Cascade Crew

[ore89iroc]

I've been looking around the web for the past few weeks for ideas on who's products are the 'best' for rear suspension components.

I'll be rebuilding the back end of my IROC this spring (not including the gears...MUCH later down the road) and it seems Spohn is a very good choice for SFC, Panhard, etc.

Any of you have Spohn stuff? How would you rate the service/products?

[Dewey316]

Steve is great to deal with.

i am one of the very select few people, that have broken a spohn part but i would recomend his parts. i do however suggest not to get adjustable poly/poly LCA's. if you get non-ajustables poly/poly is fine. and infact the added rear roll stiffness from the bushing bind, can in some ways help the feel of our cars. my suggestion as always, is the poly/spherical combo arms. although, myself for LCA's the best design IMHO that you can buy off the shelf is from Global-West. Spohns torque arm is very good, and moving the mount to the x-member is a nice plus. panhards are panhards, no real design diffrence in them, no wierd binding forces, ect ot cause them to fail, like you can get in LCA's.

also, if you are looking for more hardcore parts, talk to CheezX, i am having him build me a set of LCA's, but the are going to be Chromoly rod-ended arms. he has a few other suspension parts, you might talk to him about. and if you come to the dyno, i promise you can see some suprises in a box he bringing with him.

as for other parts, like springs/shocks/swaybars, ect. we will need more info from you on how you plan to use the car, to help you pick out the proper parts there. i don't know you budget, or how much you plan to do, but all the info you will give us, we can help you get a pretty solid combo. we have several people in here that are seriouse corner-carvers and have run pretty serious suspension setups.

[ore89iroc]

Breakdown of parts:

(Global West):
LCA-Bearing on frame side, poly on rear end side-Part# TBC-11
Rear anti-squat brackets - Is this better than Spohn's relo bracket's, quite a difference in design...

(Spohn):
Lower Control Arm Relocation Brackets (or go with Global West)
LCA Mounting Hardware Kit
Panhard Bar - Adjustable Spherical Rod Ended [or should I go with poly non-adj. here too]
Panhard Bar Mounting Hardware Kit
Torque Arm Rear Mounting Hardware Kit
Adjustable Torque Arm - 700R4/T-5 Trans.
Polyurethane Transmission Mount - GM
Sub-Frame Connectors

Other parts:
Aluminum vs. Composite Drive Shaft - Is composite worth the extra ~$500?
Driveshaft Loop - Bolt In - Is it needed since the car won't be a draggster?
Rear sway bar - is it needed? Other than bushings, the rear sway is larger on IROC's than 'normal' Camaro's, correct?
Springs - I already put the Eibach Pro Kit in
Shocks - Will get Bilstein Sports all around later this summer, the previous owner put some decent shocks/struts in, but don't know how long ago.

I'm not looking to make this a drag strip car, 99% of the time it will remain on the street. I want it to kiss the road (as close to a vett as I can get). My budget is limited to reason but I bought the 'roc was because I could afford to max it out and all my coin didn't go into the initial purchase...

I'm sure I'll have many questions at the dyno, possibly enought to be annoying, but man, this sh*t is fun. Ever since I bought the car, I've been plotting!

[Dewey316]

Don't worry, suspension is what gets a few of us really going, cheezx, myself, alloy, schultzy, and a couple other will talk about it for hours on end

your heading the right direction.

hold of on brackets until the dyno gathering

ok, the rest of it i am going to try to break down, much easier in person to deal with THAT much suspension parts. remeber everything has to work together.

LCA's -- Doesn't really matter, with 1 spherical bearing, you eleminate the bind factor. so adjustable or not, you should not releive thread tension due ot bind. that is what cause my LCA's to break. both GW, and spohn have a good design for their combo arms. i like the fact that global west uses a pressed bearing, instead of a threaded adaptor. but on an ajustable arm you have threads somewhere. so that point is mute if you are comparing adj. to adj. if your car has never been in a wreck, it is doubtfull you would adjust the LCA's to anything other than factory setting anyway, so my theory here is that go with the stonger design. which is non-ajustable. but i like having one bearing, for the no-bind design. that is what puts GW's arms at the top of my list.

