Power Steering Conversion

[Ralph E.]

Thinking about adding Power Steering to my 1967 327/300 no A/C car.
Which pulleys need to be changed. My water pump and harmonic balance have single pulleys. Any other advice would be helpful.

Ralph #37280

[Joe L.]

Re: Power Steering Conversion

Ralph------

Power steering is the only way to go. I HIGHLY recommend it for driving pleasure. When I ordered my 1969 new in 1969, I didn't want power steering and didn't order it. As time passed, I began to "appreciate the virtues" of power steering, so I added it to the car around 1986. Absolutely one of the 2 best changes I EVER made to the car (the other one was the addition of a soft top to the car I originally ordered with a hard-top only).

Anyway, as far as pullies go you have one of the "mystery" installations, pulley-wise. However, this is what I THINK you have and need. Your crankshaft pulley, if it's a single groove pulley should be a GM #3755820. This number should be stamped on it. To the front of this pulley you would add a 1 groove GM #3751232 pulley. This pulley will "sandwich" to the front of the existing pulley and be retained by the existing pulley-to-balancer bolts. This pulley is still available from GM.

I believe that the power steering pump pulley will be a stamped steel pulley of GM #3770509. However, I'm not 100% sure that this is the pulley you need. You MAY require the cast iron, "drop-down" style pulley of GM #3834720. In any event, you need one of these 2 pullies. I don't understand how the 3770509 can work, but GM says that's the one. Usually, the 3770509 works when the power steering drive pulley is the OUTERMOST groove of a THREE GROOVE crankshaft pulley system; the 3834720 works when the power steering drive pulley is the OUTERMOST groove of a 2 GROOVE crankshaft pulley system. The latter is what you have.

Hopefully, there are some others out there with a 1967 300 hp with N-40 and without C-60 that can "chime in" here and confirm which power steering pump pulley they have. Since one is a "pancake" style, stamped steel pulley, and the other is a "drop-down" style cast iron pulley, they are easy to identify at a glance.

Also, while the crankshaft power steeing drive pulley is still available from GM, the 2 power steering pump pullies are both discontinued. However, they are available in reproduction.

[Eugene B.]

Re: Power Steering Conversion

Ralph,
In addition to the pulleys, I believe that you will also need a PS pitman arm. Joe, please correct me if I'm wrong but I'm seem to remember that they are different.

Regards,
Gene

[Barbara S.]

Re: Power Steering Conversion

The pitman arms are definitely different. There are also different p/s pumps out there too. If you want to install a factory correct p/s pump, you should probably look at the JG and the assembly manual to see the correct configuration of the proper pump.
Tony

[Ralph E.]

Re: Power Steering Conversion

Checked the 1967 JG and I read it as the crank pulley should be a "stamped steel single grove pulley", I have a base engine. I assume this is in addition to the single grove pulley, GM#3755820, already on the crank. Can someone confirm. Most vendors include the new Pitman arm for PS with the kit! Not sure about about the reservoir, if it leans slightly forward. Still need to check that one with the vendors.

Ralph #37280

[Ralph E.]

Re: Power Steering Conversion

Additional observation. I noticed some vendors offer a PS add-on crank pulley in both deep groove and standard groove. Which is correct and which is better?

Ralph #37280

[John H.]

Re: Power Steering Conversion

Joe -

My power steering-only '67 327/300 has the single-groove crank pulley, and the "add-on" pulley spaces the belt groove forward to the third-groove position (the second-groove position is a "gap"), and the pump has the stamped 0509 pulley.

[Rob A.]

Re: Power Steering Conversion

I added p.s. to my '66 350HP and am very glad I did. I assume it might be different for the 300HP, but although the conversion kit came with the add-on crank pulley, I didn't require it for my application. I have seen quite a bit of discussion regarding whether it is needed or not, but it wasn't in my case. The kit should come with the new pitman arm, which is different. Tell them which HP you have, and they'll send you the correct type pulley for the p.s. pump, which in my case was the cast iron.

[Ralph E.]

Re: Power Steering Conversion

For my small block 300HP car should the add on pulley at the crank be #3751232? And is this a double groove pulley? Been looking at old posts regarding this and it gets a bit confusing. Remember, my small block 300HP only has single pulleys at the crank and water pump.

Ralph #37280

[Joe L.]

Re: Power Steering Conversion

Ralph-----

Yes, the add-on pulley you need is the SINGLE groove, GM #3751232. John's information confirms that the power steering pump pulley that you need is the stamped steel, GM #3770509, available in reproduction.

[Joe L.]

Re: Power Steering Conversion

John-----

OK, now I've got it. The only way that I could see that the '509' pump pulley could be used was if the drive pulley was the outermost groove of a 3 pulley system (or, if the "middle groove" was a "gap"). I did not think that the single groove power steering drive pulley sandwiched onto the single groove crank pulley would form a "gap". Now that I know it does, I understand how the '509' pump pulley will work.

[Joe L.]

Re: Power Steering Conversion

Ralph-----

You want to use the GM #3751232 pulley in conjuction with your existing 1 groove pulley. That's as specific as the advice can be.

[Ralph E.]

Re: Power Steering Conversion

Joe,
Once again you and John Hinckley are a wealth of knowledge. Your first post explained which pulley should be used and where very well. The confusion came from the vendors. Some insisting a deep groove pulley is required, another said cast iron, another said stamped. Once I got them to explain by using GM numbers it became evident who knew what they were talking about.
Thanks for your help.

Ralph

[Gerard F.]

Re: Power Steering Conversion

Ralph,

I have a 67/300HP w/no AC, and putting a power steering kit on was the best thing I've done for driveability. I got my kit from Corvette Central and it came with a replacement pitman arm.

Can't help you on the pulleys, as I added a Vintage Air system at the same time, and went with a 3 position crankpulley (polished aluminum) which I got from Vintage Air (along with a two position waterpump pulley). But the P/S on a 67/300 takes the third position from the engine on the crank pulley. The second position is for the A/C.

One thing to watch with the P/S kits is to use the forward lug (or closer steering ratio lug) on the wheel spindles. It's not apparent in the instructions, and if you use the manual steering lug you are in for a wild ride at high speeds. I know because I made that mistake.

But with P/S and A/C now, I'm a happy camper in CA.

Jerry Fuccillo
#42179

[Eugene B.]

Re: Power Steering Conversion

Ralph,
Sounds like you're well on your way to having power steering.

When you install the kit, check the directions to see if they tell you to move the tie rod ends from the back hole of the front spindle linkage to the front holes. My original PS, '65 has the tie rod ends in the front hole and the back holes are plugged. Perhaps the guys with more experience can comment on whether you will have to reset the toe-in after making this change.

You will definately enjoy the power steering around town, but be careful the first several times that you are at highway speed. In my opinion, the steering is overly sensitive and a small movement of the steering wheel make a big change in direction at 55 MPH.

Good luck with your project.

Regards,
Gene