Compared to my DD, a 93 Honda Accord, the Fiero dives much more severely under braking. To me it seems excessive. Both cars have stock suspension. The Fiero has Sensatrac dampers.
What could cause this? Or besides stiffer springs and dampers, is there any way to reduce it?
comparing your 93 Honda to a pre-88 Fiero is a tough comparison. I have read that the brake-dive issue was a design problem, and not easily fixed, but the 88 is not so bad...perhaps some more exotic shocks would help.
Originally posted by olejoedad: How old are the shocks?
yes... because old shocks/struts will affect braking. Even more so w/ lowered cars because many have damage shocks and/or struts. Damage on low cars can happen very fast.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
On most older cars, the only thing responsible for brake drive is the springs & shocks. Newer cars typically employ anti-dive techniques - which is a function of the relationship of the front control arms - that cause the actual control arms to resist dive. I believe Mercedes pioneered this on passenger cars in the late '80s, so I think it's unlikely the Fiero has any of that technology - you're going to be relying entirely on springs & shocks. FWIW, my '87 on Koni Specials set to the hardest setting and slightly cut front springs exhibits no dive of which to speak, and I've got a fair amount of brake to play with (C6 brakes). If yours is worse than your Honda's, I would assume you've got something not working properly. "Stiffly sprung" is not a value I'd have attributed to my '94 Accord.
[This message has been edited by thesameguy (edited 06-29-2015).]
That's interesting. I wonder if the Accord has such technology? It does employ a radius arm in addition to the control arm. For a pedestrian vehicle, the setup and geometry is actually quite good (double wishbones).
But yeah its definitely a comfort oriented suspension. Maybe I should change my shocks and see how that does.
The dive you are experiencing is partially due to the rear suspension lifting the rear of the car as well; front suspension geometry on the rear doesn't work all that well.
Anti dive geometry has been around and used in most production cars since the 60's , maybe earlier I don't really know .But basically the upper control arm when viewed from the side with the wheel removed will have a tilt to it at the inboard mounting points .If you drew a line through the upper arm mounting bushings , you would find that the line slopes upward to the front of the car .Generally the shallower the angle the less anti dive .84 - 87 fieros do have anti dive , but it was designed around 13" wheels and tires , low power and fairly light weight .Then later models got the v6 , bigger wheels , heavier body and more options and the anti dive was not enough for a lot of people .But higher spring rates and better shocks will cure most of that .Comfortable ride shocks will make it worse for sure .