Need more information on exactly what your trying to do.You could take the rotars to a machine shop and have new holes drilled for the correct bolt pattern of rims your trying to use ,but the rims should have the same offset for the fiero.Bearings????
[This message has been edited by James Bond 007 (edited 03-16-2004).]
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09:00 PM
Mar 17th, 2004
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
Are you asking if there is a wheel bearing hub assem from a Camaro or Vette that will bolt into the 88 bearing carier? For the purpose of using Chevy wheels on you 88 Fiero? I dont think so? The Fiero bearing is kind of small and only has three bolt holes to mount it. The Camaro/Vette bearings are probably larger and use four bolt holes. Then there is the axle splines, will they match the Fiero? I would get some if you find them, good luck.
I'm having trouble getting the pictures posted here, that's why I just emailed you the pictures. Now I'm having email trouble so will reply here. If you can feel free to submit the pictures I sent you. A 1992 Pontiac 6000 hub and bearing NAPA part # PBR930022KPG, has a 115 mm bolt pattern. I had a new bolt pattern drilled and new studs pressed in. The old holes were welded over and ground flat. The Fiero hub is too small for the 4.75" Corvette pattern. The black Fiero upright was machined to take the new larger bearing. Keeping the whole bearing with it's outer casting would take too much from the upright. The new half bearing carrier was made with mounting holes that match the Fiero upright. You'll have to figure the measurements yourself. I took measurements for the thickness of the 1988 Fiero rotor and the 1997 Z-28 Camaro rear disc rotor and found them to be close. They are 11 55/54" diameter. Summit has them for $115 or $26 at lawrence@nccw.net. I had to make an adapter to move the Fiero calipers out to the edge of the larger rotor. I'd suggest you just go with the Z-28 reat calipers. You'll still need an adapter, but better to keep the Camaro calipers.The pictures show the rest. The hub center piece fits the new rotors perfectly. I'm swapping the front spindles from a Camaro onto the Fiero with a crude adapter. This allows the whole Camaro front brake setup. Just consider these ideas. I take no responsibility as I don't know your skill level or any of your plans.
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04:12 PM
FTF Engineering Member
Posts: 710 From: Near Philadelphia PA Registered: Sep 2001
So let me see if I understand. There wasn't enoughf meet on the rear knuckle to open it up all the way for the 5/115 hub. So you splitt the difference and took material off BOTH the HUB and KNUCKLE. Is this correct? I've been looking for a way to go to a 5/15 patern for quite some time.
------------------ Don Hites 88 GT, Getrag 5spd, 4.9 v8 with a Delta cam and other heavy mods. 88 Coupe 5spd Duke (now under restoration)
(((So let me see if I understand. There wasn't enoughf meet on the rear knuckle to open it up all the way for the 5/115 hub. So you splitt the difference and took material off BOTH the HUB and KNUCKLE. Is this correct? I've been looking for a way to go to a 5/15 patern for quite some time. )))) There wasn't enough meat on the knuckle for the bearing retainer casting. The only maching on the hub was just the wheel stud holes re done to the Corvette/Camero pattern. This left the hub with it's original strength. By using the knuckle as the bearing carrier for half of the bearing race, eliminating half of the bearing carrier casting, I didn't have to bore out the knuckle that much. The knuckle was machined for a tight fit of the bearing race. The part of the knuckle opposite from the bolt face was machined to take the 6000 grease seal and the inner part was machined to seat the inner part of the bearing race. However, the knuckle isn't as deep as the bearing, so I had to build something to carry the rest of the bearing race. I could have cut the standard 6000 bearing casting in half and bolted it to the Fiero knuckle, but the bolt holes are in a wider circle. So I made one that uses the inner dimentions of the 6000 piece, but has bolt mounting holes to match the Fiero's knuckles. I'm not sure, but I think you can use the 6000 knuckles without this expensive machine work, if it's for a 1984-87 Fiero. I haven't done it, but I seem to recall they will fit.
