Real tech discussion on design, fabrication, testing, development of custom or adapted parts for Pontiac Fieros. Not questions about the power a CAI will give.
Stock fiero size spline stub:
Stock G6/F40 pline stub:
Large 33 spline common to many FWD full size cars:
Thickest is easily the large format 33 spline stub. I do not have a bearing to measure for this one, but here are some pictures/measurements for the S10 wheel bearing:
Here are some dimensions from an 88 upright:
The S10 bearing protrudes about 1" into the upright and has 2 stepped surfaces. The hole in the 88 upright is too small for the bearing to fit, but the OD of the leadin taper is large enough to accept the smaller of the 2 stepped surfaces. So one way to upgrade would be to bore the 88 upright to accept just the smaller stepped portion of the bearing and then machine an adapter ring to space the bearing out from the upright (really just to close up the open space) and to change the bearing bolt pattern. Doing so would require slightly longer axles and brake caliper adapters, but those shouldn't be much of an issue.
Now the question is can the same be done for the large format 33 spline wheel bearing...
There's why this won't work. Trying to use GM-application bearings. Someone get hold of a bearing catalog, and find one with a 1.374" I.D. and a 2.798" / 3.264" O.D.
If it doesn't exist, send Timkin an e-mail.
The bearing catalog is online, that is where I got the specs from page 1. I wish I could remember what website I used for that. I'll have to do some searching around again.
I think I may just go back to the early year cradle in my car. The 88 rear has been a nice upgrade to drive around on, but I think I can see greater reliability with the large parts...
Now, i wonder what it'll take to get the large 33 (I'm guessing from like devilles, etc) into a 6000 upright, unless that is the same?
Atilla the Fun wrote:There's why this won't work. Trying to use GM-application bearings. Someone get hold of a bearing catalog, and find one with a 1.374" I.D. and a 2.798" / 3.264" O.D.
If it doesn't exist, send Timkin an e-mail.
You accomplish a lot more when you keep an open mind and strive to find a solution vs. just saying stuff won't work w/o any research to back it up.
Every Timken calalog you could want are located here: http://www.timken.com/en-us/products/pa ... alogs.aspx
Jinxmutt wrote:The bearing catalog is online, that is where I got the specs from page 1. I wish I could remember what website I used for that. I'll have to do some searching around again.
I think I may just go back to the early year cradle in my car. The 88 rear has been a nice upgrade to drive around on, but I think I can see greater reliability with the large parts...
Now, i wonder what it'll take to get the large 33 (I'm guessing from like devilles, etc) into a 6000 upright, unless that is the same?
One of the larger format 33 spline axles were from a 97 Seville. The bearing for that application is 513121 and the larger pontiac 6000 one is 513016K. From looking at all the listed dimensions, it looks like the larger 33 spline bearing has the same flange pattern to the upright, but the center bore will have to be enlarged from 3.55 to 3.59. Once that is done it will bolt right on and all the other dimensions are same between them.
I don't know the diameter or spline count, but the A-body HD outer joints are substantially larger than the Fiero manual transmission and A-body light duty outer joints (same). I'd say break one of those before you worry about the 33 spline Caddy outer joints.
The wheel bolt pattern on those large bearings is 5x115 also...
The Dark Side of Will wrote:I don't know the diameter or spline count, but the A-body HD outer joints are substantially larger than the Fiero manual transmission and A-body light duty outer joints (same). I'd say break one of those before you worry about the 33 spline Caddy outer joints.
The wheel bolt pattern on those large bearings is 5x115 also...
So you're suggesting going with the 1.251" option?
The Dark Side of Will wrote:I don't know the diameter or spline count, but the A-body HD outer joints are substantially larger than the Fiero manual transmission and A-body light duty outer joints (same). I'd say break one of those before you worry about the 33 spline Caddy outer joints.
The wheel bolt pattern on those large bearings is 5x115 also...
So you're suggesting going with the 1.251" option?
The 1.251 dimension above is the G6 outer. I'm talking about the A-body (Pontiac 6000) HD bearing and outer, which may or may not have the same spline count, but is definitely not the same part.
If machining of the knuckle is going to be required, or considered as a possible solution, has anyone considered machining the knuckle to accept a bearing that doesn’t use a hub/bearing assembly? Or making a bearing adapter bracket to accept just a bearing?
That way changing the bearing would be the same as with most cars where you press out the hub and bearing and back in with the new. This should take care of your knuckle meat issue.
If you don’t have the depth you need you can make a knuckle extension that bolts into the existing threaded mounting holes.
I’m going to look into this sometime in the next three months. If it works I’ll post my solution adapting S10 hub with 5x120.7 bolt circle so I can use Corvette rims.
P.S. Should I just sign retard or nothing at all? I'm going to go with nothing.
I know this doesn't apply to my original post, but I found out today that the 94 transport/lumina/silhouette vans used the large 33 spline outers, just like the caddy did. That would be another source for the large hubs.
Jinxmutt wrote:I know this doesn't apply to my original post, but I found out today that the 94 transport/lumina/silhouette vans used the large 33 spline outers, just like the caddy did. That would be another source for the large hubs.
Another somethin' somethin' great to salvage from those vans.
Jinxmutt wrote:I know this doesn't apply to my original post, but I found out today that the 94 transport/lumina/silhouette vans used the large 33 spline outers, just like the caddy did. That would be another source for the large hubs.
Interesting. I'll have to snag some of those knuckles and take a look. The later U-Van knuckles with 11" brakes bolt into an A-body, which means they also bolt into a Fiero. The A-body HD units add 13# per side unsprung weight over the Beretta brakes (which themselves are a few pounds heavier than stock), so the larger U-Van knuckles and brakes will probably add more than 20# of unsprung weight per side over stock.
The lower ball joint and the tie rod end are bigger on the mini van. The lower BJ looks like it can use the same 3 mounting bolts as the fiero, however, and I'm thinkin you can just thread on the correct tie rod end.
Jinxmutt wrote:The lower ball joint and the tie rod end are bigger on the mini van. The lower BJ looks like it can use the same 3 mounting bolts as the fiero, however, and I'm thinkin you can just thread on the correct tie rod end.
A Lumina Outer tierod end will infact screw onto a Fiero inner tierod end. I've used Lumina Inners on the rear of a Fiero in the past. It's the same tread pitch / diameter.
So if you're going to convert to early cradle to do make this swap, you'll need to do a few things:
-Aluminum or urethane cradle mounts
-UHMW or urethane control arm bushings
-MATCHING FRONT BRAKES
I ran Beretta brakes front with the A-body HD units rear with the stock proportioning and under hard braking the rears would lock up first. This is a dangerous condition that can VERY EASILY cause the car to spin. I intercepted a couple of incipient spins, but that was on Deal's Gap when I was fully warmed up and ON MY F#@$ING GAME. More pucker factor than anything else I've done in a Fiero except the time I flipped one. A sudden emergency situation in daily driving could VERY easily catch the driver off guard.
If you are going to do this, upgrade the hell out of the front brakes. You're smart enough to figure out the relative pressure/torque relationships.
I'll have to do some figuring. I have the Lebaron 11.25 up front and the trans sport is an 11" rotor as mentioned above. I'm not sure of the caliper piston in these, so I'll have to measure that. I already have my axles and I worked on doing my machine work this evening. Hopefully I can get the uprights disassembled and into the blaster tomorrow. Maybe we can section this stuff out of the 88 hub thread??
