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Hello everyone. I purchased a numbers matching 1964 GTO post car. I took out the original 389, and purchased a 1965 421 from a gentleman who had just had it rebuilt. He had the engine in a 1965 lemans without power steering (he had single groove pulleys). My car is a power steering car. I thought that I would be able to just use the pulleys from my 389, but ran into a snafu. Rather than using a factory style harmonic balancer (that has the balancer inside the pulley), the previous owner of the 421 had a Powerbond/Dayco balancer installed (four bolt). I think this balancer is the style used by later Pontiac 400 and 455 motors. The factory crank pulley won't fit, so any pulley that I bolt onto it won't line up with my water pump pulley. I would like to retain the look of factory pulleys. I called Butler, and he said the easiest option would be to install a factory style balancer ($168). So, I have two questions,
1. Does anyone here have any experience matching factory style pulleys to the newer style Powerbond balancer? If so, any idea what part number waterpump and crank pulleys I would need for a car with power steering?

2. Is there any benefit in keeping the new style balancer (other than cost), or does the old style suggested by Butler as a quick fix perform the same.

Thank you in advance for any advice you can provide.
 

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If the later model, 1968 and up, balancer was used, has the timing cover/water pump been converted to the later style? If so, does the water pump use the 4" or 4 1/2" depth pump?

https://butlerperformance.com/n-13416-pontiac-timing-cover-identification.html

https://butlerperformance.com/n-13390-pontiac-water-pumps.html

Once you figure this out, do a "Google Custom Search" in the upper right hand corner of this page for pulleys. You should find a lot of material as well as part numbers for needed pulleys.
 

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First of all, thank you for your help on this. I do indeed have an eight bolt water pump that is bolted to a 1966-67 timing cover (the timing tab is -4, 0, +6). I also measured the water pump as the Butler link you attached described. I have included a picture of the measurement. It looks like it is 3.5 inches from the base of the water pump to the snout (not including the center alignment tab on the water pump. Any ideas on what I should do? Again, thank you for your input.
 

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You have the early 8-bolt water pump/timing cover set-up which is correct for your engine. You have a later type harmonic balancer. The early and later balancers are different sizes in outside diameter - you can check this by measuring off your 389 and compare it to your 421 balancer.

You timing marks will be off using the later style balancer on the earlier engine and you will be wondering why you can't get your engine timed correctly.

So, I would get the earlier type balancer as Butler suggests and then get the correct matching pulleys you will need to make your set-up work.

This is my suggestion, never seeing the engine nor knowing who built it or assembled it. :thumbsup:
 

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I ran into the same problem. To use the newer balancer on the earlier PS and alternator brackets I have found a fix, but this fix may not suit purists. Use a SBC two groove, aluminum, short water pump crank pulley. Re-size the pilot bore to Pontiac, drill the necessary 4 holes for mounting, and install a ⅛” shim between the pulley and balancer. All necessary items lines up. Cost $25 for the pulley vs. $200+ for old style damper and pulley. Note the Chevy pulley is 6.6” so you get an underdrive effect which may be good or not for your application. Paint the crank pulley black and carry on.
 

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I ran into the same problem. To use the newer balancer on the earlier PS and alternator brackets I have found a fix, but this fix may not suit purists. Use a SBC two groove, aluminum, short water pump crank pulley. Re-size the pilot bore to Pontiac, drill the necessary 4 holes for mounting, and install a ⅛” shim between the pulley and balancer. All necessary items lines up. Cost $25 for the pulley vs. $200+ for old style damper and pulley. Note the Chevy pulley is 6.6” so you get an underdrive effect which may be good or not for your application. Paint the crank pulley black and carry on.

I like "fixes" myself if they are cost effective and work - and it doesn't have to be factory correct. So here is where I would need a little more info.

The 2-groove SBC aluminum pulley is from what year application & engine? Is this later model as most early stuff is steel.

Is the SBC pulley the same outside diameter as the Pontiac so you don't get an overdrive/underdrive situation?

I understand opening up the center hole of the SBC pulley to fit the larger water pump shaft that holds it in place. How did you go about drilling the 4 repositioned fan bolt holes - drill press or free hand it? Or just wallow out the existing pulley holes? How far off is a SBC as compared to the Pontiac pulley?

No problem on the 1/8" shim on the lower pulley/balancer. I might get real cheap and us flat washers to move it out 1/8"?

How did you correct the difference in the size of the earlier 2-piece 5.25" diameter balancer hub versus the later one piece 6.75" diameter balancer hub? Timing marks will be off when trying yo use the balancer hub mark with the timing cover's scale readings - assuming that the 4-bolt hole Powerbond/Dayco balancer is a replacement for the later 1969 and up engines.

Timing tape?
 

