OK, I got my hands on a standard Vette rackwith a date stamp of 86 on it. Yes there are differences, but nothing that would cause a problem. The two are for the most part the same. The two racks are nearly identical till you get real close and measure them. The rack gear length it self is very close and the threads are the same as the ZR1. The differences between the two racks are the dimensions between the inner tie rods. The rack is made up of different parts. The main body is the aluminum part, the hydraulic cylinder is the steel part and the steering spool. The steering spool is the part with the steering shaft and 4 hydraulic lines going to it. On the ZR1 rack the steering spool is a press in cast iron part. The standard rack has the steering spool cast into the main body of the rack and can not be removed. The cylinder on the two are identical but the bodies are very different in length. To make up for the different length of the standard rack GM used thicker bump stops on the standard rack than the ones used on the ZR1. So to sum it all up you could use your stock Fiero bump stops in your standard Vette rack and get an extra .2 of travel. That would bring the standard Vette rack up to 4.6 from 4.4. the stock Fiero rack travel is some thing like 5.
The ratio of the standard Vette rack is between the F body rack and standard 88 Fiero rack. The ZR! is by far the fastest ratio, then the F body, then the standard C4 Vette rack, then the Fiero brings the slowest ratio to the Fiero.
I may try to post some of the pics and dimensions/specs latter?
Got a call from the Machine shop "Got the wrong material. Need to reorder a new bar of molly. Will have your parts by the middle of next week" Sorry about the delay. That turns a 3 to 4 week estimate to a 5.5 week wait.
If you have any questions or comments just PM, Email or call the number I sent you on the PM I sent out. Sorry again.
Originally posted by mcaanda: He who is apparently 135 pounds, and likes the 3+ lock to lock ratio of the stock Fiero dosent.
I take it that you have got to have stock rims / tires on your Fiero. Take a set of very large aftermarket rims, ie: 17x8's w/ a 35mm offset on an 88’s for example, and see if you still think that the stock "feel" serves it's purpose. I'd bet a Super Sized Double Bacon Cheeseburger from Carl’s Jr. that you'd defer to not...
Hey, I will take you up on that. I have 19x8.5s on the front with sticky nittos and I dont complain, I dont even care. I am only 5'9" and weigh 165 so Im not some huge guy. Whats all the fuss about? Anyways, bump ------------------ Low Original Miles at 35,875!!! 19x8.5(f) and 19x9.5(r) Drifz 520b's 235/35 & 245/35 Nitto NT555s Otherwise stock for now
[This message has been edited by 1fastcaddy (edited 06-07-2006).]
Originally posted by 1fastcaddy: Hey, I will take you up on that. I have 19x8.5s on the front with sticky nittos and I dont complain, I dont even care. I am only 5'9" and weigh 165 so Im not some huge guy. Whats all the fuss about? Anyways, bump
Have you ever driven a Fiero with a fast ratio power steering system? This debate has been done many times. The bottom line is that it IS NOT just about easy steering wheel effort. The fuss is about people modifying their own car to be better for the owners own taste or needs. Some people want less effort, and some just want the car to turn like a modern sports car with faster ratio steering. If you like your car the way it is, that is cool. But if you have never even driven a Fiero with fast ratio power steering, then you should look into getting it or test drive a Nissan 350Z. Then you will know what the fuss is about. A rack alone dose not make a Fiero into a 350Z, but the steering is some what alike. When modern sports cars go back to slow manual steering then I will too............Uh no I take that back. I will never go back to stock manual steering.
Got a call from the Machine shop "Got the wrong material. Need to reorder a new bar of molly. Will have your parts by the middle of next week" Sorry about the delay. That turns a 3 to 4 week estimate to a 5.5 week wait.
If you have any questions or comments just PM, Email or call the number I sent you on the PM I sent out. Sorry again.
OK, the rack adapters I made are for an 84-94 ZR1 Vette. The rack I used is a 224HD and is listed for use with the 16 inch wheels and heavy duty Vette suspension. So any Vette rack from 84-94 will work with the adapters. It does not matter if it is a ZR1 or not. The ZR1 is just a faster steering ratio. It is also called a "sport" rack.
