10.5:1 the piston needs to be .040-.050 out of the hole, depending on the thickness of the gasket.
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Even a 9-1 shouldn't need that much timing.....
 
Are you SURE you are on number 1 wire with the timing clamp? Stranger things have happened. Also........check the polarity on the two distributor wires if it's a Mopar ignition. Make sure they are right.
 
yellow rose said:
At .018 out of the hole, a stock chamber with a clean up cut and depending on gasket thickness you are about 9, maybe 9.5:1 at best. I've said it before, if you want 10.5:1 the piston needs to be .040-.050 out of the hole, depending on the thickness of the gasket.
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I wasn't looking for 10.5:1. I just built a fresh motor with more hp than my worn out 360.
 
RustyRatRod said:
Are you SURE you are on number 1 wire with the timing clamp? Stranger things have happened. Also........check the polarity on the two distributor wires if it's a Mopar ignition. Make sure they are right.
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Hooked the timing light one inch from the plug boot so that wasn't the issue. The polarity should be right because the 360 that was in there ran just fine and I never had an issue timing that motor.
 
Budgetmoparman said:
Hooked the timing light one inch from the plug boot so that wasn't the issue. The polarity should be right because the 360 that was in there ran just fine and I never had an issue timing that motor.
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Well......SOMETHIN ain't right. Whether it's one of the things already mentioned, or something you've missed.
 
Done a compression test? Kinda curious what that might be....
 
Is the timing light clamp probe on the right way? There is a plug side, not all are marked. If wrong it, may trigger on start of dwell, not ignition, that would indicate advanced.
 
Not to be a smart ***......but you know that the front cylinder on the drivers side is number one.....same as a chev but different than a ford
 
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