I noticed in the picture of the caliper adapter, it looks like a piece of 1/4 plate rounded off. It is actually a 1/2 thick piece machined to fit snuggly against the Fiero casting. Then the other side is machined to fit the caliper. You have to make sure the caliper is aligned over the Camaro rotor and that the new mounting holes are designed to move the caliper away from the rotor's center and not just away from the original mounting holes. I think I'd just use Camaro calipers and make the adapter for them and not bother with the Fiero calipers. This whole setup gives benifits a couple ways. You can find more wheel sizes and styles in the 5-4.5 pattern. You can use the larger Camaro brakes. You get stronger hubs. You get the stronger tri pot. Camaro front spindles can be easily adapted to replace the 1988 Fiero (maybe others, too) front spindle, so you get Camaro brakes front and rear.
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03:41 PM
Mar 21st, 2004
FTF Engineering Member
Posts: 710 From: Near Philadelphia PA Registered: Sep 2001
The only maching on the hub was just the wheel stud holes re done to the Corvette/Camero pattern. This left the hub with it's original strength. By using the knuckle as the bearing carrier for half of the bearing race, eliminating half of the bearing carrier casting, I didn't have to bore out the knuckle that much. The knuckle was machined for a tight fit of the bearing race. The part of the knuckle opposite from the bolt face was machined to take the 6000 grease seal and the inner part was machined to seat the inner part of the bearing race. However, the knuckle isn't as deep as the bearing, so I had to build something to carry the rest of the bearing race.
peabody, Thanks for the pics. That is way cool!! Man have you got me confused with some of it though... Here's a bunch of questions in no particular order:
The first pic.... The top item is a used unmodified stock Fiero bearing hub with a 5x100 bolt pattern, right? The bottom item is PART of an aftermarket 6000 bearing hub with a 5x115 pattern? You got this part by pressing an aftermarket 6000 hub apart, right?
You didn't mention this, but you must have replaced the outer CV joints with the larger ones from the 6000, right? And then you machined the inboard side of the knuckle to accept the larger seal required by the larger 6000 CV joint, right?
You machined the outboard side of the knuckle to accept the outer race of the bearing that was used inside the aftermarket 6000 hub assy? By the way, what was the bearing part number inside the 6000 hub assy?
You didn't use the other half (the outer part) of the aftermarket 6000 hubs because you didn't need them?
How do you think your wheel mounting flange offset compares to stock?
quote
Originally posted by peabody:
This whole setup gives benifits a couple ways. You can find more wheel sizes and styles in the 5-4.5 pattern.
I thought the Camaro/Vette used 5x4.75, not 5x4.5?
Whew... I hope all the questions make sense!!
-Bruce at FTF Engineering
PS - Rickady, Thanks for hooking us all up with the pics!
[This message has been edited by FTF Engineering (edited 03-21-2004).]
The top picture compairs the difference between the Fiero and the 6000 hub. I had the whole hub assembly apart. The fourth picture is a custom piece I had made. The inner dimentions match the inner measurements of the 6000 casting. It would have been easier to just cut a casting in half and use it, but it's three bolt holes were in the wrong place for the fiero. You are right, outer part of axle, CV jount is 6000. All this machine work isn't needed for pre-88 Fieros. The Ceira or 6000 knuckles can replace the Fiero piece and you just use the hubs right off the shelf. The part numbers for the 1992 HD Pontiac 6000 hub is NAPA part PBR930022K PG. The axle I used shows a NAPA Part number 8527, but I'd double check that, first. (((You didn't mention this, but you must have replaced the outer CV joints with the larger ones from the 6000, right? And then you machined the inboard side of the knuckle to accept the larger seal required by the larger 6000 CV joint, right?))) Right and right. (((You machined the outboard side of the knuckle to accept the outer race of the bearing that was used inside the aftermarket 6000 hub assy?))) Yes. (((By the way, what was the bearing part number inside the 6000 hub assy?))) It was what ever was inside the assembly. THe custom bearing carrier was hard to make. Near the outer part is a groove for a snap ring and aligning the inner part with the matching inner part of the knuckle and locating the three mounting holes was tricky. I think the face of the hub is the same as the Fiero. The Camaro disc brake rotor lined up with the Fiero caliper, so the offset of the rotor must be the same too. This is easier to explain if you had the parts in your hand. I went at it for a couple rasons. Stronger hubs, bigger brakes and stronger axles. Turns out the axle is the same diameter but the ends are bigger. I've got a picture of the 6000 casting.
