Larger Power Steering Pulley - Impala Tech
Performance Our High Performance Area

 
LinkBack Thread Tools
post #1 of 5 (permalink) Old 04-12-2011, 12:08 AM Thread Starter
 
 
Join Date: Jul 2006
Location: Seattle, WA
Posts: 19
 
Larger Power Steering Pulley

I have an original 69 Caprice 427 pulley setup on my car at the moment. It appears as tho I am overdriving the P/S pump (to the point that the pump is now ruined). Does anyone know of a larger diameter pulley that still has the 2-groove setup for A/C? Or, is a single groove with the larger diameter an option? Wondering if the factory deep groove pulley might be an option.

I have upgraded the pump and steering box, but may have to resort to a larger pulley as well. (We'll see once I get it back together).

Thanks in advance,
Andy

1969 Caprice
427/335HP TKO-600
[email protected] mph
Slugbug is offline  
Sponsored Links
Advertisement
 
post #2 of 5 (permalink) Old 04-12-2011, 06:34 PM
Moderator
 
Join Date: Jan 2006
Posts: 12,383
 
What makes you think it is over driven? There is only one size pulley for all motors (6, SBC or BBC all share the same size diameter pulley with different pulley groove centerlines) as the pump does nothing with the wheels centered, and only moves an increasing volume of fluid as the wheel angle increases at the valve in the steering gear box.

If you run the fluid level low it will aerates the fluid and burn up the pump. If you have a SBC water pump pulley on your BBC, or a SBC pump pulley on your power steering pump then the belt mis-alignment will cause the seals to blow burning up the pump.

Mis-matched pulleys is a very, very common problem on a BBC engine as they were traded around like base base ball cards back in the late sixties (especially the unloved little 396 replacing 307 or 283 small blocks) and as such when they were installed in cars the pulleys never were replaced with a matching set of big block pulleys because the small block pulleys are close enough for most people (who didn't realize the head ache they were creating just because a SBC pulley will bolt up to the BBC mounting holes). The only SBC pulley that will not bolt up to a BBC is the crank pulley because of the bigger bolt and washer used with the big block (I have seen them drilled out to make them almost fit but wobbling wildly). However with the SBC pulley on a BBC the belts will not line up (which is very evident if there is another accessory like an A/C that sits close to it).

Big Dave
Big Dave is offline  
post #3 of 5 (permalink) Old 04-12-2011, 06:55 PM
Senior Member
 
Join Date: Jul 2008
Location: Michigan
Posts: 155
 
If you are running the correct factory pulleys and your P/S pump is going bad the pulleys are not doing it, you've got other problems. The terms "overdriving" or "underdriving" are used quite often in regards to water pumps - you want to overdrive the W/P to increase speed and help with cooling in higher horsepower and traffic situations and you would underdrive it in racing applications to free up some horsepower.
sz0k30 is offline  
 
post #4 of 5 (permalink) Old 05-14-2011, 01:20 AM Thread Starter
 
 
Join Date: Jul 2006
Location: Seattle, WA
Posts: 19
 
Just to close the loop...

All of my pulleys were the factory BBC pulleys. Since I rarely see any discussion about pulley diameters from various years for BBCs I thought I might have found something that would have helped my situation.

My previous P/S pump would blow fluid out the top of the cap during a hard run (6500). But, looks like the real issue was a 42 year old pump and lots of wear. A new pump from AGR Performance and some synthetic P/S fluid and all is well again. Saves me some embarrassment at the drag strip too (I used to keep an old sock over the P/S reservoir to keep the mist from dirtying the engine).

Sometimes I wish I had a manual steer car with no A/C...then I wouldn't be so inclined to have all this stuff actually work!

Thanks all,
Andy

1969 Caprice
427/335HP TKO-600
[email protected] mph
Slugbug is offline  
post #5 of 5 (permalink) Old 05-14-2011, 08:54 AM
Moderator
 
Join Date: Jan 2006
Posts: 12,383
 
Quote:
Originally Posted by Slugbug View Post
Just to close the loop...

All of my pulleys were the factory BBC pulleys. Since I rarely see any discussion about pulley diameters from various years for BBCs I thought I might have found something that would have helped my situation.

My previous P/S pump would blow fluid out the top of the cap during a hard run (6500). But, looks like the real issue was a 42 year old pump and lots of wear. A new pump from AGR Performance and some synthetic P/S fluid and all is well again. Saves me some embarrassment at the drag strip too (I used to keep an old sock over the P/S reservoir to keep the mist from dirtying the engine).

Sometimes I wish I had a manual steer car with no A/C...then I wouldn't be so inclined to have all this stuff actually work!

Thanks all,
Andy
A manual steering gear box (say off a Vega) also lightens the front end weight).

Big Dave
Big Dave is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Impala Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome