: Project: 78 Brougham/Suspension Upgrade



Wheelman322
06-28-06, 08:06 PM
After 4 years of hibernation, I am finally ready to take my Brougham to the next level. As a perfectionist, I would like to do everything correct. I need some recommendation as far as upgrading the suspension (i.e: 9C1 parts, TA steering box, and B body sway bars). I read that I can retain the factory air ride, but upgrade to 9C1 springs and get some decent handling. Any replies will be appreciated.

N0DIH
06-29-06, 12:23 AM
I would recommend 70-81 F Body front bar, fatter (1.25") and shorter lever makes it a more effective bar.

Which T/A steering box do you have? 70-81 or 82-92? The 70-81 has internal stops that might hurt tighter turning. As always, get a WS6 steering box, it is a constant ratio and a 12:1 ratio. I hate variable ratios! But I am stuck with them.... That is why most people thing rack and pinion is so much better, ratios...

The 82-92 box might be better. The 92 WS6 being the best. It will have the best road feel.

Wheelman322
06-29-06, 01:47 AM
Thanks. That's exactly what I wanted to know. Any clue about the springs and shocks?

N0DIH
06-29-06, 02:17 AM
Shocks, Bilstiens. Best period. Not the cheapest... And they replace the rear air shocks, so you have to adapt air bags in the rear springs to the compression.

The factory V4P springs are same RATE as front as the Impala SS. The rear I don't know, but are pretty decent and can handle some decent weight for trailering. Go to the GM dealer, look for the TP and HF springs from a 94 Fleetwood. Those are what mine has. If you want lower, Impala SS springs are just shorter in height in the front, but same rate as the V4P (RPO FE2)

How stiff do you want? 9C1 are stiffer, but may be objectionable. I haven't ridden in one, so I can't say for sure. But it can't be stiffer than my 80 T/A with F41 suspension. That feels like a rock compared to my Cad. But I always thought it needed to be stiffer when I drove it hard. Herb Adams always liked the soft spring/stiff bar setup. Dick Guildstand liked the stiff spring and minimal bars (often no rear bar) and use the engine power to manage over/understeer.

I am running the Gabriel Ultra 9C1 front shocks now and love them. For the $ they do very well, only $28 each locally at Autozone. It really can handle a lot of bumpy roads well far better than any other car I have driven, and these roads here can be bad. My rear shocks are AC/Delco air shocks and they are getting pretty old now and let the rear end hop over bumps. I need to get them out.

I have factory Bilstiens on my 120K mile 99 K2500 Suburban (rare option!) and it still does very well. Bilstiens are often at 85-90% of NEW performance at 200K miles. They are a very good investment.

caddydaddy
06-29-06, 02:25 PM
Thanks for the info! I'm looking into upgrades for my 1979 Deville as well!

N0DIH
06-29-06, 06:06 PM
In the old Real Street Eliminator series Car Craft did, the #1 title on year went to a 500 CID Cadillac Coupe DeVille! He did everything well and ran low 12's.... Even handing and braking was on par with the lighter F and Fox cars it was up against. They gave this guy a lot of respect with the power it had. Anyone got the article?

Follow Herb Adams on the Cheverra (Camaro+Cararra) he did, he had that thing with a 396 BB Chevy running on race tracks at 150+ mph with a modified stock front suspension. Which is what we have under our cars. He was also one of the chief designers of that suspension.... So if he can make it sing, it WILL be good!

Wheelman322
06-30-06, 02:20 AM
NODIH...You are awesome. I can't thank you enough for the info that I probably would have hunted for months for. Thanks again. :thumbsup:

N0DIH
06-30-06, 01:19 PM
I found it from a post on the Impala SS site and some research I got from Dal and put it all together. And there is this 300-400 magazines my wife wants to toss.... And I have this bad habit of remembering that I read something in one of them....