Lets talk timing..
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Le Mans Master
Joined: Sep 2000
Posts: 9,078
Likes: 7
From: DFW TX
Cruise-In VII Veteran
St. Jude Donor '07
Lets talk timing..
For the first time I checked my timing. It was set at about 15+ degrees retarded. Put it at 4 degrees advanced and the idle bumped up to about 1000 rpm's pluged in vacuum advance rev'ed it. It advanced to about 20 and started missing bad. 
Am I the victim of a misaligned timing gear sprocket?
I also have a small miss at 2000 rpm. It's not bad, but annoying when driving at cruise speed. I suspect a manifold leak and will trouble shoot that later. The car was tuned with multiple vacuum leaks with I bought it.
This is a mild 350 with a comp 268 cam and Edelbrock manifold/cab.
Am I the victim of a misaligned timing gear sprocket? I also have a small miss at 2000 rpm. It's not bad, but annoying when driving at cruise speed. I suspect a manifold leak and will trouble shoot that later. The car was tuned with multiple vacuum leaks with I bought it.
This is a mild 350 with a comp 268 cam and Edelbrock manifold/cab.
Pro
Joined: Apr 2007
Posts: 736
Likes: 1
From: Chester VA
Don't bother with any further timing changes until the vac leaks are fixed. The car will want to rev high with the leaks, they probably timed it retarded so it would idle under 1000, also will need to adjust the carb since it'll richen up after the leaks are fixed.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
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From: Boca Raton Florida
If you suspect the valve timing to be off your going to need to pull the left valve cover and bring #1 to TDC and make sure the valves are closed. Or, just bite the bullet and pull the timing chain cover
Race Director
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I'm questioning the balancer or the wrong timing tab. 15* retarded would run terrible, overheat etc. Someone probably tuned it by ear to run OK. It was running Ok right?
Bring to TDC and check timing marks. Use a small screw driver inserted in plug hole and roll motor over by hand. You can feel when piston nears the top and as it *rocks* at TDC. That will be close enough to see what's up.
JIM
Bring to TDC and check timing marks. Use a small screw driver inserted in plug hole and roll motor over by hand. You can feel when piston nears the top and as it *rocks* at TDC. That will be close enough to see what's up.
JIM
Thread Starter
Le Mans Master
Joined: Sep 2000
Posts: 9,078
Likes: 7
From: DFW TX
Cruise-In VII Veteran
St. Jude Donor '07
Before I jacked with it. It had a small miss above 1500 that would disappear as you would increase the throttle.
This is definely a mismatched motor, so it is not unlikely it has a late model balancer on an older cover. The cover looks like an original 68. Timing marks start at 2 degrees and increase to 12. No TDC.
I'm going to look for the vacuum leak tomorrow. Any ideas what to use. We use to use propane back in the day.
This is definely a mismatched motor, so it is not unlikely it has a late model balancer on an older cover. The cover looks like an original 68. Timing marks start at 2 degrees and increase to 12. No TDC.
I'm going to look for the vacuum leak tomorrow. Any ideas what to use. We use to use propane back in the day.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
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2017 C2 of Year Finalist
Carb cleaner works OK. Just shield carb from sucking it in and making you chase ghosts.
JIM
JIM