LCA Hardware--Probably not needed. if you want to replace it for peace of mind, go for it. i am still using my stock bolts.

Panhard, gets interesting again. you will want adjustable. bushings is where you have to make the choice. the thing about the panhard bar, is its movement is linear. there is no twisting forces, or lateral forces involved. so bind is not of concern here. a poly/poly bar will be fine. BUT (there is always a but). the perfmance gains form the panhard come from the 1) lack of defleciton 2) centering the rear to the body correctly because of #1 spherical bearings will give you the MOST performace. as although there is alot less than in a rubber bushing, a poly bushing still deflects. #2 is done from adjusting it correctly, it speaks for itself.

Torque Arm -- Spohn is a good way to go. some people do not like his mount very much, and think it is the weak point, but i have yet to see one fail, and several people who i really trust when it comes to suspension run his arm. most of the poeple who complain are 4thgen owners. you will want a bearing here, as the torque arm bushing can be put in bind (notice the key to suspension here is lack of bind )

Poly trans mount-- big thumbs up there, i have the Energy Suspension mount.

SubFrames---This should be done to ALL thirdgens

Driveshaft--Well rotating mass is always wanted to be reduced, a carbon shaft IMHO is not worth the pricetag. you can usualy get a used LS1 shaft for dirt cheap. you might look into that route.

Driveshaft Saftey Loop -- If you get the spohn TA, get the option for the saftey built in with the TA.

Sway Bars -- I would suggest poly sway bar mounts for sure, as for size, the WS6 cars had the largest, then the IROC's, followed by the rest, which varies from car to car. the IROC has 34mm/23mm bars, the WS6 has 36mm/24mm this is a subject to talk more in depth with us at the gathering, there are alot of variables, include how you drive that go into sway bars.

Did i cover that well enough for now?

[ore89iroc]

That'll work until the dyno! Thanks man!

[sllt1776]

i have spohn LCA's non-adjustable poly/poly. and an adjustable panhard poly/poly. they are great peices......even though they are RED.

[Schultzy89GTA]

[ore89iroc]

yes, the blue brigade has struck again!

[Dewey316]

[TecherB]

[Midnight Sun]

Hmm...


This post is really really informative I appreciate it.


I plan on going through and sprucing up my suspension... But not doing a complete rebuild, what are some suspension pieces that are a good starter (Aside from SFC)

Oh... and does anyone here use a wonderbar?

[Mangus]

I just got my TA from the tranny shop (5th slid down the shaft. Again). I asked the guy working on it to see if he could find out where some of my driveline slop was coming from. He took it for a spin and said the only thing he could think of that matched the "Feel" was the tranny twisting up and down. Looks like I need to look into some better bushings and perhaps an aftermarket torque arm.

I've got Spohn's NA LCA's and NA Panhard. So far so good. Maybe I should invent in the torque arm too?

I also am in dire need of SFC's. Anyone suggest whose fit best? I'm looking for simple installation (i.e. I don't want to have to mess with the exhaust/cat too mcuh to get them in).

[sllt1776]

my car has a wonderbar. i would suggest getting one especially before strain and stress cracks the front subframe near the steering box. it's only a $50 or less peice depending where you get it. i also have the jegster subframe connectors. they helped alot. probably not as good a spohn and the like but they were easy to install.

[Dewey316]

A wonderbar is a good peice to add, if your didn't come with one stock. if you do have one, it isn't worth going aftermarket.

Mangus -- if the tranny has movement that you can feel through the shifter, i would suggest a good poly mount. getting the torque arm off the housing is a nice upgrade. Spohn and BMR make the only ones that do that. and the BMR peice you have to weld in a cross-member and it is much shorter than stock (not a bad thing for drag racing).

For SFC's Spohns are very nice, and a great design. they have their shortcomings, but do their job well. the are weld ins, so it isn't a 'easy' install. but it did cost under $200 to get mine installed. the Alston connectors are bolt in, they are good design. they aren't quite as good for cornering as the spohns, since they strickly tie the front and rear subs together, they don't have the long peice running down the rocker panel. if you do go with the alstons, i would run to a muffler shop, and have them do a quick weld job. it shouldn't cost more than $50-$60.