Are all the C4 racks the same size, i.e. length? I ask becasue I called a local guy that strips Vettes and has many used racks available. He said that the racks had many different lengths broken down like this IIRC. 84-87 88 89-94 95-96
He had a ZR1 rack but wanted $300 for it.
Can you verify any of this info or is this guy full of crap.
Just trying to get all my parts ready before the adapters and mount arrive. I dont want to get the wrong rack.
Are all the C4 racks the same size, i.e. length? I ask becasue I called a local guy that strips Vettes and has many used racks available. He said that the racks had many different lengths broken down like this IIRC. 84-87 88 89-94 95-96
He had a ZR1 rack but wanted $300 for it.
Can you verify any of this info or is this guy full of crap.
Just trying to get all my parts ready before the adapters and mount arrive. I dont want to get the wrong rack.
I will not say he is off base? I am getting conflicting specs every were I turn? I will say that the 84-87 ZR1 racks and standard racks are compatible with my adapters. I have both racks and took pics and measurements of them side by side. I do not have the other years, so I cant say why they are different part numbers. But it could have some thing to do with the different size hydraulic cylinder and rack body casting and other minor changes that do not alter the physical size of the rack, but make them incompatible for exchanging internal parts. One way to tell the compatibility of racks is the tie rods. If the tie rods work, the racks are all compatible. No way around that. So I searched for Corvette rack tie rods and found that there are three different part numbers for tie rods. http://www.ecklers.com/find.asp? And the rack rebuilding company I got my first rack from said it was compatible for 84-91. So I don't know who to believe? The racks I have here are all between 84 and 87. So If you want to be "on the safe side" get a rack that in that time frame. I would not hesitate to get a 96 rack, but I can make the adapters for them. I don't think my current adapters will work on the newer C4 racks? I will need to measure the racks to find out what is changed?
I am not being argumentative. I am just adding information to help out.
The ZR1 Corvette was made from 1988 to 1995. There were only 6,939 ZR1's made in the 6 year span. That would be a hard to find item.
Corvettes have a performance package (Z51) that I think included a faster steering rack. Could this be the power steering rack you are talking about?
OK, cool. But that only makes things more confusing I have one ZR1 rack with no date stamp, this was my first rack. I got it off of Ebay from a rack rebuilder. The next two racks I have here are not mine. They belong to another PFF member. But they have date stamps on them and are between the dates of 84-87. So Is there any real diferance between the racks? All three racks are compatable with my adapters, and if the 84-87 standard rack is basicaly the same as my 88-95 ZR1 rack that is a good thing. I wish I could get my hands on them.
I have a 1993 regular rack from ebay. If you tell me exactly what to measure, I can measure it this weekend and let everyone know if it works. PM or email me what to measure.
Beware of buying racks on ebay from seller with the ebay-store called PARTS WHSE. I bought one that turned out to be junk!! Infact Rick has it now, as I had it shipped to him directly from ebay. He was going to ship it to me in Europe to save me on the expensive shipping offered by the seller. (Rick mentioned he has 2 racks belonging to a PFF member. That happens to be me).
PARTS WHSE has been totally unresponsive to my emails asking them for a replacement as what was received is clearly no good. Dents in the hydrolic cylinder, rust that was just painted over, and some goo that is oosing from one of the hydrolic lines.
I have a 1993 regular rack from ebay. If you tell me exactly what to measure, I can measure it this weekend and let everyone know if it works. PM or email me what to measure.
Tom
Keep in mind that even with all the differences between the two racks, they both are compatible with my adapters and the travel and over all dimensions are the same. The rack also many more differences between each other but it all works out in the end. Maybe why so many part numbers from other sources?
On the driver side of the rack measure the machined part that the boot clamps to. See in the pic the part that did not get painted. Measure from the very end of the rack (not the top edge of the taper, measure the end of the rack) to the end of the boot clap surface, or in other words from the very end of the rack to the where the paint starts.
as you can see, the snap ring groove is in a different location on the boot clamp surface than the first pic. Measure were the snap ring groove is on the clamp surface. It may seem insignificant, but that extra bit of material is like a thick bump stop. the thick area after the snap ring groove is used with the thin plastic bump stops. The thinner material is used with thick plastic bump stops. That way they all have the same travel.
