I really wouldn't worry about it.

quote Originally posted by perkidelic: I have a question about the front suspension for you: What are the "technical difficulties" in the geometry. I have a spare front suspension system that I planned to study, but just figured if someone already knows the numbers it would save me the trouble of setting up something to measure it. perk [This message has been edited by perkidelic (edited 11-13-2003).]

Wow, I printed the "Porsche-ish" potential thread on April 14th and just read it again for the first time today. I have made significant progress since then - on the design. I estimate it will be at least four to six months before I can begin a full-size mock-up though.

That's where this project came from. It lets me use some of the good ideas that I came across, but which weren't right for the race car, and enjoy a Fiero again much sooner. I think I will have a lot of fun in this car next summer. It will also help me immensely with the race car project.

quote Originall posted by Howard_Sacks: I really wouldn't worry about it.

I don't know what you meant by that but I can assure you that I will "worry about it".

Howard you suggested that I go to a full tube chassis in that thread. While I still prefer to base my "ultimate creation" off the factory "space frame" it is nearly as far as one can go without doing a full tube frame. There will be tubes everywhere, but somehow it will still say "I'm a Fiero" from inside the "cockpit".

perk

Hey Will, are you still out there?! I did some scrounging around today and have a question. I was checking on C5 knuckles for my race car and decided to check the hub/bearing assemblies while I was there.

They are about $700 each! Granted this was brand new at a retail Chevy parts dealer, but it isn't likely to get much better than this. Of course, a guy could dig up a used set on E-bay or at a recycling yard but that leaves things up to chance. My guess is it's the ABS stuff on it that drives the price so high.

It's hard to tell from the pics but it seems that the C5 knuckles have a three-bolt pattern for the hub. If that is correct, do you think a 4wd S10 hub/bearing assembly would bolt to the w-body knuckle? This would give the average Joe a more affordable solution, and possibly still afford the diehard racer the opportunity to have the best (C5).

I priced a new Timken hub assembly for a 4wd (non ABS) at Autozone and it was only $79. What do you think? The S10 hub has a 3-bolt flange. Do you think the bearing is up to the task?

For hwat it's worth the C5 knuckle is pretty reasonable at $160 retail.

perk

Dude, lots of information on this post!!! I just wanted to say that I have Suspension Techniques lowering springs and KYB struts and I love the ride. Sporty, but not jarring at all. I wish I could say something about damping rates or quote some sweet numbers, but I'd be fooling myself, I don't know a thing about that!

The S10 uses a larger mounting circle than the C5/GTP/P6K parts.
I didn't check the price of C5 bearings, but CarQuest had one in stock, so I didn't think they were outrageously expensive. AWD Astro van bearings were pushing $400 and they didn't have any of those in stock.

------------------
'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

[This message has been edited by Will (edited 11-18-2003).]

Depends who you talk to.

I'll try to elaborate more later.

quote Originally posted by Will: Which is more desireable? Excellent camber characteristics or very low roll center?

quote Originally posted by Howard_Sacks: Depends who you talk to. I'll try to elaborate more later.

I know it depends on who I ask. That's why I haven't figured it out yet.

------------------
'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

I was going to price an aftermarket C5 bearing today but didn't have time. Maybe tomorrow.

I asked some diehard handling/racer guys about their thoughts on camber curve vs. roll center, just out of curiousity. Myabe they'll say something that helps.

perk

.. . .

tough question Will. How bout both are important? So is scrub.

still thinking this one through. . . .

[This message has been edited by Howard_Sacks (edited 11-20-2003).]

I priced the C5 bearing through GM Parts Direct:

$ 347.46 + 69.49 (s&h) = $ 416.95 each

Much better than seven hundred, but still not exactly cheap.

I have been working with the guys I mentioned on the front suspension geometry. Today I am gonna pull some measurements from a complete front setup I have off one of my cars. After we toss them around for a while, I'll share the results to see if you guys like it.

So far, the common consensus there seems to agree with Howard about having a more consistent roll center. The factory specs someone gave me puts the front roll center of a Fiero at 60mm and the rear at 27mm. That's for a stock 84 with 185/80r13's.

perk

Perk, looks like these guys are building your car. well they're using alot of the same parts kinda.. http://factoryfive.com/table/ffrkits/GTM/GTMkit.html

That factory five car is cool.

quote Originally posted by Howard_Sacks:You're going to need to get some measurements for uprights and know what offset wheels you're using to start calculating roll centers Perk.

