Thoughts on upcoming suspension engineering:
Spherical bearing sleeves for Fiero control arms
http://phpbb.realfierotech.com/viewtopi ... 81#p149781
Rod End considerations from New Hampshire Ball Bearing
I have most of the design for the spherical bearing sleeves completed. One sleeve design will be usable for '84-'87 RCA's & '84-'88 FLCA's.
I need to dig my sketch out of storage so that I can build the model in OnShape.
I had previously discussed with NHBB about their spherical bearings with integral seals.
However, based on a friend of my dad's success with Rod End Supply XM rod ends with teflon liners lasting over 10 years without seals on the rear of his Mini, I will look into the spherical bearing version of those. The dimensions will be similar, of course.
I will still use basic shaft seals, since the '84-'87 rear and '88 front both have coaxial pivots that will only rotate the spherical bearing around its axis.
Once I figure out my rod end selection and fitment, I can have the first dozen produced for use on The Mule and the Storm Trooper.
http://phpbb.realfierotech.com/viewtopi ... 34#p151034
Motorcycle caliper piston dust boots
Since there don't seem to be any motorcycle caliper piston dust seals in the size range I need, I might be able to find something in the realm of an old wheel cylinder dust boot. I ran across a post on an off-road fabrication forum in which someone used one for a rod end boot. That's not exactly my application, but it may be workable.
This need applies to the FLCA of the '84-'87 cars only, since those pivots are not coaxial and will result in off-axis movement of the spherical bearing, thus requiring more flexible seals
OE through bolt ball joints
http://phpbb.realfierotech.com/viewtopi ... 46#p153146
SPC aftermarket through bolt ball joint
http://phpbb.realfierotech.com/viewtopi ... 46#p152246
Specs of Lemforder Mercedes ball joint
http://phpbb.realfierotech.com/viewtopi ... 04#p149904
The Dark Side of Will wrote:
The shell diameter of the Lemforder ball joint mics out at 1.5764 (40mm) and the length is 1.8893 (48mm).
Lemforder through bolt ball joint specs from BMW's
The Dark Side of Will wrote:Moused through all 596 pages of the A-B volume of the Lemforder catalog (Alfa, Audi, BMW and 1 page of Buick China)
Picked out the following "through bolt ball joints":
45.2mm OD, 56.7mm long (12mm ID)
33 32 1 138 722
33 32 1 140 345
33 32 6 775 551
The Mercedes ball joint has an unusually small OD for its 14mm ID, which makes it a good candidate for retro-fitting into rubber bushing applicatons... it's just not quite small enough to use in the Fiero control arms
The BMW ball joint called out above has a 12mm ID, but is not quite 1/4" larger on the OD. I guess I'll still stick with the Mercedes unit when I build my own control arms.
Brake package specifications
http://phpbb.realfierotech.com/viewtopi ... 72#p149972
Wilwood parking brake rotor hat specs
http://phpbb.realfierotech.com/viewtopi ... 69#p150169
Specifics of E30 parking brake drum dimensions
Rotors & Calipers:
The Dark Side of Will wrote:The inside depth of the '88 E30 rotor is 2.065".
The depth of the parking brake friction surface from the inner edge is 1.195".
I've been evaluating how to build a cost-effective Wilwood brake package for The Mule, and ultimately other Fieros.
The Ultralite 32 Curved Vane rotor at 12.19" x 1.25" with 8 x 7.62" Rotor Bolt Circle (RBC) costs $81 from Wilwood, so it's pretty economical as high performance consumables go.
The DynaPro Dust Boot caliper works with that rotor, is intended for street applications, and thus has dust boots, but does not have staggered pistons and is not listed for 1.25" thick rotors.
Wilwood builds dust booted calipers with piston diameters of 1.12, 1.25, 1.38 & 1.62", so they should be able to build me DynaPro dust boot calipers with staggered pistons. Building some thick enough for 1.25" rotors is just a matter of putting enough spacers between the caliper halves.
Hats & Parking brake:
Also, there are a limited number of rotor hats for the 8 x 7.62 RBC. The most notable of which are quoted above... using either the BMW E30 or Subaru drum in hat parking brakes. Those are shown with 8x7.78 RBC, but Wilwood should be able to make a pair with the 8x7.62" RBC. They should end up around 5.7# each in cast iron, but if Wilwood will make mine in aluminum, they might be cheaper and save another 5-6# of unsprung weight across the pair.
I originally wanted to use the GM 7.48" drum-in-hat p-brake from a Corvette, but that obviously won't work with a 7.62" RBC.
I have some basic measurements of the E30 hat above, and it looks too deep to use with the 42mm flange offset common across the the Fiero (5x100), A-body (5x115) and Corvette (5x4.75) bearing hubs. I'll investigate the Subaru system. I may have to have even more custom rear hats made in order to package within the available depth. I would also get these made with both 5x115 and 5x4.75" bolt circles to tide me over until I upgrade to the Corvette wheel bearing in the future.
Wilwood has a "Pro-Street" multi-pattern front hat in aluminum that looks useful. I probably have to have a set made with a custom offset, though.
Cheap production package
An alternative system I spec'd used LS1 F-body front rotors and calipers all around. Those rotors are shared with the 2nd generation W-bodies. Since the F-bodies used 5x4.75 and the W-bodies used 5x115, the rotors have an intermediate bolt circle with holes large enough to be used with both wheel patterns. Thus I could use them on the front with 5x4.75" pattern in my Street Dreams hubs, as well as on the rear with my 5x115 hubs under the bolt circle adapters. This system would not use a parking brake at all, and I'd just hope I could get the car through inspection without it. The rotors are 12" x 1.25".
The cheap system would cost $750 and weigh 116.4 lbs, not including caliper adapter brackets.
The Wilwood system would cost $1900 using catalog prices and weigh 76 lbs, not including caliper adapter brackets, but also not including the parking brake shoes and mechanism.
I spec'd both systems with Porterfield R4-S pads.
Shipping costs were excluded from overall price.
So the Wilwood system would allow me to save over 40# of unsprung weight, at an incremental cost of $1150. The figure of merit is $28.44 per pound of weight saved.
Now I need to go spec my clutch and other weight saving measures. The problem with trying to do that level of analysis with the clutch is that I need to make the flywheel, so I don't yet know how much it weighs.