nedry

I'm long-term-planning a MAJOR rebuild on a Firebird and, since I'm running behind the power curve on picking up automotive knowledge (I'm usually a very fast learner... this is SO embarrassing... ), I figured I'd better ask the experts for advice.

Question number one
The goal:
Total suspension overhaul for maximum strength-to-weight-ratio possible, using only "off-the-shelf" parts. For the purpose of this question let's assume that no single part is too expensive, but that you're only allowed to bring in a machinist and shop to install parts, not custom-fabricate new ones (except maybe a few small brackets). This question includes such things as strut tower braces and wonderbars as suspension.

The catch:
It's gotta fit on a Firebird with full dual 2-1/4" exhausts, fully emissions-legal, lowered via 1.5" drop spindles front/Jamex springs rear (or the Eibach Sportline kit with a drop of 1.6" front/1.3" rear; please state which of these scenarios you're using). Drivetrain is a 4L60E with a Saginaw 2.56 posi rear axle and an 8" FluiDamper (uncertain about diameter of lockup converter. It's also gotta clear one of the following fuel tanks (again, please state which you're assuming): Fuel Safe SA114 24-gallon fuel cell, GM 10121026 1LE 18.5-gallon tank (did GM produce one of these in plastic for fourth-gens?) or a fourth-gen plastic 15.5-gallon tank. Also, we're looking at somewher between 17x7 and 17x9.5 wheels front and rear. The engine would be a 90* V6 with CPI fuel injection.

Question number two:
The goal:
Maximum braking power, again using only off-the-shelf parts (and again, small parts like brackets are allowed to be custom-made).

Initial options under consideration:
Corvette Z06 or C5 brake retrofit
Corvette C4 brake retrofit
LS1 brake retrofit
1LE brake retrofit

I've been reading the stickies about C5 and 1LE retrofits, and have read the Tech Article about the LS1 add-on, but I'm not sure which option would be best (although I lean toward the C5/Z06 as the newest technology... but I've still got a lot to learn...). My thinking is that a major brake upgrade will help with safety considerations by reducing stopping distance, and a beefed-up suspension would make the car both safer and more durable. (I have a thing for structural strength... in my high-school architecture class, the interior walls on my floorplans were as thick as everybody else's EXTERIOR walls. Plus I'm extremely possessive about my property, if I'm going to bust my butt on tweaking ANYTHING to my preferences, I want that sucker, with proper maintenance, to last for several decades, ideally longer...)

And a general metallurgical question: how much better, if any, is chrome-moly than mild steel?

Any advice would be appreciated, if a long time before being put to the test. It's funny, six hours with the book and for a month thereafter, I could quote detailed maintenance and operation procedures for one of GM's early-'80s locomotives, but for some reason, their smaller-size product line is not being absorbed as fast...

I guess this is just a stage I have to pass through as part of the learning process...

Later.
nedry OUT

[Edited to fix emoticon error]

REVLIMIT

ideal suspension in my eyes:

-Ground control weight jack system
-Advance design front struts
-Koni custom valved rear shocks
-drop spindles
-LCA relocation brackets
-tubular front control arms
-tubular rear control arms
-tubular panhard bar
-eldebrock strut tower bar
-subframe connectors...personally this one brand terminator
looks the best...not super great for ground clearence but a good design for tying the frame together.
-suspension techique sway bars
-ground control camber/caster plates
-spohn wonderbar
-tubular torque arm

As for brakes...I'd go with the C5/Zo6 front and LS1 rear...which is pretty much what I have planned for my car. Cheap, reliable, and easy to get parts for. Also get yourself an adjustible proportioning valve and steel braided brake lines.

The only real advantage of chromoly over steel is that its stronger. So they can make the tubing thinner which will make it lighter and at the same time it will be the same if not alittle stronger then the steel. The only problem though sometimes is that chromoly is so strong and so thin that it can crack. Since if you make something to strong it becomes brittle. But most of the suspension peices wont really crack. Except I heard that tubular chromoly k members do sometimes that and chromoly roll cages.

Dewey316

i pretty much agree, personaly while we are dreaming i would run the adjustable bilstein race shocks out back.

and also, if the car is going to live on anything but super sticky race tires, my gut says that the suspension tech. sway bars, along with the high rate of springs i am sure the ground control kit comes with, it is going to be a little too much, i would go with smaller sway bars (personal pref. though).

also, if you are still using the stock steering box, get a TDS wonderbar, it saves wieght, and does what i needs to do, the spohn is overengineered IMHO, and i also don't like the adjustable thing.

i would stay away from a tubular k-member (until someone makes one more suited for road-racing) for now.

brakes (i can't say right now) but ask me in another month! (trust me here, ask me again about this later )

almost everything there is basicly bolt on, there is no real reason to re-design the wheel. with the right components our suspension is very good.

REVLIMIT

yea thats true the ST sway bars are way to big if your going for handling. But if your going for drifting then its all good. But I'm guessing your not tuning your car for that

nedry

Thanks much for the recommendations. The goal for what I'm hoping to build is a daily-driver/long-distance cruiser, but I want to build this thing to LAST. Engine and drivetrain prescription was written to maximize fuel economy at highway speed, engine involved is a 90* V6. Also, I probably should have mentioned that ground clearance is somewhat of an issue, between the 1.5-1.6" lower, speedbumps, and these nutbars who have to have steep ramps into/out of parking lots... what do they think, everybody drives an SUV?

Tires are BFGoodrich G-Force T/A P245/45R17s. (Hopefully, they have a Z-rated version...)

Eventually, if it turns out to be feasible, I'd like to put in fourth-gen rack-and-pinion steering. (If that doesn't work out, fallback position would be a GTA or IROC steering box.) I think some folks were discussing such a swap here recently...

Thanks again for the advice. I'll start checking into things ASAP.

Later.
nedry OUT

nedry

Will a torque arm for a 700R4 work with a 4L60? Or would a 4L60 require a torque arm design of its own?

Thanks much!
nedry OUT

[EDIT: Did some checkingaround the transmission board and if my understanding's correct, a 4L60's just a 700R4 with a new name and some electronics. Never mind... POst only being left for archival reasons]