I have 'em Howard. I am gonna put 'em in the diagram, and see what some of the numbers look like, just didn't get to it yet.

Rims = 17x8.5" (65mm offset) (C5 wheels)
Tires = 225/45R17

I'm gonna move up to something bigger (rim diameter) than these later, but I'll try to keep the same overall dimensions and offset.

As for the knuckles, this is for my "mild" project so I am planning on using the factory height (84-87) knuckles. Actually, I plan to buy Will's aluminum design from Street Dreams. Just trying to see if it is possible to change the arms and/or crossmember (pick up points) to get an improvement in the geometry.

quote Originally posted by Howard_Sacks:Your measurements might be the kick in the butt I need to get up and write some simple software to calculate basic suspension geometries so I don't have to pirate someone elses.

I think the one I am gonna buy is around three hundred.

perk

I was looking at the front suspension setup again today and noticed how deep the rotors are. In my diagram I didn't illustrate them correctly. This is more accurate:

With a flatter bearing assembly it would be possible to push the knuckle out much farther and use longer arms. Wasn't that one of the 88's improvements?

perk

Yes. With relatively little cutting and welding an '88 front suspension can be grafter into an early chassis. Been there, done that.
So the '88 inner pivots are in much the same location as the early inner pivots (except they don't have FQ@#$#@ PRO-DIVE). Look at an '88 knuckle and you'll see that the ball joints are pushed outboard noticeably. This is the '88's widely known reduction of scrub radius. The '88's ALSO have a slightly larger hub-to-hub distance than the early cars, which allows even a little more control arm length.

I still thinkin on it. Classwork's been getting in the way unfortunately. Just finished a Thermo exam on the otto cycle :-/

Haven't heard of tuck. You mean tuck-in I guess. Yeah.

edited as to not confuse people. . .

[This message has been edited by Howard_Sacks (edited 11-28-2003).]

quote Originally posted by Howard_Sacks: Thermo exam on the otto cycle :-/

Suck, squeeze, bang, blow. Everything else is easily derivable.

Well, I was thinking about roll center movement near ground level, but inboard beyond the track of the inner tire. This would cause cornering G to load both tires, not load the outside and unload the inside... but I have no idea what a driver would feel in a suspension that did that.

That's probably all academic as I think that whatever feel it does provide, it wouldn't provide a consistent feel, which is what the driver really needs to push hard.

Another thing I've been thinking about is anti-dive and squat during cornering. They increase the effective spring rate in proportion to acceleration or braking forces, which should balance the shift in dynamic weight distribution accompanying the aforementioned acceleration and braking forces... but then you end up with one end of the car heavy and stiff, but the the tires no longer proportionally distributed... but that's the case no matter what causes weight transfer.

I need hydraulic upper control arms to actively control my camber. A Mercedes prototype did this and could pull 1.26 G's on the skid pad on street tires. Would love to know what it's like to drive with dynamic suspension geometry, though.

------------------
'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

Just a thought, but have you ever considered gathering as much hard data on how the manufacturers and racers set up their vehicles and comparing it, Will? Like BMW's data compared to a Z06, compared to a 911T, etc. I know it would be a serious task but you are the absolute KING OF RESEARCH

I wish I had your "gift" for it cuz it would be interesting to see the real data behind how manufucturers, etc, develop the proprietary brand "feel" they have.

perk

I've been thinking about this comment and a light went off.

Maybe that's what G. Ryan experienced when he tried racing on that suspension and found it less competitive then stock. Even though common sense says a tubular suspension should be lighter, stronger and all around better. There's got to be a reason why it didn't work.

Weight transfering to the outside tire isn't all that bad so long as tire performance doesn't drop off or that the suspension goes into positive camber from roll and poor geometry.

You might just not be able to geometricly load that inside tire with enough force to make up the difference from the loss off the outside.

quote Originally posted by Will: Almost all the designs I've seen have the roll center moving outboard, though, which causes the cornering G to try to unload the tires. Interestingly, the Ryane/Held Slalom setup has a roll center that moves inboard.

