multi belt issue

[JurgenS]

I'm building a SBC toppped with a Pro Flo XT manifold.

The old steel accessories bracket had to go because of the throttle body inlet track and waterneck hitting the back of it. I replace it with later aluminum brackets.

OLD

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NEW (well half of them at least)

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The issue I'm facing now is that the pulleys don't line up anymore. The waterpump and cranckshaft pulley are about 3/16 more inwards. Not sure from which engine the alu brackets come from but I thought they were all the same for a sbc but apparently I was wrong. The alternator, AC and PS are still the same so the only difference are the brackets.

Anyone got an idea if there are different pulleys or anything else that is different? I cannot change the crankshaft pulley very easy because I already have a trigger wheel welded on it for the EFI. Another solution would be to make a spacer for it.

 

[99'Subourbon]

I'm building a SBC toppped with a Pro Flo XT manifold.

The old steel accessories bracket had to go because of the throttle body inlet track and waterneck hitting the back of it. I replace it with later aluminum brackets.

OLD

You must be registered for see images attach

NEW (well half of them at least)

You must be registered for see images attach

The issue I'm facing now is that the pulleys don't line up anymore. The waterpump and cranckshaft pulley are about 3/16 more inwards. Not sure from which engine the alu brackets come from but I thought they were all the same for a sbc but apparently I was wrong. The alternator, AC and PS are still the same so the only difference are the brackets.

Anyone got an idea if there are different pulleys or anything else that is different? I cannot change the crankshaft pulley very easy because I already have a trigger wheel welded on it for the EFI. Another solution would be to make a spacer for it.

Spacer it is - It just seems like QC of these later manufacture pieces just isn't that great. Anything I have ever put on any of my vehicles for the accessories has required spacers, direct replacement or not.

 

[98_k1500]

That, or depending on clearance, shave the back of the bracket some.

 

[JurgenS]

I guess a spacer is easier and I don't have a mill do shave the brackets. I understand that a little difference is ok for QC but 3/16??

 

[JurgenS]

I got the spacers and everything lines up perfectly now but I ran into another problem with the belt tensioner.

The belt is rubbing the underside of the tensioner although in the picture I used a belt that's too short. Also the tensioner came of the old steel bracket, not sure if they are the same as those for the newer brackets. Anyone knows? In this picture there's no load on the tensioner.

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Second picture is with no tension applied.

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Here I move the tensioner around with the belt loose and it hits the water pump pulley. This might not be an issue but will depend on the length of the belt.

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The tensioner must be in a lower position then shown in the picture below otherwise it won't clear the inlet to the throttle body.

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This is how I run the belt (like setup in the middle but without the idler pulley):

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A lot of question for a rather simple question, am I using the correct tensioner? I have no idea from which exact car these brackets come from but they are for a SBC 350 (which I also have).