This is the different thickness of plastic bump stops used on the GM racks I have seen. The White one is the same as the stock Fiero and ZR1 rack. The Black one is used on the standard Vette rack. And the Blue one is the thickest and was taken out of an Intrigue. You can see that they get taller from white to blue. That is how much thicker the bump stop is inside the plastic "cup" They all have the same exact fit on the stock Fiero tie rods but different bump thickness.
Measure the end cap on the pass side, from the very edge to the end of the hydraulic cylinder. The ZR1 and standard racks are different lengths.
And last but not least, measure the total length of the rack gear with the tie rods off. And measure the rack body from very end to end (the outer edge of the boot clap on the driver side to the edge of the end cap on the pass side). And if you can measure the thread pitch and size.
If you can post pics of the racks or send them to me by email that would help too.
If you have any questions you can call me. My number is on the PM I sent out.
Those look great. I appologize, I didn't get a chance to measure my steering rack this past weekend, I was busy picking up a parts car to keep my GT on the road. I will try to get it measured as you showed this coming weekend.
Beautiful! I guess I need to start looking for a ZR1 steering rack, huh?
Still don't know how I'm gonna work the power steering pump, but one hurdle at a time. (currently a 2.8, but I want to be able to use it on a future V8 swap, too)
OK,I was told again today that they will be ready tomorrow I don't know if the boot extensions will ever be ready. They are not a necessity anyway you can use longer boots from a 2000+Caddy, so If any one wants the adapters and mount without the boot extensions let me know and I will send out the adapters as soon as I can. I have a few ready to go out today if I get a short list of people that do not want the boot extensions. If you can hold off till "tomorrow" then I will just go down my list as planed.
Sorry again for the delay. This is exactly why I need my own mill and lathe
Those look great. I appologize, I didn't get a chance to measure my steering rack this past weekend, I was busy picking up a parts car to keep my GT on the road. I will try to get it measured as you showed this coming weekend.
TG oreiF 8891, Did you ever get the rack measured?
Thats looking good Rick! I will wait for the boot extensions too. I'm still getting zero response from the ebay company that sent the bad rack. What can I do if they just do not respond? Anyway thanks Rick for all your troubles thus far!!
Originally posted by fiero-iwan: I'm still getting zero response from the ebay company that sent the bad rack. What can I do if they just do not respond?
Contest the charges on your credit card, & also go through Paypal. Be warned that you have a short period of time to do this. I have seen that rack before I moved from CA, and I will tell you that it's as jacked as Rick says / the pictures show. Im VERY suprised that they would EVER send out that rack thinking that it would "pass" for a rebuilt.
Good Luck w/ it.
Shiney stuff looks good Rick! Did you get Jim to fab those up?
Wow! Lost track of this. Rick, Do you have any more of these brackets/adapters available?
I have a few sets that are not paid for, but were asked for. If everybody that asked for a set paid for a set I would have sold all of them the first week or two, but I have not got the payment for all of them. And that is OK by me because the people that did pay do have a set ready for them and my out of pocket expense is covered. So it is all good. I will say that I am not reserving any sets for latter payment. I will send out parts to those that make a payment and they will go on a shipping list in order of payment. I do need to make more mounts and I have not got the boot extensions yet. I really hate to set a date because I don't want to brake it. But I do have several sets ready for shipment IF you don't want the boot extensions.
I hope these are reasonably clear. I don't have PIP on this machine, nor am I very good with it. So I cannot post pics for a few days. I did send the pictures to Rickady88GT (I used the email listed in his profile, hope it is valid?).