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09:01 AM
FTF Engineering Member
Posts: 710 From: Near Philadelphia PA Registered: Sep 2001
Originally posted by peabody: THe custom bearing carrier was hard to make. Near the outer part is a groove for a snap ring and aligning the inner part with the matching inner part of the knuckle and locating the three mounting holes was tricky. I think the face of the hub is the same as the Fiero. The Camaro disc brake rotor lined up with the Fiero caliper, so the offset of the rotor must be the same too.
OK... I think I got most of it. Thanks for the additional info.
I also have an '88 and have changed my bolt pattern in the rear to 5x4.5". I did mine a little different though by modifying an aftermarket Fiero rear bearing and making an adapter ring that fits behind the original wheel flange. Needless to say that I'm familiar with the '88 difficulties and you're right... It would have been a lot easier with a pre-88!!
So why did you need a groove for a snap ring in the custom piece you made? Why didn't you just counterbore a shoulder at the right depth from the other side for the bearing to rest against?
quote
(((By the way, what was the bearing part number inside the 6000 hub assy?))) It was what ever was inside the assembly.
Heh... I figured that much out. I was kinda hoping that maybe you wrote it down somewhere while you had the whole thing in pieces?
this is pretty interesting; I am doing the same thing or sort of, anyway, and am finding some different things happening with how parts fit, so I am posting this just so that people will be aware that there may, at least, be variations and to check clearances and sizes and so on. I am using the Pontiac 6000 upright but found there were TWO different types; one was heavier duty or something so that was the one I picked. Maybe that is why I needed to get some machining done. I am going to the std Chev 4 3/4" bolt circle so am putting the S10 rear bearing in. The 6000 upright is VERY similar to the fiero (mine is an 85) but the hole is way bigger and the 3 bolts are (ever so) slightly farther out. So I had to machine the big bearing hole a tad and then get the 3 bolt holes stretched a bit to properly lock into the S10 bearing. I will have to reload my pix here; I changed 'puters so don't have the program anymore. The fronts are fairly highly modified fiero spindle assys; with camaro STUB axles installed into them (press fit and weld) and I am now using turned down camaro hub assy's (similar to the Walt Zettner idea for turning down a fiero hub) and mounting Vette 13" rotors on them. The stock camaro spindle is HUGE compared to the stock fiero one.
I am finding - very VERY much to my surprise - that there is NOT the great selection of wheels avail anymore for the 4 3/4" bolt circle; not nearly what there used to be. So for a specific offset, you may NOT find what you are after. I recommend you check out wheel (and offset) availability before assuming you can simply find what you want - it is not working that way for me in that area at ALL!!!! I will post pix if that will help but I have to go find out how to do it here again. my 2 cents; hope it helps someone.
ok figured out/remembered how to post........ oh well. the first pic is of the 6000 and the fiero uprights; just to compare. In most respects they are identical but the holes are quite different!! next is an S10 bearing assy; it has the std chev camaro 4 3/4" bolt pattern but notice the 'shoulder' that will fit into the upright. It is SLIGHTLY larger dia than the 6000 bearing (pic to follow to compare the 6000 to the fiero bearing!) and the fiero and 6000 bearings; to show the sizes; notice that neither has a 'shoulder' - they both fit 'full length' into the upright.
[This message has been edited by fiero308 (edited 03-22-2004).]
to continue; and hoping this might help someone; this pic shows the modified/machined 6000 upright; you can see where there is a small amt removed to allow for the slightly larger diameter S10 bearing to fit into the main hole and the bolt holes have been elongated a bit; this is OK as the bolts go thru from behind into the bearing; NOT from the bearing into the upright as with the stock fiero....... the stock 6000 WAS like that, but not anymore...... this is shown with an S10 bearing. It is a nice tight fit. I would only trust a very good machine shop to do this kind of work... next is my front spindle; I got a camaro assy and had the axle stub machined out of it,then press fit into the fiero spindle assy. Then welded both in and out. The stock setup is a total interference fit, but it is put together with a BIG sucker of a press........ then I had the camaro brake rotor 'parted off' so that only the hub assy remains. This isn't quite finished but you get the idea. and then install that using the (nice!) larger camaro bearings onto the modded spindle assy; and then put on the 13" vette rotors and try the Wilwood caliper for clearance........ (this is looking down into the inside of the wheel.....) the wheel to caliper clearance is REALLY small but that is enough!!! now to make a bracket....... a project in the works. The modded camaro hubs are still goig to be turned down a bit more; I should have both sides within a wk. Note that when you do this you need longer studs too as the slip on rotor 'eats up' a bit of length there. so more to come if it is of any help. NOTE; a disclaimer is probably in order here. I want to say that this is just what I am doing and I have been in the mech design business for a LONG time; I do not recommend others to do this; it is still a work in progress........ I work very closely with a VERY competent machine shop and have a certified and VERY experienced welder do all the work even tho I have been welding for years etc etc etc. Not for just anyone to do and NOT to be done on a budget!!!!
sorry about the double posting; it hung and hung and hung and finally it went thru. I thought only one would appear and not sure why more than one is here......?
