AL vs Cast intake
Thread Starter
Pro
Joined: Dec 2009
Posts: 637
Likes: 110
From: Flakewood Wrench, FL
You will HAVE to pull the distributor to swap intakes....there are two reference points to mark and then its a breeze. Mark the distributor position (normally you would mark it at the intake but the intake will be swapped); a piece of that blue tape on a valve cover in line with the vac advance hose tube fitting aligned via straightedge will do it. Then, in a similar fashion, mark where the rotor is pointing. Do NOT bump the engine over during the swap. All you have to do then is reinsert the distributor according to your marks. JohnZ has written an excellent article on the procedure....if you don't have it, or others, will post it...
Melting Slicks
Joined: May 2007
Posts: 3,461
Likes: 18
From: cooper city florida
When you install the aluminum intake, you might want to consider blocking off the exhaust crossover on the intake with F.I. intake gasket's. If you do, you will need to stop by any muffler shop, and have them install an H pipe somewhere behind the tranny. Good mod with today's gas, and you will pick up a little extra lower end torque with the H pipe.
Race Director
Joined: Aug 2004
Posts: 15,316
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From: NorCal
You will HAVE to pull the distributor to swap intakes....there are two reference points to mark and then its a breeze. Mark the distributor position (normally you would mark it at the intake but the intake will be swapped); a piece of that blue tape on a valve cover in line with the vac advance hose tube fitting aligned via straightedge will do it. Then, in a similar fashion, mark where the rotor is pointing. Do NOT bump the engine over during the swap. All you have to do then is reinsert the distributor according to your marks. JohnZ has written an excellent article on the procedure....if you don't have it, or others, will post it...
Remember that when you pull the dizzy the rotor will "rotate" slightly from that mark due to the spiral cut gears. When you reinstall it you need to start from the same offset it had from your mark so that it will wind up in the correct position as it again rotates on its way back down/in. If you try to start the re installation process with the rotor lined up with the mark you will wind up a tooth off on the final position.
Thread Starter
Pro
Joined: Dec 2009
Posts: 637
Likes: 110
From: Flakewood Wrench, FL
When you install the aluminum intake, you might want to consider blocking off the exhaust crossover on the intake with F.I. intake gasket's. If you do, you will need to stop by any muffler shop, and have them install an H pipe somewhere behind the tranny. Good mod with today's gas, and you will pick up a little extra lower end torque with the H pipe.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
When you put your distributor shield back on, make sure the 12V feed to the coil isn't binding/abraiding against the shield or you could burn you car to the ground.
Last edited by MikeM; Jun 27, 2015 at 12:02 PM.
Thread Starter
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Joined: Dec 2009
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From: Flakewood Wrench, FL
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Thread Starter
Pro
Joined: Dec 2009
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From: Flakewood Wrench, FL
Good advice. One step further is to first pull the distributor cap and then crank the engine until the rotor and the advance tube hose fitting line up. Only one position/mark to keep track of that way!
Remember that when you pull the dizzy the rotor will "rotate" slightly from that mark due to the spiral cut gears. When you reinstall it you need to start from the same offset it had from your mark so that it will wind up in the correct position as it again rotates on its way back down/in. If you try to start the re installation process with the rotor lined up with the mark you will wind up a tooth off on the final position.
Remember that when you pull the dizzy the rotor will "rotate" slightly from that mark due to the spiral cut gears. When you reinstall it you need to start from the same offset it had from your mark so that it will wind up in the correct position as it again rotates on its way back down/in. If you try to start the re installation process with the rotor lined up with the mark you will wind up a tooth off on the final position.
Race Director
Joined: Apr 2015
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From: Fresno California
What tuxnharley said. Note where the rotor is pointing, and note where it rotates to when you pull the dist. It usually will rotate about 20-30 degrees. When you go to install, have the rotor at the same position it shifted to when you pulled it. When the dizzy is seated, the rotor will turn and be exactly where it was before the r&r. Works every time.
Melting Slicks
Joined: Apr 2006
Posts: 2,331
Likes: 61
From: Sunnyvale CA
Just an idea....
Also wouldn't have to think about the water pump bypass. Just throwing the suggestion out there for consideration.
Is it safe to assume you're already sporting the finned aluminum valve covers?
Steve
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Joined: Dec 2009
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From: Flakewood Wrench, FL
Have you considered cleaning your 300 HP manifold and then painting it with a high-temperature aluminum paint? Then you wouldn't need to change choke rod (assuming you're using a divorced-choke Holley), thermostat housing, pump-to-carb fuel line, upper radiator hose, vac advance tube..... (Did I leave anything out?)
Also wouldn't have to think about the water pump bypass. Just throwing the suggestion out there for consideration.
