Engine Rebuild Issue
Thread Starter
Intermediate
Joined: May 2013
Posts: 47
Likes: 0
Engine Rebuild Issue
Alright so I have a 1969 Coupe with a matching numbers 350 in it.
The car was passed down to me from my father not to long ago and i've been restoring in the last year or so in his memory ! It's been a great project but without him around I have had a couple of problems figuring out certain things. The engine was rebuilt a while ago ( my mom cannot even remember when ) and so when I was doing the points and timing I could not set it properly. It would run bad and choppy when at stock specifications, even when I adjusted the carb. When I set it far advanced above TDC, it worked A LOT better. My friends father said that when he had cams in one of his cars back in the day, he had to do timing similar.
I know I sound like an beginner ( but I am ) and so whats the difference of how the 350 would be stock and how it would be with "cams" I am confused on this because I guess I had a different idea of what cakes were. anyone have an opinion on this ? is this a common thing that was done to rebuilt 350's?
The car was passed down to me from my father not to long ago and i've been restoring in the last year or so in his memory ! It's been a great project but without him around I have had a couple of problems figuring out certain things. The engine was rebuilt a while ago ( my mom cannot even remember when ) and so when I was doing the points and timing I could not set it properly. It would run bad and choppy when at stock specifications, even when I adjusted the carb. When I set it far advanced above TDC, it worked A LOT better. My friends father said that when he had cams in one of his cars back in the day, he had to do timing similar.
I know I sound like an beginner ( but I am ) and so whats the difference of how the 350 would be stock and how it would be with "cams" I am confused on this because I guess I had a different idea of what cakes were. anyone have an opinion on this ? is this a common thing that was done to rebuilt 350's?
Thread Starter
Intermediate
Joined: May 2013
Posts: 47
Likes: 0
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Pulling a valve cover and putting a gauge on there to measure the lift will give you a good idea if it's a hot cam. With that said, I'm more concerned with the timing mark being off on the homonic balancer. If it's the old original, it probably slipped a little and now the marks are useless. So turn it until it runs it's best for now. As you build knowledge this stuff will be easier to explain.
If it's a hot cam, your idle will be around 800-900 rpm, maybe higher if you have a manual trans. Good luck and there is no stupid questions on here but most of us would like to see you get the manual out
If it's a hot cam, your idle will be around 800-900 rpm, maybe higher if you have a manual trans. Good luck and there is no stupid questions on here but most of us would like to see you get the manual out
Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
all cars have a cam... some more than one.... but our 350's have only 1... when your friend talked about cam'ing it, what they mean is they put in a more aggressive cam with a higher lift on the valves and a longer duration... you need to move the #1 piston to top dead center (remove spark plug drivers side front) when the piston is TDC on compression stroke, not exhaust which is 180* out (360* for a full cycle) your timing mark should be on "0" on the harmonic balancer. if it is not... it has slipped and needs to be replaced. of it is at 0, then you can start proper timing as long as you have a timing light and a 9/16 wrench to loosen the distributor.
points? throw them away and get an HEI or a Mallory unilight... imho
points? throw them away and get an HEI or a Mallory unilight... imho
Thread Starter
Intermediate
Joined: May 2013
Posts: 47
Likes: 0
Pulling a valve cover and putting a gauge on there to measure the lift will give you a good idea if it's a hot cam. With that said, I'm more concerned with the timing mark being off on the homonic balancer. If it's the old original, it probably slipped a little and now the marks are useless. So turn it until it runs it's best for now. As you build knowledge this stuff will be easier to explain.
If it's a hot cam, your idle will be around 800-900 rpm, maybe higher if you have a manual trans. Good luck and there is no stupid questions on here but most of us would like to see you get the manual out
If it's a hot cam, your idle will be around 800-900 rpm, maybe higher if you have a manual trans. Good luck and there is no stupid questions on here but most of us would like to see you get the manual out
Thread Starter
Intermediate
Joined: May 2013
Posts: 47
Likes: 0
all cars have a cam... some more than one.... but our 350's have only 1... when your friend talked about cam'ing it, what they mean is they put in a more aggressive cam with a higher lift on the valves and a longer duration... you need to move the #1 piston to top dead center (remove spark plug drivers side front) when the piston is TDC on compression stroke, not exhaust which is 180* out (360* for a full cycle) your timing mark should be on "0" on the harmonic balancer. if it is not... it has slipped and needs to be replaced. of it is at 0, then you can start proper timing as long as you have a timing light and a 9/16 wrench to loosen the distributor.
points? throw them away and get an HEI or a Mallory unilight... imho
points? throw them away and get an HEI or a Mallory unilight... imho
Is there a way to tell what kind of cam you have without taking everything ( timing cover, water pump etc.) off? and you are deffinetly right about the mark probably just being off because it was advanced at the top when it ran good !
Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
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Burning Brakes
Joined: Nov 2011
Posts: 1,170
Likes: 201
From: Willoughby Ohio
The only way to check what you have is to get a degree wheel kit.
Comp cams and Summit Racing have detailed instructions on their web sites for these kits.With these kits you can check intake centerline,valve opening and closing,lsa etc.. I believe you'll have to remove some components as you previously stated.I guess you'll have to decide if it is
worth the effort.
Comp cams and Summit Racing have detailed instructions on their web sites for these kits.With these kits you can check intake centerline,valve opening and closing,lsa etc.. I believe you'll have to remove some components as you previously stated.I guess you'll have to decide if it is
worth the effort.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
Alright so I have a 1969 Coupe with a matching numbers 350 in it.
The car was passed down to me from my father not to long ago and i've been restoring in the last year or so in his memory ! It's been a great project but without him around I have had a couple of problems figuring out certain things. The engine was rebuilt a while ago ( my mom cannot even remember when ) and so when I was doing the points and timing I could not set it properly. It would run bad and choppy when at stock specifications, even when I adjusted the carb. When I set it far advanced above TDC, it worked A LOT better. My friends father said that when he had cams in one of his cars back in the day, he had to do timing similar.
I know I sound like an beginner ( but I am ) and so whats the difference of how the 350 would be stock and how it would be with "cams" I am confused on this because I guess I had a different idea of what cakes were. anyone have an opinion on this ? is this a common thing that was done to rebuilt 350's?
The car was passed down to me from my father not to long ago and i've been restoring in the last year or so in his memory ! It's been a great project but without him around I have had a couple of problems figuring out certain things. The engine was rebuilt a while ago ( my mom cannot even remember when ) and so when I was doing the points and timing I could not set it properly. It would run bad and choppy when at stock specifications, even when I adjusted the carb. When I set it far advanced above TDC, it worked A LOT better. My friends father said that when he had cams in one of his cars back in the day, he had to do timing similar.
I know I sound like an beginner ( but I am ) and so whats the difference of how the 350 would be stock and how it would be with "cams" I am confused on this because I guess I had a different idea of what cakes were. anyone have an opinion on this ? is this a common thing that was done to rebuilt 350's?
Do a search on this subject you'll find what you're looking for.
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 493
From: Salmon Arm, BC
You should post where you live, someone may live close by and can come over and help you. It's hard to diagnois a problem when the person doesn't know the basics. (No offence meant to you at all)
Guys here really like to help.....
Guys here really like to help.....