I tried to delete one but it wouldn't let me. Only forum leaders..
so assume that there is one for each side, I guess......
next is an S10 bearing assy; it has the std chev camaro 4 3/4" bolt pattern but notice the 'shoulder' that will fit into the upright. It is SLIGHTLY larger dia than the 6000 bearing.
308, Nice work you got going there! Thanks for the pics. I guess I should have taken pics of my project along the way, huh? I was in too much of a hurry to get the car on the road!!
So you're using the S-10 instead of the 6000 hubs because you wanted 4 3/4 and not 4 1/2, right?
Why didn't you just leave the 6000 knuckle alone and machine some of the shoulder off the back of the S-10 hub? You would have still machined the knuckle to slot the mounting holes, but that's the easy part. Also, does the S-10 knuckle have a matching shoulder in it that mates with the S-10 bearing?
And about the front...
quote
next is my front spindle; I got a camaro assy and had the axle stub machined out of it,then press fit into the fiero spindle assy. Then welded both in and out. The stock setup is a total interference fit, but it is put together with a BIG sucker of a press........
I'm not very familiar with the pre-88 cars... Are you saying that the stock spindle is PRESSED into the front knuckle? No welding holding it in?
I found the same thing you did with wheel availability. The 4 3/4's are out there, but not nearly as prevalent as the 4 1/2. My conversion would have actually been easier to go 4 3/4's, but I wanted a wider choice of wheels so I went 4 1/2.
I ended up with Mille Miglia II wheels. Fronts are stock 5 x 100 and rears are 5 x 4 1/2 and it looks like this:
-Bruce at FTF Engineering
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10:27 AM
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
I went with 4 3/4" mostly because of years of being a chev (camaro etc) fan and assuming (wrongly now) that there were zillions of wheel choices avail. Not so. The 4 1/2" is Ford and Chrysler (I think) and with the more recent popularity of the mustang there are some very nice patterns avail. I don't know what GM piece would be 4 1/2" off the top of my head.
The big prob is finding a wheel I LIKE that also has the backspacing I NEED and a price I can AFFORD....... I am getting LOADS of cooperation from wheel shops that can custom make wheels for me............ at $500 a pop and you wait till they get around to it....... So I am looking for 'reasonable' wheels. Right now I am using the 16" IROC rims for sizing and assy; I may switch to 17" at some point.
I didn't machine the hub, or bearing, assy because it is a wear and maintenance item that you will have to replace someday and then you would have to repeat that process. The S10 front knuckle is not ANYthing like the fiero one; I have one in my garage and looked at it last nite; it would require a TON Of work compared to the bit for the 6000 piece. The rear is almost as big as the camaro unit; see the pix...... I think, after looking over the camaro spindle assy with the m/c shop, that the spindle axle stub MAY (guessing a bit after looking at a rusty piece) have been pressed in. With a VERY heavy press; but today (hmmm?) it might also be a single cast steel piece that was put into a very large dia lathe and turned. THAT seems like it would be a slow process tho; for a HIGH production part, so that is why I am guessing at the press - a very tight interference fit into the knuckle. ANYway, we drilled it out and press-fit the larger axle stub into the fiero knuckle assy. left to right (all stock assy's): camaro, S10 and (puny) fiero so that is where I started thinking about the abuse factor etc that is on that little axle stub. Another pic shows the fiero and camaro axle stubs: (guess which is which) and another view shows why you can't simply use another spindle assy. The camaro and the fiero again. Maybe this is all overkill; I had heard concerns about axles being weak and so on altho I can't say I have ever heard of any reports of BREAKAGE (of front axles) so it may not be necessary, but I had it in mind to make things ALL the way I wanted and having really solid braking was a big deal. hope this helps!