Is it safe to assume you're already sporting the finned aluminum valve covers?
Steve
Also wouldn't have to think about the water pump bypass. Just throwing the suggestion out there for consideration.
Is it safe to assume you're already sporting the finned aluminum valve covers?
Steve
Thread Starter
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Joined: Dec 2009
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From: Flakewood Wrench, FL
What tuxnharley said. Note where the rotor is pointing, and note where it rotates to when you pull the dist. It usually will rotate about 20-30 degrees. When you go to install, have the rotor at the same position it shifted to when you pulled it. When the dizzy is seated, the rotor will turn and be exactly where it was before the r&r. Works every time.
That seems easy enough. I'm assuming the dizzy body has to be replaced in exactly the same position as it was prior to removal.
Team Owner
Joined: Aug 2007
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Army
Look at the bottom of a distributor - the gear is helical... On a GM IIRC there are 13 teeth. So 360*/13 teeth is 27.6* or thereabouts. As mentioned, that's the displacement factor when you pull/replace the distributor. The Lars method doesn't require this "Kentucky windage". You seat the distributor in its approx correct location with the main point being getting the oil pump drive to engage (the distributor should sit ALL the way down). Then, by lifting the distributor ever so slightly you can 'walk' the rotor gear-by-gear to the correct position in steps and then do the final alignment of the body. This disengages the helical gear just barely but keeps the oil pump drive in place
Quite easy. No looking down the dizzy hole with a flashlight and screwdriver trying to align the pump gear. Or completely repulling the dizzy multiple times to get the right guesstimate for the correct rotor position.
I just did this the two days ago when I put points in my '63 (yes I said points)....
Quite easy. No looking down the dizzy hole with a flashlight and screwdriver trying to align the pump gear. Or completely repulling the dizzy multiple times to get the right guesstimate for the correct rotor position.
I just did this the two days ago when I put points in my '63 (yes I said points)....
Last edited by Frankie the Fink; Jun 28, 2015 at 07:13 AM.
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
So let me get this right... the rotor will reverse itself back to where it was before it got pulled providing it's indexed where it was after it got pulled?
That seems easy enough. I'm assuming the dizzy body has to be replaced in exactly the same position as it was prior to removal.
That seems easy enough. I'm assuming the dizzy body has to be replaced in exactly the same position as it was prior to removal.
In my considerable experience over the years, maybe one out of dozen times when you put the distributor back in will the distributor line up with the distributor shaft and the distributor won't go all the way down against the manifold.
No problem, just bump the starter a couple of clicks and the distributor/oil pump shaft will align and the distributor will drop on down and seat.
If you're in the right notch, typically the vacuum advance nipple will be pointing at the RR inside valve cover bolt with the rotor pointing to #1 cap terminal.
I never look down in the hole to see where the gear is, don't fiddle faddle with a long screwdriver, just drop it and bump the starter and good to go.
Different people have their own personal way they like to do this. There's more than one way and some of them are even wrong but the engine will still run okay.
Last edited by MikeM; Jun 28, 2015 at 07:11 AM.
Team Owner
Joined: Aug 2007
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Army
Bumping the starter works...I did that a lot, but the downside being you better have the dizzy/rotor alignment spot on...cuz once you rotate the engine; its a whole new ballgame.
Then you get to do the "where the hell is TDC drill"...
Then you get to do the "where the hell is TDC drill"...
Thread Starter
Pro
Joined: Dec 2009
Posts: 637
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From: Flakewood Wrench, FL
Look at the bottom of a distributor - the gear is helical... On a GM IIRC there are 13 teeth. So 360*/13 teeth is 27.6* or thereabouts. As mentioned, that's the displacement factor when you pull/replace the distributor. The Lars method doesn't require this "Kentucky windage". You seat the distributor in its approx correct location with the main point being getting the oil pump drive to engage (the distributor should sit ALL the way down). Then, by lifting the distributor ever so slightly you can 'walk' the rotor gear-by-gear to the correct position in steps and then do the final alignment of the body. This disengages the helical gear just barely but keeps the oil pump drive in place
Quite easy. No looking down the dizzy hole with a flashlight and screwdriver trying to align the pump gear. Or completely repulling the dizzy multiple times to get the right guesstimate for the correct rotor position.
I just did this the two days ago when I put points in my '63 (yes I said points)....
Quite easy. No looking down the dizzy hole with a flashlight and screwdriver trying to align the pump gear. Or completely repulling the dizzy multiple times to get the right guesstimate for the correct rotor position.
I just did this the two days ago when I put points in my '63 (yes I said points)....
If I'm really careful, do I need to leave the distributor off during installation of the engine/trans? Or is it simply asking for trouble not to?