http://www.forabodiesonly.com/mopar/showthread.php?t=328913
This sounds similar to what 318willrun had.
This sounds similar to what 318willrun had.
PUZZLER!!! My new motors a dog! what did I miss?
- Thread starter mbaird
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67Dart273
Well-Known Member
I agree but got lost here. Did you ever actually check that the balancer is accurate? (piston stop, etc)
Have you set idle timing by "peaking" on vacuum reading?
I agree completely. Springs are new Hughes matched to specs for the 403 cam...
Yes I checked balancser..it's was off by 5 degrees
Have not timed to vacuum but my brother suggested that.
I will get on it tomorrow and sunday I
nm9stheham
Well-Known Member
Ahah,,, you did not use the proper ' break-in additive'... LOL
it should fry the tires , and get decent mpg with that combo , cyl pressure is low for a new build .
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Before you take the front off, I highly recommend you re-prove the balancerTDC, cuz 5* seems to be a lot for it to be off. If it really is that far off, maybe it needs to be replaced. Of course after the cover comes off, and before you begin the degreeing process, you will need to find true TDC again.
I hope you didn't use the snout bolt to turn the engine during degreeing. This may work with the heads off, but once the valve springs are involved, all bets are off. Also be sure you are degreeing off the lifter body.This is a very tiny target to successfully hit. I made a slug to fit in the lifter bore, with a big head to hit. The dial indicator(DI) plunger needs to remain on the spot,on the slug,where you put it. That is to say, the axis of the DI plunger needs to be parallel to the axis of the lifter bore. They don't need to be concentric, parallel is good. If the plunger scrubs sideways across the slug as the slug rises, then it will not be measuring accurately. It will lose some lift. Fortunately it loses the same amount going down, so its not super-critical.
They make a crank turner. I think I've seen them at Jegs.
Some guys say to turn the lifter upside down. But I suggest that that is a no-no, cuz the base of the lifter, which you will now be measuring off, is anything but flat.You also cannot use the pushrod cup. Some have welded a stick onto or into an old lifter, to bring the measuring surface up to the deck. Well is the base of that lifter FLAT? That could work if the base is flat. I like my slug. But I can't use it once the intake is on, the slug just won't pass through the inspection tunnels.
I hope you didn't use the snout bolt to turn the engine during degreeing. This may work with the heads off, but once the valve springs are involved, all bets are off. Also be sure you are degreeing off the lifter body.This is a very tiny target to successfully hit. I made a slug to fit in the lifter bore, with a big head to hit. The dial indicator(DI) plunger needs to remain on the spot,on the slug,where you put it. That is to say, the axis of the DI plunger needs to be parallel to the axis of the lifter bore. They don't need to be concentric, parallel is good. If the plunger scrubs sideways across the slug as the slug rises, then it will not be measuring accurately. It will lose some lift. Fortunately it loses the same amount going down, so its not super-critical.
They make a crank turner. I think I've seen them at Jegs.
Some guys say to turn the lifter upside down. But I suggest that that is a no-no, cuz the base of the lifter, which you will now be measuring off, is anything but flat.You also cannot use the pushrod cup. Some have welded a stick onto or into an old lifter, to bring the measuring surface up to the deck. Well is the base of that lifter FLAT? That could work if the base is flat. I like my slug. But I can't use it once the intake is on, the slug just won't pass through the inspection tunnels.
Holley > edelbrock in terms of carburetion... Think the rest of the guys are spot on here with checking the timing both at the balancer and if that checks out time to pull the front cover and see whats up with the cam timing.
MopaR&D
Nerd Member
You mentioned having an 'orange box' in the OP those are notorious for not being reliable, maybe try a different ignition box?
Your combo should run great it's definitely either tuning or a bad part somewhere.
Your combo should run great it's definitely either tuning or a bad part somewhere.
cam timing, too far advanced, that's what I'm stick'n to.
67Dart273
Well-Known Member
Plus you can check the cam degree without tearing the timing cover off
OP: Tell us just how you checked the TDC mark. In my book there are only two ways, essentially.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Yeah that's true; to check the cam timing, the cover can stay on. I guess I jumped ahead a tad far just there.
Also for a quick-check, you don't need a dial indicator either.......you just need to find split overlap at or near TDC/exhaust stroke. If it's within 4 or 5 degrees,either way, the timing is good enough to not cause these kinds of problems.And,although I've never tried it, I believe that it could be done by just removing a valvecover.You would, however, have to make a tool.
Also for a quick-check, you don't need a dial indicator either.......you just need to find split overlap at or near TDC/exhaust stroke. If it's within 4 or 5 degrees,either way, the timing is good enough to not cause these kinds of problems.And,although I've never tried it, I believe that it could be done by just removing a valvecover.You would, however, have to make a tool.
64physhy
Well-Known Member
Check out this thread:
http://www.forabodiesonly.com/mopar/showthread.php?t=328913&page=4
He had similar problems. Pics of the problem are on posts 79 and 81. He lined up the dot for the keyway instead of the dot on the tooth. He's not the first to do that.
http://www.forabodiesonly.com/mopar/showthread.php?t=328913&page=4
He had similar problems. Pics of the problem are on posts 79 and 81. He lined up the dot for the keyway instead of the dot on the tooth. He's not the first to do that.
fishy68
Tyr Fryr's Inc.
I wonder if the cam was improperly ground. Like others have said that should be a torquey bugger that'd easily smoke the tires. I'd degree the exhaust lobe also to see if the cam was ground right. It's rare to get a bad cam but it happens and the lower than normal cranking compression indicates something isn't quite right and a screwed up cam could do that
T56MaxTorq
Well-Known Member
I've done this by mistake and it cause all kinds of havoc! cam timing was way off and although she did run, she had no power and wouldn't get above 30. Also sounded like a diesel.
Pull that cover off and triple check the timing with a piston stop and a degree wheel. Cams can be ground improperly as well.
Inertia
Well-Known Member
^^^^ Xs2
I've always checked for a jumped chain by bring #1 or #6 valves into overlap,, check the TDC mark,, less than 8* (allowing for stretch) is good to go,, over 12* past TDC,, and It's coming apart.
But it was brought to my attn that with a radical split overlap cam,, my way could be wrong,,, but I haven't found that big a split overlap cam yet.. lol
cheers
oliver
Well-Known Member
advanced will increase cylinder pressure, im going with cam being retarded.
The 12 to 12 is just so you install the distributor on the power stroke. The first stroke is the intake, the next is the compression, then the power. If you line them up dot to dot and stab the distributor it will be 180 degrees out because your on the intake stroke when its dot to dot.
My two cents is that the cam timing is off some how. Be it a tooth off or if the crank gear has 4 degrees advanced or retarded and you mistakenly set it on that.
what's the verdict.
tarvin890
tarvin890
i thought there was just a thread like this and it turned out to be the timing chain was waaaayyy off...
I have it all apart and ready to check timing...work and gf and hockey and dirtbiking and family keep getting in the way. Will get her buttoned up this evening.
I ordered the HEI conversion just in case it turns out to be a faulty control box.(I don't think so but...)
I also ordered a Moroso 18" degree wheel only to figure out that I have a Depth Perception problem...Its really big!!. "Apperhently I do not have 12 inches! ". Lol....
I ordered the HEI conversion just in case it turns out to be a faulty control box.(I don't think so but...)
I also ordered a Moroso 18" degree wheel only to figure out that I have a Depth Perception problem...Its really big!!. "Apperhently I do not have 12 inches! ". Lol....
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