Well... considering that the lateral grip available from a tire isn't proportional to the normal force, but closer to proportional to the square root of the normal force, then the most grip the vehicle can achieve would be with all four tires loaded equally. The closer you can come to that the better the car will grip. That's why softening the suspension can give you a little better grip, because it reduces the weight transferred off the inside tire.

------------------
'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

quote Originally posted by Will: Well... considering that the lateral grip available from a tire isn't proportional to the normal force, but closer to proportional to the square root of the normal force, then the most grip the vehicle can achieve would be with all four tires loaded equally. The closer you can come to that the better the car will grip. That's why softening the suspension can give you a little better grip, because it reduces the weight transferred off the inside tire.

My thoughts exactly. I'm glad you said this when you did, I was just about to dig out my books and make sure I wasn't getting mixed up!

For the record, I'm all for the confidence inspiring suspension setup...all the theoretical handling in the world isn't going to mean squat if the driver isn't on the same page as the car. We can design the car for a perfect driver, but I don't think any of us will find a perfect driver to try it out!

Bryce
88 GT

Might still want to. I'm putting together a PM for Will I'll cc you on.

quote Originally posted by Nashco: My thoughts exactly. I'm glad you said this when you did, I was just about to dig out my books and make sure I wasn't getting mixed up!

The name of the chassis book I mentioned but couldn't recall the name of was The Automotive Chassis.
http://www.sae.org/servlets/productDetail?PROD_CD=R-300&PROD_TYP=BOOK&COMMON_SUCCESS=TRUE

Got it, but you asked the wrong question. :-P

Roll center control is more important.

"You have to have at least one firm base on which to begin creating your suspension design, and nothing I have been involved with over some years has shaken my conviction that the best, and possibly the only, reliable starting point is the Roll Centre. You have to cling on to something." Guess who said that . ... wasn't Carroll btw.

Roll center movement in both lateral and vertical directions is bad. The number quoted to me by a formula ford chassis designer to keep sideways motion in roll is under .2 inches per degree of roll. F1 cars keep it under .020 for the total wheel travel.

In addition, while cornering, the Center of Gravity of the vehicle moves toward the outside. The CG is different than static weight and it moves. If you have the roll center move inboard during roll, you will increase the distance between it and the CG of the vehicle by an abnormal amount. Doing so is bad because as the distance increases, so does the roll moment. The greater the roll moment, the greater the force the CG will exert on the tires. If the roll center moves with the CG, the moment will stay constant and the tires will be loaded evenly through the corner.

Another VERY important issue with RCs and suspension geometry is that front and rear roll centers need to match. The line between the front and rear roll centers or the roll axis should be parallel with the mass centroid axis or the line that would be drawn if each section of the vehicle had it's individual cg taken and had a dot graphed. By keeping the lines parallel or at least keeping the distance between the cgs and rcs or roll moments equal both ends of the car will have lateral load transfer in a stable manner. If the vehicle has different roll moments, the end that has the larger moment's traction will suffer. This will confuse your driver as the car will push, then hook up if the driver takes no correction on corner entry or oversteer and then flop ends the other way.

Camber curves just need to increase slowly with roll angle as to keep the tire's contact pact maximized. Static camber can be easily changed so that peak cornering force can be obtained, but roll centers cannot be easily changed at the track so the driver can approach the limits with confidence.

This is not to say that camber curves are not important. By getting camber curves dead on, more traction can be had while "setting" the car into the corner. Also if less static camber can be used on the car, by getting camber curves right and not needing to dial in additional camber, better traction can be had in both acceleration and braking.

I guess what's to be learned is that you can't just make a front suspension package without touching the rear if you're modifying roll centers.

Hope that helps. I don't think anything I've written is gospel, so if ya think I'm wrong call me on it and make me learn! Still working on the ROI issue. You guys aren't looking at the right graphs ;-) and I was less then clear.

quote Originally posted by Will: Which is more desireable? Excellent camber characteristics or very low roll center?