I have some measurements from a 1993 C4 steering rack: 1. Very edge of the driverside rack to the end of the boot clamp surface: 27/32" (0.85) 2. Same side, end of boot clamp surface to closest edge of boot clamp ring: 15/32" (0.47) 3. Passenger side, measuring the machined lip from the hydraulic tube to its end: 27/32" (0.85) 4. Rack length hydraulic tube end to end: 20 3/8" (20.375) 5. Overall length outer edge of bump stop to outer edge of bump stop: 27 1/8" (27.125)
I didn't quite understand what the "total length of the rack gear with the tie rods off" was, nor did I have the tie rods off. I hope the last two measurements will suffice. Sorry for the delay.
edit: regular rack (not a ZR1) edit#2: I'm getting an error with PIP so I cannot post pictures; I will be happy to email if anyone wishes to see the 1993 regular rack measurements - its much more clear than the word descriptions above. ------------------ 1988 Fiero GT Cleveland Fiero Club
[This message has been edited by TG oreiF 8891 (edited 07-05-2006).]
I hope these are reasonably clear. I don't have PIP on this machine, nor am I very good with it. So I cannot post pics for a few days. I did send the pictures to Rickady88GT (I used the email listed in his profile, hope it is valid?).
I have some measurements from a 1993 C4 steering rack: 1. Very edge of the driverside rack to the end of the boot clamp surface: 27/32" (0.85) 2. Same side, end of boot clamp surface to closest edge of boot clamp ring: 15/32" (0.47) 3. Passenger side, measuring the machined lip from the hydraulic tube to its end: 27/32" (0.85) 4. Rack length hydraulic tube end to end: 20 3/8" (20.375) 5. Overall length outer edge of bump stop to outer edge of bump stop: 27 1/8" (27.125)
I didn't quite understand what the "total length of the rack gear with the tie rods off" was, nor did I have the tie rods off. I hope the last two measurements will suffice. Sorry for the delay.
edit: regular rack (not a ZR1)
Thanks for the measurments TG oreiF 8891.
Rickady88GT, Can you use these measurements to see if this 93 rack would fit with you adapters?
I am back from a 6 day camping trip to the mountains. We took the Jeep on some off road trails. I did not notice the new replies to this thread.
As far as the measurements go, I will try to be more clear on exactly what needs to be measured. I will try to post pics of the needed measurements.
I would not recommend an electric pump for the rack unless you know enough about hydraulics to do the math. That means basically you need to figure out flow volume and pressure and other specs of both pumps to start with to see if the pump will even drive the rack. Then a system of relays and other electronics will need to be used to run the electric pump properly.
I know on the factory electric units they reduce the pump speed as you accelerate. There has to be control over this, as well as making sure you have full power steering in a parking lot situation, while not needing to run it wide open all the time the engine is idling.
Which makes me wonder, what is done on factory engine driven pumps? Do they have anything to throttle the pump, or is it solely driven off of the engine speed? If so, the most you'd ever need is whatever the engine delivers at idle, right?
I think so, your logic appears sound to me. That's what I was thinking. I am not the electronics guru, but with all the knowledge on this forum, it seems to me that someone could make a controller work off the vss signal. It could control the current to the pump so it gave none (or very little) at speed and full power under say 5 mph. I think its possible, but I am more mechanical than electronic, so I am probably not the one to test it out.
Edit: Question: Would the pump wear out to quickly if it ran all the time the car was at less than 5 mph? Does it then need a mechanism to turn on when you start turning?
[This message has been edited by TG oreiF 8891 (edited 07-23-2006).]
"Got the wrong material. Need to reorder a new bar of molly. Will have your parts by the middle of next week" 
I have one ZR1 rack with no date stamp, this was my first rack. I got it off of Ebay from a rack rebuilder. The next two racks I have here are not mine. They belong to another PFF member. But they have date stamps on them and are between the dates of 84-87. So Is there any real diferance between the racks? All three racks are compatable with my adapters, and if the 84-87 standard rack is basicaly the same as my 88-95 ZR1 rack that is a good thing. I wish I could get my hands on them.
I don't know if the boot extensions will ever be ready. They are not a necessity anyway you can use longer boots from a 2000+Caddy, so If any one wants the adapters and mount without the boot extensions let me know and I will send out the adapters as soon as I can. I have a few ready to go out today if I get a short list of people that do not want the boot extensions. If you can hold off till "tomorrow" then I will just go down my list as planed.
