Adjustable Timing Pointer
Thread Starter
Race Director
Joined: Feb 1999
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Adjustable Timing Pointer
I just finished up installing a new set of Harland Sharpe Roller Rockers and an Edlebrock RPM Airgap. While I was at it, I set the end play on my distributor and replaced the limit bushing for the centrifugal advace. Now that I have it all back together and running I was setting my timing. I have it set at 36 degrees all in by 3000 RPM by using a combination of a light and a medium spring. Total with vaccum advance is around 52 degrees. This is all according to my dial back timing light and my Tavia adjustable timing pointer.
Here is where my question comes in, is there a way I can verify my pointer is setting where it should be and has not moved?
Thanks for any help you can offer.
Eddie
Here is where my question comes in, is there a way I can verify my pointer is setting where it should be and has not moved?
Thanks for any help you can offer.
Eddie
Thread Starter
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Joined: Feb 1999
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Originally Posted by David Ey
You can poke something in the sparkplug hole and rotate crank slowly by hand and feel for tdc. They make a tool for this.
I was thinking of pulling the plugs and getting a bolt of the correct thread and using that as a stop. Rotate the motor one direction till it comes to the stop. Mark the balancer. Rotate the motor in the other direction and mark the balancer. Remove the bolt and got to a point halfway between the two marks and this should be where I need to put my pointer on Zero.
Does this sound correct? All I need to know is what size bolt to come up with. Is that a 1/2 thread?
Thread Starter
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Joined: Feb 1999
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Originally Posted by bobs77vet
i like ths idea of really long stiff rubber hoses....sticking bolts in there makes me nervous
I am with you on that one also Bob. That is why I was thinking of removing all of the plugs so I could have a little more control of the motor while I was rotating it. Splain a little more about your rubber hose idea, I may like it better.
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Le Mans Master
Joined: Jan 2006
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From: Boca Raton Florida
Sticking a bolt in there (or anything of size and hardness) is a bad idea. Use a thin plastic stick and carefully rotate the engine by hand to get#1 to TDC, It should be at 0 according to the mark on the balancer and the marker.
Le Mans Master
Joined: Jan 2006
Posts: 8,319
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From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
hmmmm
I wouldnt go sticking anything hard in my cylender either, to many opprtuinities for gremlins or murphy to raise their ugly heads!!!!
This can also be done effectively with a good piece of rope. Rotate the motor one direction till it comes to a stop. Mark the balancer. Rotate the motor in the other direction and mark the balancer. Remove the bolt and got to a point halfway between the two marks and this should be where I need to put my pointer on Zero.
The eastwood comapny sells a neat tool that does the job well. its a whistle that stops blowing when the piston is at TBD 22 bucks a keeper for the tool box.
http://www.eastwoodco.com/shopping/p...=1&keyword=TDC
tim
This can also be done effectively with a good piece of rope. Rotate the motor one direction till it comes to a stop. Mark the balancer. Rotate the motor in the other direction and mark the balancer. Remove the bolt and got to a point halfway between the two marks and this should be where I need to put my pointer on Zero.
The eastwood comapny sells a neat tool that does the job well. its a whistle that stops blowing when the piston is at TBD 22 bucks a keeper for the tool box.
http://www.eastwoodco.com/shopping/p...=1&keyword=TDC
tim
Last edited by sweethence; Feb 1, 2006 at 08:11 AM.
Racer
Joined: Dec 2003
Posts: 304
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From: Pasadena Maryland
I have a whistle that I purchased from Eastwood for 10 Bucks. Screw it in place of the spark plug (has multiple adapters) rotate engine ( I use long bolts in the crank pulley with a breaker bar) and when the whistle stops you're at TDC. I use it for setting my rockers as well. Never lets me down.
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Originally Posted by Eddie 70
I was thinking of pulling the plugs and getting a bolt of the correct thread and using that as a stop. Rotate the motor one direction till it comes to the stop. Mark the balancer. Rotate the motor in the other direction and mark the balancer. Remove the bolt and got to a point halfway between the two marks and this should be where I need to put my pointer on Zero.
Does this sound correct? All I need to know is what size bolt to come up with. Is that a 1/2 thread?
Does this sound correct? All I need to know is what size bolt to come up with. Is that a 1/2 thread?
http://www.jegs.com/webapp/wcs/store...tegoryId=23395
BigBlockk
Later.....
Tech Contributor
Joined: Aug 1999
Posts: 14,373
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From: At my Bar drinking and wrenching in Lafayette Colorado
You can't use a soft stop like rope, plastic, rubber, or a whistle to determine TDC within the tolerance needed for setting up a timing tab. You have to use a hard stop like a bolt or the TDC indicator shown by BigBlockk (which is just an adjustable bolt). A hard stop will not do any damage to the engine/piston as long as it has been deburred and does not have a sharp edge/corner, and as long as you show reasonable care in the amount of force you use when running the piston up against the stop. You have to get repeatable data within 1 degree when setting up a tab, and you can't repeat within 1 using a compressable or cushioned stop system.
Thread Starter
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Originally Posted by BigBlockk
This is the preferred method for finding TDC on an engine that has the heads installed. You do this when degreeing a cam or timing the ignition. Here is the tool to use.
http://www.jegs.com/webapp/wcs/store...tegoryId=23395
BigBlockk
Later.....
http://www.jegs.com/webapp/wcs/store...tegoryId=23395
BigBlockk
Later.....
Cool tool. I guess I will order one of those to make the job just a little less painful.
Melting Slicks
Joined: Jun 2003
Posts: 2,802
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From: Niles, MI
Don't buy the POS from Jegs or Summit. I bought one and the threads were so screwed up I couldn't screw it into the spark plug hole. I got one from Crane Cams. Works like a charm.
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
Originally Posted by Kid Vette
Don't buy the POS from Jegs or Summit. I bought one and the threads were so screwed up I couldn't screw it into the spark plug hole. I got one from Crane Cams. Works like a charm.
I got one of those with a cam degree kit and it didn't fit the threads either. I used a straw to find the piston at TDC. McDonalds has those big fat sturdy ones.
Thread Starter
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Originally Posted by Kid Vette
Don't buy the POS from Jegs or Summit. I bought one and the threads were so screwed up I couldn't screw it into the spark plug hole. I got one from Crane Cams. Works like a charm.
Mark, Kidvette, thanks for the link. I just ordered the Crane piston stop from Summit. Should be here Wednesday.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Okay, here is what I have found out using the stop so far. Right now going in the correct direction of rotation I am 0 degrees TDC. In the opposite direction or rotation I am at 8 degrees TDC. I guess it is correct to assume that I need to remove the stop, move the engine to 4 degrees TDC and put then align the pointer to this point. This should be Zero TDC from now on.
I am going to fly into it thinking this anyway.
Someone correct me if I am wrong.
I am going to fly into it thinking this anyway.
Someone correct me if I am wrong.