[This message has been edited by Howard_Sacks (edited 11-28-2003).]

quote Originally posted by Howard_Sacks: Another VERY important issue with RCs and suspension geometry is that front and rear roll centers need to match. The line between the front and rear roll centers or the roll axis should be parallel with the mass centroid axis or the line that would be drawn if each section of the vehicle had it's individual cg taken and had a dot graphed. By keeping the lines parallel or at least keeping the distance between the cgs and rcs or roll moments equal both ends of the car will have lateral load transfer in a stable manner. If the vehicle has different roll moments, the end that has the larger moment's traction will suffer. This will confuse your driver as the car will push, then hook up if the driver takes no correction on corner entry or oversteer and then flop ends the other way.

I've been thinking about that for a while, but I didn't have the terminology to express it. "Centroid axis"

That's actually a Carroll Term from "Tune."

quote Originally posted by Will: I've been thinking about that for a while, but I didn't have the terminology to express it. "Centroid axis"

Ended up getting a 95/100 on the exam even though I couldn't stop thinking about roll center moments while studying. Over 75 is an A. Would have gotten a 100 but the professor was wrong. Lame.

quote Suck, squeeze, bang, blow. Everything else is easily derivable.

I was referring to the concept that the roll axis should be parallel to the "centroid axis" for matching roll moments front and rear.

Good job on the exam.

I'll hold off on SLA suspension replacements for a while... If Street Dreams ends up making '88 knuckles, I could use those to stretch the control arms in the early suspension, while retaining stock pickup points on the tub.

First things first... got to get rid of pro-dive and pro-squat on the early suspension.
I will be machining wedge shaped blocks to go between chassis and X-member in early front suspension to rotate the whole thing forward and raise the side-view instant center until is at least doesn't have pro-dive. May even work in a small amount of anti-dive.

I have similar ideas about the rear suspension. Eccentric and angle milled cradle bushings can rotate the cradle to the rear to reduce or eliminate pro-squat. However, due to the critical top-side tolerances with the N* (and other) engine swaps, they will have to be set up to rotate the cradle around an axis at the top of the engine compartment.

------------------
'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

We were actually talking about that this past week. It's going to be tough to get geometry to work for you while being bound to stock tub mounts.

The rear, pretty much is limitless as for as suspension design goes because you can throw away the stock cradle and go custom so easily.

quote I'll hold off on SLA suspension replacements for a while... If Street Dreams ends up making '88 knuckles, I could use those to stretch the control arms in the early suspension, while retaining stock pickup points on the tub.

We used pretty much did that on the 2002 car except by design.

quote Eccentric and angle milled cradle bushings can rotate the cradle to the rear to reduce or eliminate pro-squat.

I need to get me a mini-lathe so I can start talking about doing crazy stuff like angled bushings. Don't go too wild with the anti-dive. I wouldn't go past 10%. I guess if machine time is free for you, you could make a couple sets and see which you like best.

I've got a question for you now,

Why aren't you working with an 88 rear? N* issues?

quote Originally posted by Howard_Sacks: Why aren't you working with an 88 rear? N* issues?

I know I don't want too much anti-dive because it makes front spring rate effectively dependent on braking force... however that could be used to help settle the car on corner entry...

I am conceptually working on the '88 rear. The biggest thing for me right now is that there are no ready made hub carriers for the '88 which will accept larger bearings. Using 5x100 bearings is a dead end. They just don't last in a heavily campaigned car.

I know what I want a custom '88 hub carrier to look like, but it's not that high a priority right now, because my car has early rear suspension
Anyway, I'd use an aluminum plate for the bearing to mount, reinforced square tubing for the strut clamp, and I'd have the lateral link and trailing arm pivots bolt on separately. When you lower an '88 with springs, you get further up on the camber curve and reduce the camber gain per inch of suspension deflection. By lowering the pivots the same amount you lower the chassis, you stay in the same place on the factory camber curve... or you can lower the pivots more than you lower the chassis and have a little more camber gain. And if the trailing arm pivot is adjustable separately from the lateral link pivots, then you can have independent adjustments for anti-squat and camber...

Going to the strip? back off on the camber a notch, go a notch more aggressive with the anti-squat, and back off the compression on your D/A Konis.
Going to the track? go a notch more aggressive on the camber, back off a notch on the anti-squat, and set your crank the aforementioned D/A Konis full stiff.
But that's for a little further down the road.
I want to do all my experiments with the early suspension before I convert my car to '88 rear. I also help more Fiero owners by taking the early suspension as far as it can go than I would if I dealt exclusively with the '88 suspension.

