1992 Z/34--Euro 3.4 steering rack gear ratio/steering feel

[White93z34]

So what about different tightness levels? some racks have high effort steering where others of the same turn do not?

[Crazy K]

So what about different tightness levels? some racks have high effort steering where others of the same turn do not?

 

I see that racks tend to feel tighter and need more effort as the number gets lower, but I can't specifically account for what you are describing... but I can put out some educated guesses for differences that make the same rack feel different:

tire width and grip, wear (stiffness) of joints in the system, the powersteering pump's actual pressure output....

 

a curiosity to me as that my 93 vert's powersteering was always kind of hard, harder than I like... the question is what changes can be made to overcome that?

[Galaxie500XL]

From what I recall in my long search for NV7 power steering pumps, you're right..the '96 LQ1 GTP did have the NV7, which should also mean it had a 2.25 ratio rack...assuming it hadn't been replaced by the previous owner..

 

Yeah, I'm almost positive my 96 GTP was 2.25 and NV7. I remember going to check it one evening after reading one of the multiple threads that there have been on this topic.

[Schurkey]

I further state that ALL racks are the same rack, they all use the same housing with the pinion gear being the difference. I beleive that the rack's "linear gear" is the same between all racks, thus any rebuilder or even you may just have one or two gears made new to install, making any rack whatever they want.

A larger or smaller pinion gear would require different spacing to the rack gear; similar to rear axle gears where, as the pinion gets larger, the ring gear has to become thinner, or a different carrier is needed to adjust the spacing.

 

I don't understand how the spacing is adjustable on a rack-and-pinion steering gear, unless the rack gear is made thinner to match a larger pinion. If there's another method, I'd love to hear about it. Perhaps eccentric sleeves that the pinion is mounted in???

 

So what about different tightness levels? some racks have high effort steering where others of the same turn do not?

 

I see that racks tend to feel tighter and need more effort as the number gets lower, but I can't specifically account for what you are describing... but I can put out some educated guesses for differences that make the same rack feel different:

tire width and grip, wear (stiffness) of joints in the system, the powersteering pump's actual pressure output....

All of the things you mention will affect the perceived stiffness of the steering gear, but only indirectly. If a rack-and-pinion system is tuned the same way a recirculating-ball steering gear is tuned, there's an internal torsion bar. A thin bar makes for easy steering, a stiffer bar makes for stiffer steering.

[Galaxie500XL]

Well, steering feel is a bit subjective..what would help would be to compare yours to another car like yours...hard to do, when our cars are as old as they are.

 

However, if there are no issues with the rack itself, I'd wonder if you either have a restriciton in the power steering line, or, the pump is getting tired and the output pressures/fuid volume from the pump isn't what it used to be...OR, seals inside the rack itself are leaky, and you're losing pressure inside the rack-since that would be an internal pressure leak, everything would look perfectly normal from the outside, because you wouldn't be losing any fluid. I had a similar problem years ago with my wife's Mustang, but in that case, there was a noticeable difference in steering effort steering to the left compared to steering right.

 

I see that racks tend to feel tighter and need more effort as the number gets lower, but I can't specifically account for what you are describing... but I can put out some educated guesses for differences that make the same rack feel different:

tire width and grip, wear (stiffness) of joints in the system, the powersteering pump's actual pressure output....

 

a curiosity to me as that my 93 vert's powersteering was always kind of hard, harder than I like... the question is what changes can be made to overcome that?

Edited February 8, 2013 by Galaxie500XL

[Schurkey]

Spun the steering wheel of the '92 Euro 3.4, the silly thing goes 2 1/4 turns lock-to-lock. So much for TGPs (only) having the 2 1/4 rack.

 

I'm going to fire up the '93 tomorrow, and see if it's the same.

The '93--which is ALSO a Euro 3.4, just like the '92 except one model year newer, has a 2 1/2 turn rack. Go figure.

 

I bought the '92 with under 6,000 miles and six months on it; but the '93 came to me with 110K and twelve years. It's possible that the steering gear had been replaced; although I have no evidence either way.

 

IF (big IF) the rack on the '93 is original, I can only say that I have no idea why a '92 would get less steering-wheel travel (2 1/4 turns) than a seemingly-identical '93 at 2 1/2 turns.

 

I also don't have part numbers for ordering a new or a rebuilt 2 1/4-turn rack. APPARENTLY the aftermarket has consolidated part numbers, and all they supply is the 3 1/8 and the 2 3/4 turn racks--if the ACDelco guide represents the "soft suspension FE1" and the "Not FE1" aftermarket parts-catalog options.

 

 

 

 

WHAT limits steering travel on the first-gen W body? Does the steering gear (Rack and Pinion assembly) have internal stops, or are there external stops perhaps on the strut/knuckle and lower control arm like was used with '64--'72 GM "A" bodies? I'm gonna have to crawl under and investigate this--if the steering stops are EXTERNAL, the lock-to-lock turns may not be a proper way to judge the steering gear ratio.

[Galaxie500XL]

Here ya go...from my Alldata account for my '95 Cutlass:

 

STANDARD: P/N 26046144

 

SPORT: P/N 26044830

 

VARIABLE/NV7: P/N 26047207

 

Not sure what the difference in lock-to-lock is, if any between the "Sport", and NV7 racks...I do know my NV7 rack IS 2.25 turns lock to lock.

 

While these part numbers are for my Cutlass..it's the same rack your GP gets, right?

 

That help?

 

PLEASE! I'd just love to have a GM part number for the TGP rack with the fastest ratio.