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PontiacJim: the SBC pulley is for the crank, not the water pump. It is readily available from many suppliers on Ebay. Just be sure it is for a Chevy short water pump application. As previously stated it is 6.6” and will be about a 15% underdrive. Accurate timing by timing tape after finding true TDC. 4 mounting holes located using a transfer punch using an old Pontiac pulley. The pilot diameter is the important dimension to eliminate run out.
 

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I ran into the same problem. To use the newer balancer on the earlier PS and alternator brackets I have found a fix, but this fix may not suit purists. Use a SBC two groove, aluminum, short water pump crank pulley. Re-size the pilot bore to Pontiac, drill the necessary 4 holes for mounting, and install a ⅛” shim between the pulley and balancer. All necessary items lines up. Cost $25 for the pulley vs. $200+ for old style damper and pulley. Note the Chevy pulley is 6.6” so you get an underdrive effect which may be good or not for your application. Paint the crank pulley black and carry on.

I like "fixes" myself if they are cost effective and work - and it doesn't have to be factory correct. So here is where I would need a little more info.

The 2-groove SBC aluminum pulley is from what year application & engine? Is this later model as most early stuff is steel.

Is the SBC pulley the same outside diameter as the Pontiac so you don't get an overdrive/underdrive situation?

I understand opening up the center hole of the SBC pulley to fit the larger water pump shaft that holds it in place. How did you go about drilling the 4 repositioned fan bolt holes - drill press or free hand it? Or just wallow out the existing pulley holes? How far off is a SBC as compared to the Pontiac pulley?

No problem on the 1/8" shim on the lower pulley/balancer. I might get real cheap and us flat washers to move it out 1/8"?

How did you correct the difference in the size of the earlier 2-piece 5.25" diameter balancer hub versus the later one piece 6.75" diameter balancer hub? Timing marks will be off when trying yo use the balancer hub mark with the timing cover's scale readings - assuming that the 4-bolt hole Powerbond/Dayco balancer is a replacement for the later 1969 and up engines.

Timing tape?
I don't understand you getting involved ? This fix is for Doug e Doug not you correct? I'm sorry but just don't understand why you have to get involved in everybody thread . Maybe it's just me . Happy holidays to all. Doug
 

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The pulley info is interesting but all the people are confusing. There is dd68gto, Doug E Doug, and Dprstn. Is this indicative of three people with pulley problems or one person with different screen names posing the problem to the forum. Can anyone clarify this?

Thanks.
 

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I don't understand you getting involved ? This fix is for Doug e Doug not you correct? I'm sorry but just don't understand why you have to get involved in everybody thread . Maybe it's just me . Happy holidays to all. Doug
Doug it is just you. :banghead::STFU:
 

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The pulley info is interesting but all the people are confusing. There is dd68gto, Doug E Doug, and Dprstn. Is this indicative of three people with pulley problems or one person with different screen names posing the problem to the forum. Can anyone clarify this?

Thanks.
"Doug E Doug" & "Dprstn" appear to be same, look at join date and post numbers. A while back this site had an issue that screwed up our screen names and passwords. I had to have my password changed and was able to keep my screen name- so assume maybe why the 2 names?

PontiacJim is me.

David Shuff is another poster trying to supply a fix.

1968gto421 is you asking the question I am answering to clarify.

dd(dumb douche bag)68gto is the instigator on this forum whose job is to act stupid and inject his sarcasm towards my posts whenever possible.

Hope that straightens things out. :thumbsup:
 

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64 GTO waterpump and crank pulley setup

Hi Guys,
Thank you all for your input. I apologize for any confusion. I did create the first post, but couldn't log in for some reason to repost. While I am not a purest, I would like to retain the factory look of the engine. Since it has the timing cover from a 1966-67, it isn't necessarily period correct anyway. I am considering doing the 11 bolt water pump/timing cover swap now though. If I went ahead and purchased the OEM style balancer from Butler, so I could keep the pulleys from my 389, would I run into this same issue later when I convert it to an 11 bolt water pump and later timing cover? Thanks again.
 

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Hi Guys,
Thank you all for your input. I apologize for any confusion. I did create the first post, but couldn't log in for some reason to repost. While I am not a purest, I would like to retain the factory look of the engine. Since it has the timing cover from a 1966-67, it isn't necessarily period correct anyway. I am considering doing the 11 bolt water pump/timing cover swap now though. If I went ahead and purchased the OEM style balancer from Butler, so I could keep the pulleys from my 389, would I run into this same issue later when I convert it to an 11 bolt water pump and later timing cover? Thanks again.
Reach out to BLK69JUDGE ( send him a pm) on this site. He will cross reference what you have and what pulley you need. I hade a similar problem few years back and got all the correct parts from forum members here and on PY . As far as Pontiac Jim comment he is obviously off his meds . But when you have over 4000 posts like him he must know what he is talking about. Jim the name calling is getting old. Doug
 
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