Losing my mind trying to get this 360 to run right

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Ok guys so here's where I'm at. I eliminated one issue that I was having with carburation. I rebuilt my carter competition 750 and got it to idle. I'm still having a backfiring issue so I threw the timing light and vac gauge on there and the timing mark was waaaaay advanced and would hardly move back when when I tried retarding it. I thought I nailed my cam timing when I put it in at mfg specs but is it possible that could be that far off? For the most part when I installed it, it degreed out at pretty much straight up within a degree or so. I'm not worrying about it being to the nats ***. My dizzy I bought from KMJ performance on ebay. I haven't been real happy with it it's mainly a stock style distributor but aluminium and has a built in hei style system. Does that sound like it could be the culprit? Firing order is right on compression checks out great but I think I'm going to have to pull the chain cover and make sure my cam is where it needs to be. Could it have skipped a tooth? Its a new double roller so I'm just scratching my head. Any other input is appreciated.
 
Did you verify the timing marks on the damper to the indicator on the timing cover before you installed the heads so you could actually see TDC? I use a bridge gauge with a dial indicator and mark the damper to the cover. If you have a bad or wrong damper this could also be an issue.
 
Yea I did verify this. What I think I will do tonight before I pull everything apart is pull the valve cover and look and see what the valves are doing at TDC on power stroke overlap to read I'd the timing on this cam is off before I tear the cover back off and re degree it.
 
Before you start tearing it apart I would verify the timing mark. You can take an old spark plug and build a piston stop. You rotate engine one way until it hits stop mark damper and rotate opposite until it hits stop. The factory mark should be in the middle. If not remark the damper so you know where TDC is.
 
What's the best way to make a stop with an old plug? Gut an old plug and? I'm 99 percent positive it is correct. Ill triple verify everything again before I tear into it. Just a real drag to do it again
 
Bad Sport beat me to it. Thanks Bad Sport Pic is worth thousand words. Bill
 
Nice! Thanks guys. What's that center piece from looks familiar but I can't put my finger on it.
 
gtmopar said:
Will the power valve effect the idling? It's been a long time since I've messed with a Holley, all my last carbs were Eddys which were pretty straight forward yet not very tunable. I'm wondering if the idle circuit on the metering block is plugged? I rebuilt that carb about a year ago and I ran it on another motor for a short period then pulled it off and it sat. It may have gotten some crap in it so I'll pull it apart and inspect it before I buy a new one.
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Power Valve can definitley affect idle quality. Especially if it's blown out(usually happens if it backfires through the carb. Only takes 1 time if it's bad enough). Also if it's not the right calibration for the motor & it's opening up too soon due to lower vacuum. Obviously you want to check timing & verify the marks like others have suggested as well.
 
Lonewolf3165 said:
Power Valve can definitley affect idle quality. Especially if it's blown out(usually happens if it backfires through the carb. Only takes 1 time if it's bad enough). Also if it's not the right calibration for the motor & it's opening up too soon due to lower vacuum. Obviously you want to check timing & verify the marks like others have suggested as well.
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^^^^^^^^ X2

your eyes burning will be the give-away..
 
You cannot really check cam timing on "spit overlap" because most modern cams "are not." You'd be much better off checking balancer degrees on no1 intake opening, which will be somewhat BTC, just like timing


That is, get the cam card and pick something like intake opening, get your TDC checked (above mentioned piston stop......one of my favorite things to check.)

Then either get degree tape or otherwise mark the balancer. You can "rig" an indicator for a little more accuracy right on the valve, but this ought'a tell you if it's within 4* or so
 
gtmopar said:
Carter comp- no power valve.
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gtmopar said:
The carb is an older 750 DP that I rebuilt but either I'm losing my touch or this carb is ready for retirement. .
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then read posts 19 thru 25,, which resulted in Lonewolf's and my response...

because it'll idle rich as he//, with a blown P/V..

cheers

I know the carb has been changed.. thnx..
 
gtmopar said:
Carter comp- no power valve.
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I thought I read in an earlier post you had a Holley 750 DP on it & asked if the power valve could cause a problem at idle. If I'm wrong forgive me.
I hope you get it sorted out soon. Things like this can really bug the hell outta you.
 
It had a holley initially which I was having issues with and I swapped it out with a freshly rebuilt carter. I had swapped out the power valve but to no avail. I'm leaning heavily towards cam timing. This does not act like a lean/rich condition it sounds like a sequence is out which is leaning me further towards cam timing issue. I'm just burnt out and ready for these big issues to be gone.
 
before you go much further the pick up on the dizzy might be wired backwards. I fought this exact problem with mine.different years were wired differently.i cut the wires and reversed them and timing worked perfect.before couldn't get it below like 20 deg.
 
Thanks bd guess I could swap the wires on the coil and give it a shot. Thanks bud. I'm willing to travel the path of least resistance work wise.
 
bdusted440 said:
before you go much further the pick up on the dizzy might be wired backwards. I fought this exact problem with mine.different years were wired differently.i cut the wires and reversed them and timing worked perfect.before couldn't get it below like 20 deg.
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They were not changed on different years. If the polarity is wrong it's because the pickup was built wrong AKA defective, but this does and has happened

gtmopar said:
Thanks bd guess I could swap the wires on the coil and give it a shot. Thanks bud. I'm willing to travel the path of least resistance work wise.
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He's not talking about coil wires. He's talking about the two distributor pickup coil wires. Reversing them moves spark timing in relation to the distributor rotor, IE "rotor phasing."
 
67Dart273 said:
They were not changed on different years. If the polarity is wrong it's because the pickup was built wrong AKA defective, but this does and has happened



He's not talking about coil wires. He's talking about the two distributor pickup coil wires. Reversing them moves spark timing in relation to the distributor rotor, IE "rotor phasing."
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right 67dart273
 
Da mn rick you built the engine right? Needd to hear this thing run
 
Yes I built the engine right!!! Lol! Verified cam timing again today and I'm right on the money at 106 centerline. Even called my cam grinder to verify everything, verified valve overlap on power stroke and it was how it should be. Just ordered an MSD digital E curve so damn it she will run!! Tired of dicking with stuff that I thought might be questionable to begin with.
 
How you doing mike? I'm so ready to slap some slicks on and beat on it like it owes me money! Guess it's getting s little late in the season to hit up Infineon.
 
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