I am planing on replacing the stock rack with the 15:1 rack and i was wandering what power steering pump i have to get to make it all go perfect install. I have a 86 cougar ls 5.0 :o
i don't think it matters,
i'm not 100% sure .... but a pump is a pump is a pump, and as long as it pushes fluid...it should be fine !!
Good luck
Every few months the question gets asked. A few say the original pump is fine. A few other say you MUST replace it with a Mustang pump. Then I post to say that I've had my original pump and brand-new Mustang rack working fine together since April 03, 2002.
Fairly certain they all used the same pump anyway, regardless of engine/steering rack/etc.
I'm using my original p/s pump from my old 88 5.0L bird(not 15:1 rack) on my 5.0L ho in my converted TC(15:1 rack) and it works just fine.
The Stang pump and T-Bird pump are the same part.
Sometime this weekend I will know,But when I bought the parts
All the parts were the same.
In 1985 (the only year for which I own a Helm manual), there were 6 different pumps available for Fox bodies. Out of these, 3 were available for our cars.
HBC-FM flowed 1.3 GPM with a min/max pressure relief of 850/1130 psi - 2.3L
HBC-FX flowed 1.4 GPM with a min/max pressure relief of 950/1230 psi - 3.8L w/handling, 5.0L
HBC-RN flowed 1.25 GPM with a min/max pressure relief of 950/1230 psi - 3.8L w/o handling
The 5.0L (auto) Mustangs used the HBC-FX
The 5.0L (manual) Mustangs used the HBC-FR. The 3.8L Mustangs w/o handling did too.
HBC-FR flowed 1.25 GPM with a min/max pressure relief of 850/1130 psi
For our purposes, flowrate is important because too little can cause rack hangups at parking-lot speeds when you try to move the steering wheel quickly and overwhelm the pump's flow capacity. On the other hand, too much flow can lead to cavitation and boiling fluid from long-term high-rpm usage. I doubt many of our cars have that problem though [unless you road race or drive in HPDEs].
Relief pressure is how much assist the pump is going to give the rack. If you have the two racks, but one has a higher relief pressure pump, the one with the higher pressure will be assisted more, and thus easier to turn.
The pumps from 5-oh Mustangs with automatic transmissions flow ~90% of std. T-bird pumps. Is this going to cause problems? I doubt it. The only time you might have an issue is during parking lot maneuvering.
Cars with the handling package (w/o handling) used the variable ratio rack. This rack had a 20:1 ratio on center, varying to 16:1 at the stops. It went 3.0 turns from lock-to-lock
Cars without the handling package (w/handling) used the constant 15:1 rack. It took 2.5 turns from lock-to-lock. Some racks (Mustang only I believe) are labeled 2.25 turns. These racks are physically the same as 2.5 turn racks, but they have a rack limiter on each side to stop rack/wheel/LCA interference.