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05:05 PM
Mar 24th, 2004
FTF Engineering Member
Posts: 710 From: Near Philadelphia PA Registered: Sep 2001
The big prob is finding a wheel I LIKE that also has the backspacing I NEED and a price I can AFFORD.......
I didn't machine the hub, or bearing, assy because it is a wear and maintenance item that you will have to replace someday and then you would have to repeat that process.
we drilled it out and press-fit the larger axle stub into the fiero knuckle assy.
Hey 308,
Thanks for the additional pics. That does help.
Yeah, I feel your pain on finding the right wheels. Price, backspacing, width, bolt hole location... and not to mention that you actually have to LIKE them! Been there. I had actually originally wanted SSR Integrals, but they were way more expensive than the MM II's and I wasn't sure that the whole project was even going to work. I figured I would get the MM II's first and then after confirming that everything fit and my custom wheel bearings weren't going to explode into a bazillion pieces, I could always change over to the SSR's at some future date.
I gotcha about machining the spindle instead of the hub. Now you can replace the S-10 hub with another off the shelf S-10 hub if you ever need to.
So when you pressed the spindle into the knuckle, did you machine it with a shoulder or clear through? Do you have any pics of those two peices before you joined them? By that, I mean, do you have pics of the stub that you cut out of the Camaro BEFORE you welded it into the Fiero spindle?
The reason I ask is that I (personally) wouldn't want to put my life on the line for the quality of a weld alone. It may just be me (and my welding skills), but I would be much more comfortable with a design such that even if the weld failed completely, the whole thing wouldn't be able to go too far.
Something like putting a shoulder on the stub and matching counterbore in the spindle and then pressing the stub in from the BACK side of the spindle. That way even if the weld failed, it couldn't pull completely through the hole and leave the car because of the shoulder. And in addition, the bearing tightened onto the stub should pinch everything together and keep it relatively close to where it belongs. (Did that make sense?)
hi Bruce sometimes you can go thru your car and find things that almost make the hair on the back of your neck stand up; it seems so flimsy and fragile. I try to keep a 'weakest link' point of view in mind whenever I am thinking of doing ANY work of any sort.... and then I make DARN sure I am at least twice as strong as that in my new piece/repair/work etc. I have a pic of the old camaro spindle stub only and the (removed) fiero stub: you note the dia of the base of the camaro stub axle (that will go into the fiero knuckle)...... it is larger than the stock fiero axle. next is the fiero knuckle and the camaro stub axle; you can see (maybe) the hole and axle diameters for a comparison. The hole had to be opened up to match the new axle being pressed in; and I requested a strong interference fit. So the mechanical loading will be all along the length of the axle stub (as it should be) and the welds are (also as they should be) acting as a retainer and not as a strength item. shows those two pieces and this is the more or less finished item: and the backside showing the welding: you asked about the S10 setup: I only had them machine enough to accept that short 'shoulder' piece; the rest is just the right size for the balance of the bearing; there was no reason to machine the whole depth of the upright and I figured that this would improve the support for the bearing. I think this is posted already but here it is again; you will see inside the large hole that there is a 'lip' - that is where the bit was removed for the s10 shoulder. hope this helps. You should be aware that you will ALSO have to change the splined DRIVEN axle piece that protrudes thru this S10 bearing...... it isn't over YET.........
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09:19 PM
FTF Engineering Member
Posts: 710 From: Near Philadelphia PA Registered: Sep 2001
hi Bruce sometimes you can go thru your car and find things that almost make the hair on the back of your neck stand up; it seems so flimsy and fragile. I try to keep a 'weakest link' point of view in mind whenever I am thinking of doing ANY work of any sort.... and then I make DARN sure I am at least twice as strong as that in my new piece/repair/work etc.
Heh... Yeah, I know. I'm a belt and suspenders kinda guy myself and am well known for over-engineering.
So you DID put a shoulder on the stub axle, right? You just put it on the wrong side! I'm just kidding. Those welds look great and I'm sure it will be fine. I just would have wanted SOMETHING to be in compression instead of having everything, including both welds, in tension.
Hey, have I mentioned that adapting a stub axle into the front suspension is a really cool idea?
