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Discussion Starter #1
hi everyone, i am a new member from aurora colorado. i have a street/strip '65 GTO i drive around and to Bandimere speedway to compete. i want to lose the power steering and go manual. through summit (and others) you can buy a borgeson box that is patterned after the venerable saginaw 525. they come with pitman arm and rag joint and are supposedly a bolt in. the cost is between $400-500 dollars. ouch.

my question is this-- vega boxes are available for later year g- bodies. they require some adapting but i don't know what. manual steering boxes from 80s vintage S-10s replace 70s era a-body power steering boxes. my car is somewhat lightened, so a smaller box for a lighter car will not be overwhelmed as easily. does anybody have any knowledge about this? is there something out there that would work on my early a-body? i would love to find a manual box that would be safe but as light as possible and also install with a minimum of adapting.
thanks,
john
 

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welcome to the forum!

Originally, the early GM A body's used a Saginaw 525 box and the early manual strg A body pitman arm that has a small tapered hole where it attaches to the centerlink. Somewhere in '67, the pitman arm changed casting numbers and the hole became larger. I can get the casting numbers if needed. This is from memory, as have pulled a bunch of Saginaw manual stg boxes and am converting both of my '71 HO 233's to factory manual strg. like yourself, for weight saving.

Since you already have the PS box and PS pitman arm for your '65, it would be a lot cheaper to buy the '80's S10 manual strg box and use you current '65's PS pitman arm, as the splined end on the original PS pitman arm will work perfectly with the S10 box. The Vega box is a totally different box, not sure I'd go that route unless car was extremely lightweight drag car, and a rack setup was not in the cards.

Hope this helps.
 

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Discussion Starter #3
hey pinion head,
(that doesn't sound very nice)
thank you for the prompt info packed reply....so i am correct in assuming the 80s era manual steering box from the s-1 will bolt up to my car? i understand i use my pitman arm. what about the rag joint? what do i do there? and finally, the s-10 box is lighter than the saginaw?
thanks again, john
 

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On the S10 boxes, if you want the absolute lightest, watch for an early style (3 bolt cover). they are around 4 1/2 lbs lighter than the late style (4 bolt cover). The early style accepts an original early GM pitman arm. The latter style S10 manual box has a larger splined shaft and accepts the PS pitman arm. Have always had an easy time moving the latter style S10 boxes, as most guys converting to manual strg, have PS on their car. For many years, finding several of the rarer original manual strg pitman arms (not A body's), well you paid through the nose, just for the pitman arm. try and source a '69 V8 Bird pitman arm, for example.

On the rag joint for the latter S10 box, I believe it's a Dorman 31011, it's been quite a while since I bought one. On the original manual boxes used in '64-74 GM's, the rag joint is a Lares 200. I've bought many more of those, for quite a was buying at whls from Chevy vendor friend.

Weight savings wise, my '71's factory style manual strg bracket and single groove pulleys are right at 30 lbs lighter than the previous '71 style PS set-up. have not even weighed and compared my cars original thick rim Formula wheels to the standard plastic steering wheel, but believe the std wheel is lighter, as well. If one had a '64 Pontiac Abody with the '64 particular pump and cast iron bracket, the weight savings would be even more! At least Pontiac got rid of that heavy PS pump set-up for '65 models.

If I was to go to a 3 bolt style S10 box and reuse my PS pitman arm, am betting would save another 2-3 lbs. Having had the early S10 boxes before, am a little leery of using one in a 3500 lb A body. Saginaw upgraded to the S10 manual box to what amts to a more HD version for a reason. Am not an engineer, but understand if a part is not holding up, it gets upgraded, in order to reduce warranty claims.

Feel free and weigh your parts when doing the swap and post back. Best to you with your '65.
 

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Discussion Starter #6
thank you so much for your detailed response and your kind words....you really know your stuff...it sounds to me like the later model 4 bolt cover s-10 box is what i need, especially if it accepts my power steering pitman arm with no problems. do you happen to know what the weight difference is between the 4 bolt s-10 box and a saginaw 525 that would fit my early a-body? thanks again for your help. do you drag race your '71s?
 
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