Problems with Serpentine Setup on my 79
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Problems with Serpentine Setup on my 79
Ive got a ZZ383 im dropping in a 79, and Im having a clearance problem with the balancer touching the center crossmember, and the idler pulley is hitting the crossbar mount for the upper control arm on the right side. It is a setup from GM performance parts. Anyone have any insight? 
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
Can you post a few pics?
The ZZ383 should be no different in the mounting and positioning than a standard small block right?
The crank pulley may not be correct, like a BBC crank pulley that maybe has a larger diameter and a longer back spacing.
I put serp on my small block, and I have a full finger between the pulley and the front cross member.
I do not have a cross bar, but I think you may have to go at it with a grinder to give you a little room. Can it be pulled apart and re-welded for more room?
The ZZ383 should be no different in the mounting and positioning than a standard small block right?
The crank pulley may not be correct, like a BBC crank pulley that maybe has a larger diameter and a longer back spacing.
I put serp on my small block, and I have a full finger between the pulley and the front cross member.
I do not have a cross bar, but I think you may have to go at it with a grinder to give you a little room. Can it be pulled apart and re-welded for more room?
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Well I dropped the motor in for a test fit, and luckilly I did because thats when I noticed these issues. I have A/C so Im thinking that might be why the balancer pulley is larger. Id take some pics, but I took the motor back out to address the issues. Some pictures I am seeing shows the idler pulley mounted further to the inside. It seems as though I might be seeing setups used from 4.3L motors.
Team Owner
Joined: Aug 2006
Posts: 24,125
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From: Columbia Missouri
Well I dropped the motor in for a test fit, and luckilly I did because thats when I noticed these issues. I have A/C so Im thinking that might be why the balancer pulley is larger. Id take some pics, but I took the motor back out to address the issues. Some pictures I am seeing shows the idler pulley mounted further to the inside. It seems as though I might be seeing setups used from 4.3L motors.
All the small blocks have similar setups. The driver bracket is the same all across the board. Same goes for the water pump pulley. The power steering pulley has two sizes, and the crank pulleys are all the same for the small block with the exception of the ones that are integrated into the balancer itself.
The passenger bracket has two variations. One, the 4.3 and truck bracket, does place the tensioner a little closer to the center of the setup. The F-body passenger bracket leaves more space between the two. The height is almost the same for both of them.
Some had an idler pulley mounted down where the smog pump would go, but the casting is the same so it can be removed, and a smog pump or delete pulley can be mounted.
I suspect that you may have a BBC serpentine pulley on the crank. I have not been able to find two to compare, but I think they are different diameters and this may be causing your cross member clearance problem.
Can you measure the crank pulley's overall diameter for me?
Team Owner
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From: Columbia Missouri
Thread Starter
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Yeah I have it all together on the motor. I see that some people leave the idler pulley off the motor, but Im not sure if that will be ok or not since the run from the compressor to the crank is pretty long.
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
That actually is not a problem. Here is a pic of mine, which is the F-body setup, modified to house a second alt and no lower pulley at all.
Lets go over the common things. Your 383 is a small block casting so it should be the same. The motor mounts are probably good and the same as mine. With the motor and mounts in the same place you should have at least a full finger between the pulley and the cross member.
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Team Owner
Joined: Aug 2006
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From: Columbia Missouri
The Camaro guys at the Thirdgen.org place have been deleting that lower pulley for years now and no one has complained of a slapping belt or insufficient contact with the A/C pulley.
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
That's what I was just thinking. If the transmission tail is just a little too high it will drop the front of the motor down.
Team Owner
Joined: Aug 2006
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From: Columbia Missouri
You are very right, they did actually they had a good reason and it was a place to mount the smog pump on a lot of cars. For the cars that did not receive the smog pump, they filled the space with an idler.
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