Trouble setting timing
Thread Starter
Racer
Joined: May 2007
Posts: 296
Likes: 4
From: London Ontario
Yes the 5psi was a typo its 5 inHg. I have checked the balancer, which is new and the marks line up. I have double checked the firing order and it is correct unless comp changed the order on their cam. I did a compression check to be safe and all cylinders are 160-180 psi
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
Alright, Curtis, I think your next step needs to be to make sure that the timing mark lines up with tdc on the compression stroke of cylinder #1. If you are not sure how to do this, or have already done it, let us know.
Scott
Thread Starter
Racer
Joined: May 2007
Posts: 296
Likes: 4
From: London Ontario
I checked that the timing marks line up, with a screwdriver in the spark plug hole. It seemed to line up. I also checked cam timing which showed to be 4 degrees advanced which is pretty common. I have a manual trans so there aren't any vac. lines running back there. I've pretty much run out of ideas, I'm sure it will be some stupid little thing.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
I checked that the timing marks line up, with a screwdriver in the spark plug hole. It seemed to line up. I also checked cam timing which showed to be 4 degrees advanced which is pretty common. I have a manual trans so there aren't any vac. lines running back there. I've pretty much run out of ideas, I'm sure it will be some stupid little thing.
You said in your first post that the carb is running rich. What is it that makes you think that? In an earlier post I mentioned that 5" of vacuum is less than the 6.5 that would open a typical stock power valve, but disregard that, the power valve has no effect on the idle circuit.
Scott
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
Scott
Melting Slicks
Joined: May 2009
Posts: 3,079
Likes: 315
2024 C3 of the Year Finalist - Unmodified
Hey, even the experts can get it wrong. I remember on the engine dyno prior to firing my rebuilt engine for the first time, the operator asked my rebuilder if he got the distributor in right. His answer was "well if I didn't, it could only be 180 degrees off." 
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Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
If you are running the stock intake with the smiley face the stainless baffle is a must,otherwise you have an open vacuum path to the exhaust heat riser crossover which will upset your carb and cause a rich condition.
Burning Brakes
Joined: May 2008
Posts: 1,116
Likes: 5
From: Middleburg Florida
I was having similar issues, seemed like I need alot of initial timing, unstable idle when I put it in gear, all kinds of things. At 800 rpm I was pulling about 8 inches of vacuum. Then found that Lars had posted a paper on timing. It helped me check my centrifugal and vacuum advance. After following the procedure he spelled out I found my vacuum can wasn't right for my application. Since I've changed it, the engine runs and idles much better. Unfortunatley, I don't have the link for the paper, all I have is a printed copy in my garage, but maybe someone here does, our a search would find it for you.
Thread Starter
Racer
Joined: May 2007
Posts: 296
Likes: 4
From: London Ontario
PROBLEM SOLVED,
Turns out the Ebay distributor was bad. It currently has my distributor out of my 75 (so no tach) but it seems to run great, so glad its finally working. Thanks for all the help.
Turns out the Ebay distributor was bad. It currently has my distributor out of my 75 (so no tach) but it seems to run great, so glad its finally working. Thanks for all the help.
