Engine run with timing 180* off?
#1
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Car: 2007 Corvette Z06
Engine: LS7
Transmission: 6 speed
Engine run with timing 180* off?
Will the engine fire with the cam timing 180* off (dist set on exhaust stroke)? Also where does the connector for the temp sensor? from the EGR valve (that single wire) go to? I can't seem to find where it hooks to the wiring harness.
I would really love my car to run again after all the work of a cam swap and a few other things. I seem to have spark and timing is set at ~3,4*, fuel pressure is ~48 psi, but car won't fire up at all.
13's are coming...
I would really love my car to run again after all the work of a cam swap and a few other things. I seem to have spark and timing is set at ~3,4*, fuel pressure is ~48 psi, but car won't fire up at all.
13's are coming...
#2
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You must be referring to distributor in 180* out? Or did you install the cam 180 out?.
I could be wrong, but would think that if you had the cam in 180 out, but then rotated the crank a full rev, then only the distributor would be out..which could be easily corrected.
One thing to keep in mind, there's no way you can estimate the ignition timing if the engine is not running...ignition timing is specified at engine RPMs, not static. maybe on the old flathead engines with the timing plug on top of #1, but not on the SBC
I could be wrong, but would think that if you had the cam in 180 out, but then rotated the crank a full rev, then only the distributor would be out..which could be easily corrected.
One thing to keep in mind, there's no way you can estimate the ignition timing if the engine is not running...ignition timing is specified at engine RPMs, not static. maybe on the old flathead engines with the timing plug on top of #1, but not on the SBC
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Car: yep
Engine: uhuh
Transmission: sure does
One thing to remember when installing cams...when you line up the dot to dot on the cam and crank gears...you are NOT on TDC #1 firing.
You are on TDC #6.
It doesnt matter how you line up the dots, either dot to dot, (12 and 6 o clock) or 12 and 12 o clock)
If you line the dots up 12 crank and 6 cam gear, so they are facing each other, you need to make one more engine revolution to drop the dist in facing #1.
If you line them up at 12 o clock crank and 12 o clock cam gear, you can drop the dist right in and line up to #1.
Are you confused yet??
You are on TDC #6.
It doesnt matter how you line up the dots, either dot to dot, (12 and 6 o clock) or 12 and 12 o clock)
If you line the dots up 12 crank and 6 cam gear, so they are facing each other, you need to make one more engine revolution to drop the dist in facing #1.
If you line them up at 12 o clock crank and 12 o clock cam gear, you can drop the dist right in and line up to #1.
Are you confused yet??
#5
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Car: 2007 Corvette Z06
Engine: LS7
Transmission: 6 speed
Alright, well the timing marks were at 6 and 12 with piston #1 at TDC for the cam. Then for the dist. I had the Harmonic balancer at 0* and both valves were closed on the #1 cylinder. I figured that should work but apparrently not. So the only thing I figure is maybe the dist is 180* off. I'll pull the #1 plug and check to make sure it's on the compression stroke today. Thanks
#6
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Car: 2007 Corvette Z06
Engine: LS7
Transmission: 6 speed
I tried putting the dist. in 180* different from what it was and still got nothing. I think before maybe have been better with an occasional "pop", now it just cranks.
Also come to think of it I put the cam in with both dots at their respective 12 o'clocks.
I think it's times to pull some more plugs out so I can turn it over easier.
Do you think it would be worth while to remove the driver's side valve cover? Definately frustrating now and considering getting it towed somewhere to make it run.
Also come to think of it I put the cam in with both dots at their respective 12 o'clocks.
I think it's times to pull some more plugs out so I can turn it over easier.
Do you think it would be worth while to remove the driver's side valve cover? Definately frustrating now and considering getting it towed somewhere to make it run.
#7
Originally posted by Beast5spdGTA
I tried putting the dist. in 180* different from what it was and still got nothing. I think before maybe have been better with an occasional "pop", now it just cranks.
Also come to think of it I put the cam in with both dots at their respective 12 o'clocks.
I think it's times to pull some more plugs out so I can turn it over easier.
Do you think it would be worth while to remove the driver's side valve cover? Definately frustrating now and considering getting it towed somewhere to make it run.
I tried putting the dist. in 180* different from what it was and still got nothing. I think before maybe have been better with an occasional "pop", now it just cranks.
Also come to think of it I put the cam in with both dots at their respective 12 o'clocks.
I think it's times to pull some more plugs out so I can turn it over easier.
Do you think it would be worth while to remove the driver's side valve cover? Definately frustrating now and considering getting it towed somewhere to make it run.