I wonder if the '88 could be modified in a similar manner... I got way lucky and was able to find my front wheels with the correct offset in 5x100 which enabled me to do my wheels without having to change the front bolt pattern. That's one of the reasons I did 4 1/2 instead of 4 3/4 bolt circle. Changing the bolt circle on the front of the '88's is a tricky proposition due to the unique bearing hubs. If I could get away from the hub style bearing completely and just stuff a chopped out stub axle into the hole in the knuckle though... That opens up some possibilities I hadn't thought of before!
quote
You should be aware that you will ALSO have to change the splined DRIVEN axle piece that protrudes thru this S10 bearing......
What do you mean by that? I assumed the S-10 used a different spline than the Fiero, but so does the 6000. Are you saying that the 6000 and S-10 are different?
actually, with steel, when you get to maximum yield points, it is strongest in tension, not compression. That is why they do those little stress/strain tests by pullling a sample to destruction (yield). But this is not a situation where that will play a part. The steel is being loaded along its full length and the welds are fairly low-stressed items here; the 'moment' caused by the radius of the tire will always put a 'lateral' load on that stub axle, and while it Will have to hold against pure radial loading due to mass of the wheel, the moment (leverage, if you prefer) effect caused by the wheel radius will always be the big factor. Plus, when that sort of thing is happening the car probably is into body roll as well, which further angles the axle and wheel etc etc etc. At any rate, I am not worried about it. re: splines: the ONLY part of the 6000 that gets used is the upright. The bearing, which has the wheel studs in it, is for an S10 and it is the 4 3/4 bolt circle; and THAT inside spline has to have a matching OUTside splined axle end (to drive it). so the "tip" of the end CV joint has got to be made to match the S10 and the "Ball" or inner, of the same CV joint has got to be made to match your axles. It is actually pretty easy; as in, the parts are interchangable and it fits and will work. Just dont try this at home, kids........ there are a LOT of parts in there and they only fit ONE way!!!! So take it to a shop that does that, explain what you want and they can do it pretty quickly. I have some pix but can't seem to put my hands on them right now. will post them if/when I find them.
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10:46 PM
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
FTF E, you say that it is hard to change the bolt patern on the front of the 88? Seems like it would be easy to just redrill a new patern on the stock 88 front hub. The flang is Much larger than the rear hubs. I have seen some one do it but I dont know if that was done on the smaller rear hubs or on the larger front 88 hubs?
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10:48 PM
sspeedstreet Member
Posts: 2306 From: Santa Maria, CA Registered: Dec 2002
He did manage to get a 5X130 pattern on the fronts, but it looks iffy to me. I have a set of Boxster wheels I'm going to use, but with larger diameter hub flanges.
Neil
------------------ 1988 GT, 5-speed, white, beechwood leather, trying to get my 3.4 DOHC put together.
[This message has been edited by sspeedstreet (edited 03-24-2004).]
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11:36 PM
Rickady88GT Member
Posts: 10648 From: Central CA Registered: Dec 2002
I'd like to say thanks to everyone for the good info in this thread.
I plan on running the 115mm pattern with a-body uprights on the rear sometime in the future, but wanted the same pattern up front to make it easy to find matching rims. I was looking into the Held Motorsports front knuckles that use cartridge-type bearings, but they use the smaller Fiero 110mm bearing cartridges. Wondering if there is enough material on the Held units to machine them for 115mm a-body cartridges?
sspeedstreet: I think Michael Smith has a page showing a swap to Porsche wheels; might not be boxster but there is some good info. I think he was working with an 88, too.
FTF E, you say that it is hard to change the bolt patern on the front of the 88? Seems like it would be easy to just redrill a new patern on the stock 88 front hub. The flang is Much larger than the rear hubs. I have seen some one do it but I dont know if that was done on the smaller rear hubs or on the larger front 88 hubs?
Rikady,
The problem with the fronts is that if the new pattern is too small, you run into the existing holes and if the new pattern is too big, you run out of flange.
I was changing to a 4 1/2" circle... It's just over a half inch bigger than the original pattern and uses about half inch diameter holes for the new studs. This means that part of the new holes is at the same radius as the old holes and there just isn't enough virgin material on there to put all five holes.
I remember MWS's Boxter adaptation. I helped with the engineering on this project. As a matter of fact, on that page when he says:
quote
"Concern was expressed by some people about the metal being so thin at the flange edge of the hole for the stud. (there's a scant 3mm of metal at the flange edge!!)
