350 SBC roller cam timing.....
Thread Starter
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
350 SBC roller cam timing.....
L98 head, pass side HEI and DPFI......so upon trying to start engine, I can't seem to get the HEI timing correct.....SO how to set the pointer with the coil power going in from directly across the driver side??
the coil/connections were always at 90* off the fore/aft to the driver side.....
pulled plug many times and can NOT get the ignition timing correct.....SO]
when #1 is at TDC, just what is supposed to be the position of the rotor button?? at #1 directly or maybe at #2???
the coil/connections were always at 90* off the fore/aft to the driver side.....
pulled plug many times and can NOT get the ignition timing correct.....SO]
when #1 is at TDC, just what is supposed to be the position of the rotor button?? at #1 directly or maybe at #2???
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
actually as high as your advance past one on the leading edge of the rotor when the spark first jumps.
So when you install a dizzy and it rotates in line up number 1 plug cap wire then go past center rotor to what ever your initial advance is
Like 12 degrees just to fire the motor. Have the timing light all ready to go with the vacuum advance plugged
Look at the damper pointer for ATDC like 12 degrees if the rotor is centered on the cap pole number 1 spark plug . Then with mild tightness on the bolt you rotate the dizzy to get the right timing
Does that make sense
So when you install a dizzy and it rotates in line up number 1 plug cap wire then go past center rotor to what ever your initial advance is
Like 12 degrees just to fire the motor. Have the timing light all ready to go with the vacuum advance plugged
Look at the damper pointer for ATDC like 12 degrees if the rotor is centered on the cap pole number 1 spark plug . Then with mild tightness on the bolt you rotate the dizzy to get the right timing
Does that make sense
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Set directly at #1 when at TDC......then turn the distributor slightly counter clockwise so the rotor tang is just after the #1 terminal. This will be about 12-15 as stated above........start the engine from there.
Jebby
Jebby
Safety Car
Joined: Oct 2004
Posts: 3,926
Likes: 738
From: Youngstown Ohio
actually as high as your advance past one on the leading edge of the rotor when the spark first jumps.
So when you install a dizzy and it rotates in line up number 1 plug cap wire then go past center rotor to what ever your initial advance is
Like 12 degrees just to fire the motor. Have the timing light all ready to go with the vacuum advance plugged
Look at the damper pointer for ATDC like 12 degrees if the rotor is centered on the cap pole number 1 spark plug . Then with mild tightness on the bolt you rotate the dizzy to get the right timing
Does that make sense
So when you install a dizzy and it rotates in line up number 1 plug cap wire then go past center rotor to what ever your initial advance is
Like 12 degrees just to fire the motor. Have the timing light all ready to go with the vacuum advance plugged
Look at the damper pointer for ATDC like 12 degrees if the rotor is centered on the cap pole number 1 spark plug . Then with mild tightness on the bolt you rotate the dizzy to get the right timing
Does that make sense
Advanced
Joined: Jun 2010
Posts: 95
Likes: 77
"Even then, it struggles to get going. Once it's up to temperature, 19 degrees initial advance, and 34 degrees total, it runs strong!"
This answers your own question. IF it gives troubles dead cold and doesn't want to start, stay running or run well till it's warmed up and the engine well heat soaked.......you need a working choke.
What is happening is that with all the steps taken to cools things down the thermal efficiency is chit when first started. In other words you have an aluminum "air gap" intake without a working exhaust crossover, aluminum heads, and a carburetor without a choke. It's going to be difficult to start and keep running until things warm up some. Advancing timing is only one part of the recipe for success, you need to introduce a much richer incoming mixture on a cold start.
Case in point. For about 10 years I raced my car quite a bit and didn't have a working choke on it. It was just OK if outside temps were pretty warm, and not bad at all on hot/humid summer days, would fire right up, only die once or twice and then I'd have to sit there and "feather" the throttle to keep it running for 2-3 minutes till it got enough heat in the engine to idle on it's own.
In the colder months it was nothing but royal PITA to get started and keep running, ENDLESS pumping the throttle to introduce enough fuel just to get a burp out of it.....very frustrating for use. As hard as it was to start and keep running still FLAWLESS once everything heated up. I drove and raced the car with a 4781-2 Holley 850 and my 1977 Q-jet and it was the same with either carb.
About 10 years ago I decided to drive the car more on the street so I put the factory intake back in place (had been running an Edelbrock RPM), Electric Choke back on the Q-jet, quieter mufflers and full length 2.5" mandrel bent tail pipes. Pump the throttle once or twice and it lighted off INSTANTLY, stayed on the fast idle till warmed up, and idled down nicely when I "blipped" the throttle to get it off the fast idle. Just for kicks I started it once in January when the outside temps were -10 degrees and it roared to life instantly. It did stall out once, but stayed running on the second try.
Now the best part. I wondered over to our local 1/8th mile track and guess what......the car picked up in 60' and 1/8 mile times with the factory parts! Also keep in mind when you read this that the engine is 455 CID and makes over 550hp.......FWIW.......
This answers your own question. IF it gives troubles dead cold and doesn't want to start, stay running or run well till it's warmed up and the engine well heat soaked.......you need a working choke.
What is happening is that with all the steps taken to cools things down the thermal efficiency is chit when first started. In other words you have an aluminum "air gap" intake without a working exhaust crossover, aluminum heads, and a carburetor without a choke. It's going to be difficult to start and keep running until things warm up some. Advancing timing is only one part of the recipe for success, you need to introduce a much richer incoming mixture on a cold start.
Case in point. For about 10 years I raced my car quite a bit and didn't have a working choke on it. It was just OK if outside temps were pretty warm, and not bad at all on hot/humid summer days, would fire right up, only die once or twice and then I'd have to sit there and "feather" the throttle to keep it running for 2-3 minutes till it got enough heat in the engine to idle on it's own.