Edited because we all have D/A Konis, right?

------------------
'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

[This message has been edited by Will (edited 12-02-2003).]

quote Originally posted by Will: First things first... got to get rid of pro-dive and pro-squat on the early suspension. I will be machining wedge shaped blocks to go between chassis and X-member in early front suspension to rotate the whole thing forward and raise the side-view instant center until is at least doesn't have pro-dive. May even work in a small amount of anti-dive.

Sounds like fun! Will there be sufficient adjustment to get enough castor?

quote Originally posted by Will: I have similar ideas about the rear suspension. Eccentric and angle milled cradle bushings can rotate the cradle to the rear to reduce or eliminate pro-squat. However, due to the critical top-side tolerances with the N* (and other) engine swaps, they will have to be set up to rotate the cradle around an axis at the top of the engine compartment.

How many degrees does it have to rotate? sounds like you would be shortening the wheelbase a bit, or am I picturing the axis point wrong?

I am seriously thinking about just building a new cradle. It's basically just four mounting points, four suspension pickup points, and two lateral link pickup points. The main rails would be simple to do in 2x3", with round tube crossmembers.

No aluminum bushing needed, because it would be a solid mount deal from the beginning. The suspension pickup points would be optimized, and it should be a true bolt-in part.

quote Originally posted by Will: I'll hold off on SLA suspension replacements for a while... If Street Dreams ends up making '88 knuckles, I could use those to stretch the control arms in the early suspension, while retaining stock pickup points on the tub.

I forgot to get into this after seeing the pic of the new knuckle. It looks like there is enough room on the "face" of that knuckle to machine it for a flatter bearing, instead of the spindle. Basically just a hole machined in to accept the bearings flange, and the holes for the mounting bolts. If there is a shallow bearing out there you could get much longer arms.

That's what I am personally looking into. We haven't had time to start on the geometry yet, but hopefully soon. I also need to start looking for bearings. I did look at the 4wd S10 bearing. It is about 47mm from the outside (of the hub) to the mounting surface. I haven't taken the time to get an accurate measurement of the stock 84-87 Fiero setup yet but an eyeball (while holding a caliper and a tape measure over it) gives me something like 3.5". The S10 bearing would allow the arms to be over an inch and a half longer.

perk

[This message has been edited by perkidelic (edited 12-02-2003).]

[This message has been edited by perkidelic (edited 12-02-2003).]

Wow, you like to do things the hard way...

There are a lot of easier things to do that will give a very large fraction of the improvement that 100% custom hardware will give.

Yes, the cradle bushigs will decrease the wheel base slightly... maybe 1/2" or so... and they're a lot cheaper than a cutom fabbed cradle.

I'll be using the anti-dive blocks with 2" lowering knuckles, so I'll end up with a 1" drop from 2" knuckles.

Once Jeff at Street Dreams perfects making the new early knuckles, they might tackle '88 knuckles, in which case a good base would be available to build a front suspension replacement for the early cars. I'll see to it that alternate bearings fit. I think a C5 bearing would be a better choice than an S10 bearing.

------------------
'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

quote Originally posted by Will: Anyway, I'd use an aluminum plate for the bearing to mount, reinforced square tubing for the strut clamp, and I'd have the lateral link and trailing arm pivots bolt on separately.

I'll have to go to my storage unit (which won't happen soon as I'm recovering from knee surgery...) to look at the '88 suspension I have stashed there, but I've been thinking that the control arm pivots might not even have to bolt on. There may be room for three mounts and inch apart each on the hub carrier. To change cambe curve, just raise the car up, get the wheel off, pull out the lateral link pivot bolt, set the pivots on the new hole and put the bolt back in. Similar procedure for trailing arm.

Once these units are available, it would be possible to build a control arm to adapt them to the early front suspension. This control arm could be set up like the Held bump steer kit, only simpler because of the more convenient hub carrier design, and it would eliminate bumpsteer from the early chassis while simultaneously removing unsprung weight and allowing all manner of larger bearings.

