#1
I wondered if power steering could be added to the
Fiero, so i headed to
Pennock's "Merkur power steering rack"
and found out that yes, of course, people have done this. (Also there
was 2 different ratios for the steering racks, and one is referred to as the
"Quick Turn Factory Rack".) There are currently two power steering racks which
are considered for the Fiero, the Merkur and the Chevette, but both require
modification and at this point I dont know which one requires less work.
Shown here is the
Zimmer Quicksilver
which used the Merkur rack.
(4/16/03)
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#2
"Pwr Steering questions"
Here is a Chevette rack on a lambo chassis from
Craig Nadeau. No one is sure this rack fits in a stock
Fiero.
Modifications include either moving the Fiero mounts or using
Chevette mounts.
The rumor is that the Fiero tie rod ends will screw
right onto this rack, but a 3" extension is
needed on one side.
Also an aftermarket U-joint is needed to connect the rack to the Fiero steering
shaft.
Cost of the 1981-87 Chevette (gas or diesel) power rack
is $230 at Autozone
(ATSCO PN 6405)
or partsamerica (PN 22-102).
(4/16/03)
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#3
The Merkur/XRTI (or Xr4ti) 1985-1989
(2.5 quick turn ratio - or is it 12.5:1?) is shown here in a Fiero.
Modification of the Merkur includes:
removal of some housing on one side
shortening and squaring of the pinion shaft
Modification to the Fiero includes:
intermediate steering shaft must be shortened
(cut in two places and welded back together)
rubber intermediate shaft cover
rubber rack mounts
Again, the cost is said to be about $230 at
Autozone but bwayne on
Pennock's
suggested somebody could produce modified racks for $700.
Fiero tie rod ends and adjustment sleeves are used.
(4/16/03)
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#4
Bwayne wrote up the mods to the Merkur in
"Quicksilver Power Steering - page 2" included here
for safe keeping, tho there are more pics on the Forum.
"This first picture is both the stock Fiero and a stock Merkur rack.
Note that the right side (which is on the left in this picture) has a flange that is part of the casing. This must be machined off."
(4/16/03)
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#5
"Following are two closeups, one of the Fiero pinion shaft."
(4/16/03)
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#6
"and the second of the Merkur pinion shaft. Note the length of the shaft and the shape, although it is difficult to see in the picture."
(4/16/03)
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#7
"The first thing is that the shaft itself must be shortened to exactly 2". Although I have never seen the Merkur rack in its original form, inspection of the modified unit shows that this shaft is not a single piece. There seems to be a shaft over a shorter stub with a shear pin or something holding them together. These need to be lined up properly, so my guess is that the shortening must be done with the pieces put together--not separated, cut and reconnected. Someone with an original rack may be able to shed more light on this detail."
(4/16/03)
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#8
"In shortening the shaft I think that heat buildup will be an issue, so machining it may be necessary. (Sawing will create a lot of heat and damage the seals which are only two inches away)."
(4/16/03)
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#9
"Once the shaft is shortened, it needs to be reshaped to match the Fiero's stock intermediate steering shaft. Although it defies description easily, inspection of the stock Fiero rack should show the desired shape that it is required. Again, heat will be an issue, so machining is most likely the best method of doing the work."
(4/16/03)
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#10
"Now to the mounting points. Both sides of the Merkur rack need modifications in order to mount in the proper position. I am going to split up the discussion into the right (passenger) and left (driver) side mods.
Again, a point of reference. Thanks to Howard Sacks for having posted these shots earlier. This is the right side of the rack, mounted in the car with the standard Fiero clamps. Note the position of the clamp in relation to the black clamps on the rack."
(4/16/03)
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#11
"Here is how the [right side of the] modified rack looks"
(4/16/03)
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#12
"Compare the pics of the modified rack to the ones of the unit mounted in the car to see how the mounting clamp fits between the compression clamps."
(4/16/03)
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#13
"So now we're to the left (driver's) side of the car. Here is a picture, again with credit to Howard Sacks, of the left side"
(4/16/03)
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#14
"The stock Merkur rack must be machined to give it a flat mounting point. If you hadn't removed the tubing previously, it must be removed from the rack in order to do this. Here are several pictures which detail the work. The goal is to make the mount point flat, and the rest round to accept the standard Fiero mounting clamp."
(4/16/03)
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#15
"I took the pics from up"
(4/16/03)
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#16
"down"
(4/16/03)
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#17
"and sideways so you can get a better idea of what it should look like."
(4/16/03)
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#18
After installing the rack there is the problem of how to power it.
With a V8 in the Fiero there is probably not room for a pump
(unless the frame is stretched), so Electro-Hydraulics (EH) is the answer.
My current info is that the Chevette did not have an electric pump.
(4/16/03)
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#19
There is a report of a 1991-95 MR2 (2.0 or 2.2L) EH system being used in a Fiero. Dark Fiero:
"I put the electric p/s pump on a relay so it would only turn on when the car was in gear, and the transmission was in rev, 1st, or 2nd.
The p/s pump is not running when you are going down the road at considerable speed."
What about coasting in nuetral? It might be better if pump ON was based on a signal from the speedometer.
"We plan to figure out how we can get the toyota steering wheel position sensor so we will have feedback steering."
ATSCO pump PN5463 is $185.
(4/16/03)
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#20
I'm told the fiero manual steering is FINE. If i can get my new `85 on the road
then i'll decide for myself.
(6/27/05)
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