 

I'm going to assume that a power rack-and-pinion system uses a torsion bar just like the recirculating-ball style steering gears, a stiffer torsion bar produces less power assist, but better road feel (firmer steering). I wonder if the torsion bars are different between the FE1 and Non-FE1 racks. Do the steering gears show different internal valving in the parts manual? Different part numbers and tooth count for the rack gear and/or the pinion gear?

 

What are the chances that--just like the recirculating ball steering gears--there's a way to mix and match parts from various FWD rack and pinions to achieve better-than-stock ratios and steering stiffnesses? Maybe the rack and pinion from another model drops into a W body with beneficial results?

 

 

 

As a side note, AC-Delco reman racks as sold and described on Amazon show that the "soft-ride FE1" suspension gets a rack with 3 1/8 turns lock-to-lock, while the "Non-FE1" rack has 2.75 turns. That's about a quarter-turn more than what's been described on this thread.

 

ACDelco 36-16347 (FE1)

http://www.amazon.com/ACDelco-36-16347-Steering-Assembly-Remanufactured/dp/B000EQVVH6/ref=au_pf_ss_10?ie=UTF8&Make=Chevrolet|47&Model=Lumina|465&Year=1992|1992&carId=010&n=15684181&s=automotive

 

 

ACDelco 36-16348 (Non-FE1)

http://www.amazon.com/ACDelco-36-16348-Professional-Steering-Remanufactured/dp/B000EQR2QU/ref=wl_it_dp_o_pC_S_nC?ie=UTF8&colid=31ORN63IXRW6M&coliid=I25XQUI65NFZE0

 

 

Those are the only two AC Delco racks that Amazon shows for my vehicle, and it compares with NAPA and Carquest--both of them specify "FE1" and "Non-FE1" as the only choices.

[Schurkey]

Here ya go...from my Alldata account for my '95 Cutlass:

 

STANDARD: P/N 26046144

 

SPORT: P/N 26044830

 

VARIABLE/NV7: P/N 26047207

http://www.napaonline.com shows ALL THREE of those numbers crossing to their # NRP-22142.

http://www.napaonline.com/Catalog/BuyersGuide.aspx?LineCode=NRP&PartNumber=22142

Lumina, Monte Carlo, Regal, GP 1994--1996

 

For whatever it's worth, this part number has been "upgraded" with a "new and improved" lower bearing:

https://partimages.genpt.com/partimages/1230215.pdf

 

Not sure what the difference in lock-to-lock is, if any between the "Sport", and NV7 racks...I do know my NV7 rack IS 2.25 turns lock to lock.

 

While these part numbers are for my Cutlass..it's the same rack your GP gets, right?

 

That help?

Not so much, unless I go to a GM dealer and see if these are still available, or see if Carquest shows different interchanges. The aftermarket seems to have abandoned us. THANK YOU for looking up those numbers. I appreciate the effort you made.

[Galaxie500XL]

Glad I could be of some help...that's what it's all about. I googled those P/N's...looks like a couple of people, including GMPartsgiant say they have it...but they're not cheap.

 

www.napaonline.com shows ALL THREE of those numbers crossing to their # NRP-22142.

http://www.napaonline.com/Catalog/BuyersGuide.aspx?LineCode=NRP&PartNumber=22142

Lumina, Monte Carlo, Regal, GP 1994--1996

 

For whatever it's worth, this part number has been "upgraded" with a "new and improved" lower bearing:

https://partimages.genpt.com/partimages/1230215.pdf

 

 

Not so much, unless I go to a GM dealer and see if these are still available, or see if Carquest shows different interchanges. The aftermarket seems to have abandoned us. THANK YOU for looking up those numbers. I appreciate the effort you made.

[Crazy K]

the steering stop is in the rack. I've tested the same racks on and off a car.

 

there is a "bridge" that presses the gear turned by the steering wheel against the rack. It is supposed to be at a preload of "tight" minus 120 degrees. This may make it possible for the same rack guts to be used by any gear, and in addition, the gear cuts are spherically cut, but I will have to get some pics to better explain...

 

 

 

I did some more field research.... there are also 3 and 1/8 turn racks. found two, both from base model hell (95 FE1 base regal sedan, 91 FE1 base CS sedan) YUCK!!!!!

[jman093]

www.napaonline.com shows ALL THREE of those numbers crossing to their # NRP-22142.

http://www.napaonline.com/Catalog/BuyersGuide.aspx?LineCode=NRP&PartNumber=22142

Lumina, Monte Carlo, Regal, GP 1994--1996

 

For whatever it's worth, this part number has been "upgraded" with a "new and improved" lower bearing:

https://partimages.genpt.com/partimages/1230215.pdf

 

 

Not so much, unless I go to a GM dealer and see if these are still available, or see if Carquest shows different interchanges. The aftermarket seems to have abandoned us. THANK YOU for looking up those numbers. I appreciate the effort you made.

 

The aftermarket never abondoned us as It never made specific racks to begin with. This goes for all car lines. Aftermarket is all generic parts just meant to be a working replacement. Even the new ACDelco replacements ones will have the better pinion bearing in it, not just the aftermarket ones. That is referring to the old problem many of us had of the pinion falling apart and the rack would get a very large amount of play in it. There was a recall, but GM only recalled a small percentage of the cars that had the problem. Any replacement should have a good bearing now. The ACDelco ones, if looked up properly for your car (usually a dealer can look it up by vin), is the correct gear as far as ratio, Lock 2 Lock, NV7, etc, that came from the factory. They are however, expensive. I priced mine out on my GTP because it had the failed pinion bearing, and the NV7 2.25 L2L (again I'm almost positive it was 2.25) I needed was something like $500 I believe. Also, the ACDelco ones even though correct for your car, may have a different part number than what ALLDATA shows.