So with the right control arms, '88's and early cars could share hub carriers and aftermarket brake components at both ends if these hub carriers come into existence.

------------------
'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

I think the main thing with the early suspension would be getting everything on the same plane.

I don't think it would be all that hard to modify an early cradle to use 88 arms. I'm also with Perk in thinking it wouldn't be that hard to just make a new cradle.

So if Street Dreams is making 88 style uprights and hubs, those who are ambitious could buy that, make some crome moly links and modify their cradle and be on the right track.

btw Will, I'm going to be putting 500+ftlbs to the ground and using wrinkle walls. What do you think MTBF is going to be on the bearings? I hope you guys have some solution for the 88s out by summer.

Wow, amazing thread guys, It only took me an hour and a half to read everything. I will be very interested in seeing what you come up with.

I would LOVE to upgrade both suspension and brakes - only problem is I have anual safty inspections. This means they check the whole car over and don't take too kindly to custom built things - This being the case a setup made from readily available parts taken from other cars is pretty much a must. A custom Tubelar engine cradle is out - I've looked into this already and was greatly disappointed when I found out just how stingy these people can be. Spacers/adapters to mount brake calipers are also frowned upon greatly here. I hear you guys talking about using Corvette parts & S10 parts and I just hope you can find something that will work.

Another plus if you are able to develope a setup derived from other cars is that parts will be readily available to other people to get the parts and hopefully improve many things for the Fiero world in general.

One thing I have noticed is that in no place does anyone mention anything about air-ride suspension at all. Why is this? I realize the cost may be greater in some aspects, but would it not simplify things in certain aspects for those people who wish a soft comfort ride, as well as a stiff suspension for cornering and what not?

I read in another post a while back about newer cars using a variable ride suspension that even varies pressures to each wheel to improve cornering and handeling. I feel that with the use of a gyro such as those used in model helicopters that much the same could be done - though it would take some research to figure out just how this whole setup works. Should this be the case applying certain pressures to certain wheels should supply the ability to (moderatly) dynamically change loads put on wheels and suspension components, as well as possibly provide the same effects as progressive rate springs?

I am the first to admit that I am completely unexperienced in this area - but am eger to learn. I hope to get one of 2 of these books if available from my local libary over Christmas Vacation - regardless just thought I would throw some ideas out there, as well as some questions, and hope that maybe these questions be answered

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http://dewie.no-ip.com

quote Originally posted by Howard_Sacks: I think the main thing with the early suspension would be getting everything on the same plane. I don't think it would be all that hard to modify an early cradle to use 88 arms. I'm also with Perk in thinking it wouldn't be that hard to just make a new cradle. So if Street Dreams is making 88 style uprights and hubs, those who are ambitious could buy that, make some crome moly links and modify their cradle and be on the right track. btw Will, I'm going to be putting 500+ftlbs to the ground and using wrinkle walls. What do you think MTBF is going to be on the bearings? I hope you guys have some solution for the 88s out by summer.

Well... the primary stumbling block to getting everyone on the same page has been that the early cars and '88's don't use the same stuff. By making them use a lot of the same stuff, things are simplified dramatically.
I think that a control arm is best with the '88 knuckle and early cradle. Using separate links dramatically reduces triangulation against the 500 ftlbs of torque that you'll be putting to the ground. Unless you ALSO add a trailing arm into the mix... but that complicates things (unnecessarily, IMO).

Now fixing the early suspension certainly involves moving a pivot point or two. Need to get rid of the tiny bit of semi-trailing arm behaviour that it has, as well as the pro-squat, but I don't think those two tasks will be very difficult at all.

------------------
'87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
'90 Pontiac 6000 SE AWD: Leaking ABS unit fixed, load levelling rear suspension fixed, still slow

quote Originally posted by Howard_Sacks: I think the main thing with the early suspension would be getting everything on the same plane.

quote Originally posted by Will: Well... the primary stumbling block to getting everyone on the same page...

I thought Howard was talking about getting the pivot points on the same horizontal plane - like what you are going to do with the wedges on the front suspension (?).

I'm gonna have to print this thread to go with the "Mid-engine Drag Racing 101" and "Porsche-ish Potential" collection

perk