In the colder months it was nothing but royal PITA to get started and keep running, ENDLESS pumping the throttle to introduce enough fuel just to get a burp out of it.....very frustrating for use. As hard as it was to start and keep running still FLAWLESS once everything heated up. I drove and raced the car with a 4781-2 Holley 850 and my 1977 Q-jet and it was the same with either carb.
About 10 years ago I decided to drive the car more on the street so I put the factory intake back in place (had been running an Edelbrock RPM), Electric Choke back on the Q-jet, quieter mufflers and full length 2.5" mandrel bent tail pipes. Pump the throttle once or twice and it lighted off INSTANTLY, stayed on the fast idle till warmed up, and idled down nicely when I "blipped" the throttle to get it off the fast idle. Just for kicks I started it once in January when the outside temps were -10 degrees and it roared to life instantly. It did stall out once, but stayed running on the second try.
Now the best part. I wondered over to our local 1/8th mile track and guess what......the car picked up in 60' and 1/8 mile times with the factory parts! Also keep in mind when you read this that the engine is 455 CID and makes over 550hp.......FWIW.......
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
"Even then, it struggles to get going. Once it's up to temperature, 19 degrees initial advance, and 34 degrees total, it runs strong!"
This answers your own question. IF it gives troubles dead cold and doesn't want to start, stay running or run well till it's warmed up and the engine well heat soaked.......you need a working choke.
What is happening is that with all the steps taken to cools things down the thermal efficiency is chit when first started. In other words you have an aluminum "air gap" intake without a working exhaust crossover, aluminum heads, and a carburetor without a choke. It's going to be difficult to start and keep running until things warm up some. Advancing timing is only one part of the recipe for success, you need to introduce a much richer incoming mixture on a cold start.
Case in point. For about 10 years I raced my car quite a bit and didn't have a working choke on it. It was just OK if outside temps were pretty warm, and not bad at all on hot/humid summer days, would fire right up, only die once or twice and then I'd have to sit there and "feather" the throttle to keep it running for 2-3 minutes till it got enough heat in the engine to idle on it's own.
In the colder months it was nothing but royal PITA to get started and keep running, ENDLESS pumping the throttle to introduce enough fuel just to get a burp out of it.....very frustrating for use. As hard as it was to start and keep running still FLAWLESS once everything heated up. I drove and raced the car with a 4781-2 Holley 850 and my 1977 Q-jet and it was the same with either carb.
About 10 years ago I decided to drive the car more on the street so I put the factory intake back in place (had been running an Edelbrock RPM), Electric Choke back on the Q-jet, quieter mufflers and full length 2.5" mandrel bent tail pipes. Pump the throttle once or twice and it lighted off INSTANTLY, stayed on the fast idle till warmed up, and idled down nicely when I "blipped" the throttle to get it off the fast idle. Just for kicks I started it once in January when the outside temps were -10 degrees and it roared to life instantly. It did stall out once, but stayed running on the second try.
Now the best part. I wondered over to our local 1/8th mile track and guess what......the car picked up in 60' and 1/8 mile times with the factory parts! Also keep in mind when you read this that the engine is 455 CID and makes over 550hp.......FWIW.......
This answers your own question. IF it gives troubles dead cold and doesn't want to start, stay running or run well till it's warmed up and the engine well heat soaked.......you need a working choke.
What is happening is that with all the steps taken to cools things down the thermal efficiency is chit when first started. In other words you have an aluminum "air gap" intake without a working exhaust crossover, aluminum heads, and a carburetor without a choke. It's going to be difficult to start and keep running until things warm up some. Advancing timing is only one part of the recipe for success, you need to introduce a much richer incoming mixture on a cold start.
Case in point. For about 10 years I raced my car quite a bit and didn't have a working choke on it. It was just OK if outside temps were pretty warm, and not bad at all on hot/humid summer days, would fire right up, only die once or twice and then I'd have to sit there and "feather" the throttle to keep it running for 2-3 minutes till it got enough heat in the engine to idle on it's own.
In the colder months it was nothing but royal PITA to get started and keep running, ENDLESS pumping the throttle to introduce enough fuel just to get a burp out of it.....very frustrating for use. As hard as it was to start and keep running still FLAWLESS once everything heated up. I drove and raced the car with a 4781-2 Holley 850 and my 1977 Q-jet and it was the same with either carb.
About 10 years ago I decided to drive the car more on the street so I put the factory intake back in place (had been running an Edelbrock RPM), Electric Choke back on the Q-jet, quieter mufflers and full length 2.5" mandrel bent tail pipes. Pump the throttle once or twice and it lighted off INSTANTLY, stayed on the fast idle till warmed up, and idled down nicely when I "blipped" the throttle to get it off the fast idle. Just for kicks I started it once in January when the outside temps were -10 degrees and it roared to life instantly. It did stall out once, but stayed running on the second try.
Now the best part. I wondered over to our local 1/8th mile track and guess what......the car picked up in 60' and 1/8 mile times with the factory parts! Also keep in mind when you read this that the engine is 455 CID and makes over 550hp.......FWIW.......
Jebby
Advanced
Joined: Jun 2010
Posts: 95
Likes: 77
Don't buy into all the BS that a stock cast iron SBC intake doesn't make power, they are excellent just like the Pontiac intakes.
I'd also add that if you end up with a high rise manifold and need to use a drop base air cleaner for hood clearance, some of those will cost you twice the power you were hoping to make.......FWIW......
I'd also add that if you end up with a high rise manifold and need to use a drop base air cleaner for hood clearance, some of those will cost you twice the power you were hoping to make.......FWIW......