Thread: Mustang II Rack & Pinion

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I have read a lot about using Thunderbird racks because they are more suited for the GM power steering pumps. Can anyone tell me what specific years are best for use with the GM Type II pump?
I am building a 1938 Chevy PU and the current rack is 40 years old. I either need to change it to the Thunderbird rack or change the flow control. If I change the flow control I still have a 40 year old rack to deal with. I am nearing the poiint that I need to take care of this. Any help would be most appreciated.

I'd recommend that you make/adapt brackets as necessary, and get the pump that matches the rack regardless what engine you're running. If you're wanting a T-bird rack get the associated T-bird pump and eliminate any problems.

Roger, I can appreciate your thought on this but I spent many hours making the brackets that I have on this to make it look 'Factory'. I installed a Corvette LT1 in this 38 Chevy pickup without modifying the sheet metal in any way. I had to cut down the existing Corvette brackets and mounts to compact everything to clear, something that don't want to go through again. The majority of lookers will never be able to tell that it was modified.
I did this for a friend of mine that wanted the factory 'look'. I even offed to purchase a Street & Performance set-up for him because of the difficulty of the fit and he didn't want it. I found the Billet Specialties flow control I am considering but will still have a 40 year old rack. I have heard of excellent results of using the Thunderbird rack with the GM pump without having to change the flow control. I can get a rebuilt rack for under $70 but want to know for sure what model most have had success with.
My friend had the truck that he had started on 15 years before I met him. I looked it over and we disassembled the complete drive train. I lowered the engine 3 inches, took out the 307 and turbo 400 and it now has the Corvette LT1 383 Stroker with a 4L60E sitting in place. We just recently rebuilt the transmission, removed the original rear end and suspension and installed a later model GM leaf spring with 373 posi. I am extremely proud of everything on the truck. It is a very clean install.
I am getting ready for the first start-up after I get all the exhaust parts in and get it fabricated up. I am hoping to eliminate any problems associated with twitchy steering before I start installing the cab on the truck and paint it.
It has been a while since I have been on the CHR forum. Just about every time I try I get a message that I don't have permissions. I was very much surprised that I was able to get on after the third try today. So far, So good.

Ed,
I appreciate where you are, and I cannot offer you any specific advice on selection. There has been considerable discussion on this subject, using GM pumps on Ford racks, and a lot of misunderstandings about the interface. You are mentioning flow control which is a big plus, because it seems that many guys think that it is a pure pressure issue, while it is a combined pressure and flow issue. I suggested to the last guy looking that he contact Borgeson, since they're one of the biggest players in the power steering arena, and they sell kits to reduce pressure and flow.

Borgeson Part no. 899001, comes with the instructions shims every thing you need to reduce the pressure down from 1000 psi to 800 psi that the mustang rack needs. used many times very simple. Jonathan

Ed,
I appreciate where you are, and I cannot offer you any specific advice on selection. There has been considerable discussion on this subject, using GM pumps on Ford racks, and a lot of misunderstandings about the interface. You are mentioning flow control which is a big plus, because it seems that many guys think that it is a pure pressure issue, while it is a combined pressure and flow issue. I suggested to the last guy looking that he contact Borgeson, since they're one of the biggest players in the power steering arena, and they sell kits to reduce pressure and flow.

I'm just wondering since you have it all apart why not use GM rack and pinion???

Hi Charlie, mostly because it is a M II front end that was added to the chassis before I got involved. The owner did a decent job installing it. I really hate to pull the rack, it would be much simpler to install the flow control. I have read a lot about the T-Bird rack being more compatible with the pressure of the GM Type II with good results. I know this has been hashed out many, many times but there does not seem to be a definitive answer, everyone has an opinion and we all know what one person perceives as fine is not necessarily the best. I have read many threads about the flow control and pressure on the rack when I know that what the person is describing is castor and other alignment issues. I have never heard of installing a GM rack on a Mustang II front end, is there something that works well?
Roger, I am glad you mentioned the flow issue because there is a difference between the flow and pressure. Billet Specialties advertises that their flow control will cut the flow to 2 GPM, which is more desirable for the M II rack. They claim it works well and stops the twitching. I have never seen this rack in operation but I know it is 40 years old and would be a lot easier to replace before the cab is installed. Advance Auto has a Cardone Reman rack # 22-215 for $67. With a 30% coupon it will be hard to pass it up. I just don't know if this is the correct rack to replace the M II rack. I was hoping that someone on the forum would know.

Originally Posted by Hurst01

It has been a while since I have been on the CHR forum. Just about every time I try I get a message that I don't have permissions. I was very much surprised that I was able to get on after the third try today. So far, So good.

I'm on here everyday and I still get that message, too! When you see it, go ahead and click on "Todays Posts" and it will probably take you on into the forum.

As for the rack, if you're concerned about the Mustang II rack being 40yrs old, why not just get a new one, because you know it fits, then add whatever device you need to control the pressure? Of course, someone may come along and tell you exactly what Tbird rack will accomplish your purpose.....

Just remember that the basic thing about the M2 rack is that it fits that front end geometry for bump steer---to use some other model rack you probably have to mod the length to match the inner pivot points of the lower a a rms

OK, I think I have this figured out. I ran across a link on ebay from a well known Speed and Performance company advertising a Thunderbird rack:

POWER: Rebuilt power rack from 1982-88 T-bird. Also fits aftermarket Mustang II crossmembers. Bushings included. (Can be used with a Saginaw GM power steering pump without any additional valves or inline pressure regulators). Overall width is 45-1/8" with 15-1/2" mount centers. Must use offset bushings (910-34342) to mount to original Mustang II crossmembers. 3/4"-36 spline input shaft.

It requires the use of offset bushing to match the MII cross member which makes it a direct fit. I was searching on Advance Auto Parts site and found the same rack rebuilt by a different supplier for $53. I also found a 30% off coupon for Advance which brought the price down to about $38 plus core charge. I purchased the offset bushings on ebay for $39. Have to make sure it is NOT for the performance suspension. This one turns 3 turns from lock-to-lock, whereas the performance suspension rack turns 2.5 turns lock-to-lock which will still have a tendency to be very touchy.
I am going to take some pictures of the build this weekend and post them on here if anyone would like to see them. We are going to get the stainless exhaust installed and engine started before the cab is installed. Still have a lot of work to do on the cab. Once the engine is started it will be my turn to get some work done on my 29 Buick and the cab will come later. My poor old car has been sitting for 7 years while I have been working on other peoples cars. I would say it is time for a little payback.

Originally Posted by Hurst01

I am going to take some pictures of the build this weekend and post them on here if anyone would like to see them.

Are you kidding?? OF COURSE We want to see pics!!!! Pics are a requirement!!!!

You might want to make sure the pricing is correct since you don't have correct core for a rebuild deal

I already bought and paid for it. There is a $55 core charge that I am supposed to get back when I return the other rack, but even if I don't, it is only $93 so I won't complain. Still a decent deal.

I have a M2 on my car now with GM pump, I used the borgenson shim kit ( very easy) and shimmed my pump to match my rack, as for the years of T bird rack ( which I also got from NAPA for about $130) was the measurement of the 2 mounting holes, If I remember right, one rack has 14in. between the 2 mounting holes and the other has 15in. regardless of year the mounting holes is the deciding factor.
I also bought the adapting supply/return lines from borgenson.

Godspeed
MrC.