Haha!! That was me... I'm "some people" Like I said, I'm known for over-engineering... I thought his 130mm holes were too close to the flange edge, but he ran some tests and it seems fine. So, 130mm works. 4 3/4" might be OK, but 4 1/2" is just to similar to the original hole locations that it doesn't work. Does that make more sense?
I also helped Michael with the rears when it came to understanding the bearing assembly, and the custom rear wheel bearings that I made for my car use the same basic idea that Michael came up with a bunch of years ago. (I like to think that mine turned out a little better because I learned from the first ones, but it's probably just the over-engineering talking again)
Hey TimGully,
You want 115mm:
quote
Originally posted by TimGully:
I plan on running the 115mm pattern with a-body uprights on the rear sometime in the future, but wanted the same pattern up front to make it easy to find matching rims. I was looking into the Held Motorsports front knuckles that use cartridge-type bearings, but they use the smaller Fiero 110mm bearing cartridges. Wondering if there is enough material on the Held units to machine them for 115mm a-body cartridges?
I'm not sure I understand what you're planning to do here. Something doesn't make sense...
If you have an '88, then you can't use the a-body uprights on the rear, and if you don't have an '88, then you don't have cartridge bearings up front. Am I missing something here?
-Bruce at FTF Engineering
[This message has been edited by FTF Engineering (edited 03-26-2004).]
I'm not sure I understand what you're planning to do here. Something doesn't make sense...
If you have an '88, then you can't use the a-body uprights on the rear, and if you don't have an '88, then you don't have cartridge bearings up front. Am I missing something here?
-Bruce at FTF Engineering
Yep, you're missing something. I'll explain... The Held Motorsports front spindle - http://www.heldmotorsports.com/drop.htm - (maybe I should say knuckle) is completely different. It DOES use cartridge bearings from a Fiero rear. I was just wondering if they left enough material so you could run A-body Heavy Duty 115MM bolt circle bearings in 'em.
I have a pre-88 car, and have the a-body HD bearings/knuckles & outer axles sitting on my garage floor right now. They should bolt right in when I'm ready to swap.
just a thought here, after having gotten into this mess a bit (the swap, not the thread ) refer to pic........ ........ I would suggest a couple of things as prelim work BEFORE making any decisions, that is, if MONEY has any bearing on your decision making process... Ask around a bit what various bearings cost. Both cartridge and conventional (if that is choice for you). I assumed they would all be in the same ballpark, and that isn't necessarily true!!! And guess how Murphy's Law will figure in on your choice......... ......... yup. You will invariably get the most expensive ones....... So if I had a choice here, I would try to stay AWAY from the cartridge bearings if at all possible. I don't think they are the greatest design or system and they are VERY expensive, or at least some are. And of course they are totally non-serviceable...... but check on some prices..... if you are going to do a conversion, why not pick your parts by price, rather than (like me) by bolt circle? You will likely find just as many wheels avail at 115 or 4 1/2" or even 100mm for that matter as any other bolt circle, so at least think about it and save yourself a few bucks for free!
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02:20 PM
FTF Engineering Member
Posts: 710 From: Near Philadelphia PA Registered: Sep 2001
Yep, you're missing something. I'll explain... The Held Motorsports front spindle is completely different. It DOES use cartridge bearings from a Fiero rear. I was just wondering if they left enough material so you could run A-body Heavy Duty 115MM bolt circle bearings in 'em.
Tim,
Ah HA! Yes, that clears it up. I know nothing about Held's parts... Makes sense now, thanks.
Unfortunately though I don't think there's enough meat to redrill the rear flanges for 115mm.
quote
Originally posted by fiero308:
if you are going to do a conversion, why not pick your parts by price, rather than (like me) by bolt circle? You will likely find just as many wheels avail at 115 or 4 1/2" or even 100mm for that matter as any other bolt circle, so at least think about it and save yourself a few bucks for free!
308,
I'm in the same boat you are... I've already DONE my swap. Just continuously looking for better ideas. To be honest, I'm not a big fan of the cartridge bearings either and I really like your idea about converting to an old style (servicable) spindle design with tapered rollers!
Here's a bunch of questions in no particular order:
I was kinda hoping that maybe you wrote it down somewhere while you had the whole thing in pieces?
in that area at ALL!!!!
I'm just kidding. Those welds look great and I'm sure it will be fine. I just would have wanted SOMETHING to be in compression instead of having everything, including both welds, in tension.
) refer to pic........