Once you're positive you've got things at TDC #1, pull your distributor cap off. If the rotor isn't lined up with the proper location (roughly) for the #1 spark plug wire nows you're chance to pull the distributor and move it around a few teeth (or 180).
This should get you up and running, provided you adjusted the lash properly.... If you're not certain go ahead and take the covers off again. You don't want to bend any valves or anything.
Good luck,
Hellraiser
[edit] just read the part of your earlier post about lining up the cam dots. might as well pull the valve cover,so you can see the rockers. [edit]
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#8
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Car: 2007 Corvette Z06
Engine: LS7
Transmission: 6 speed
Well, w/o adjusting anything from the last time and just charging my battery up (again), the car started. Timing was maybe like 12* so I set it at ~5-6*. It idles fine and drives alright right now, but definately isn't running up to my expactations, I haven't beat on it yet ,but it seems to missing some top end power(like less than with the stock cam), but pulling harder in the 2000-3500 range. Kinda feels like the engine isn't pulling smooth(like a cylinder missing maybe?). I'll try and get someone who can "feel and hear" an engine better than me to go fo a ride.
#9
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I don't want to imply any intelligence mis-haps, but you'd be suprised at how well your engine can run with plug wires swapped.
I'd go over the routing again and make sure that none are twisted up, or on the wrong plug.
I'd go over the routing again and make sure that none are twisted up, or on the wrong plug.
#10
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Car: 2007 Corvette Z06
Engine: LS7
Transmission: 6 speed
Yeah, I've been thinking about the plug wires, especially since I let a friend read off the order from the book. I'll check tomorrow.
Anyone know where the EGR valve wire connects to? It's a single wire connection.
Anyone know where the EGR valve wire connects to? It's a single wire connection.
#11
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actually the distributor WILL run 180 Degrees off, If you also change the spark plugs 180 degrees off too. Its scary, but imagine doing a cam swap, and not remembering where your rotor was. (i did this) so you figure, ok, ill just find TDC of piston 1, then put the cap on in its appropriate place... so you find TDC of #1 and look at the rotor... ok its pointing... there, so we will place the cap on like this... Viola! it runs! BUT did you know....
Just because you changed the location of the cap and rotor by installing it backwards and just because it runs DOESNT MEAN you can expect it to work the way it should... IN FACT under load your spark will break up, not to mention you may see some ODD / WEIRD timing effects when the throttle / load goes up. Ford is the same way. For some reason, i cant explain, it will run but will run like **** when this occurs. i found out the hard way. One of the ways i was able to tell was suddenly after the cam swap i was running richer than hell and fouling the hell out of plugs, i figured it was my coil gone bad or rotor not sparking strong enough, so i fouled around 16 plugs before i changed the carb just to get it to lean out a little. then i noted ALOT of TOP END POWER missing. of course, i associated it with other things, like over-stall converting the engine, or bad wires, or just overall bad engine combo. Wrong again, the distributor was in 180 Degrees off. all that trouble, because i didnt remember how it came out before the cam swap. good luck!
Just because you changed the location of the cap and rotor by installing it backwards and just because it runs DOESNT MEAN you can expect it to work the way it should... IN FACT under load your spark will break up, not to mention you may see some ODD / WEIRD timing effects when the throttle / load goes up. Ford is the same way. For some reason, i cant explain, it will run but will run like **** when this occurs. i found out the hard way. One of the ways i was able to tell was suddenly after the cam swap i was running richer than hell and fouling the hell out of plugs, i figured it was my coil gone bad or rotor not sparking strong enough, so i fouled around 16 plugs before i changed the carb just to get it to lean out a little. then i noted ALOT of TOP END POWER missing. of course, i associated it with other things, like over-stall converting the engine, or bad wires, or just overall bad engine combo. Wrong again, the distributor was in 180 Degrees off. all that trouble, because i didnt remember how it came out before the cam swap. good luck!
#12
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Car: 2007 Corvette Z06
Engine: LS7
Transmission: 6 speed
How about the number 2 spark plug wire melted to the header. It runs alot better now on 8 cylinders and I haven't fixed the wire yet, just got it off the header tube. Anyone know if the timing should be advanced more when changing to a cam with more duration?
#14
Originally posted by Beast5spdGTA
How about the number 2 spark plug wire melted to the header. It runs alot better now on 8 cylinders and I haven't fixed the wire yet, just got it off the header tube. Anyone know if the timing should be advanced more when changing to a cam with more duration?
How about the number 2 spark plug wire melted to the header. It runs alot better now on 8 cylinders and I haven't fixed the wire yet, just got it off the header tube. Anyone know if the timing should be advanced more when changing to a cam with more duration?
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