How to fix a nose dive while braking.

[twr]

Have you or do you know someone who has done this or are you compairing a GEN 1/2 to GEN 3. The lack of nose dive while braking for GEN 3's is a result of the SARC system. SARC adjust the shocks automatically to prevent nose dive while braking. SARC for a GEN 2 would take some modifications to work. I know this because I'm currently retrofitting my 94 back to stock strut system from a 97 SARC system.

Actaully it has been done, Kirk did it. The design of the Gen 3 subframe and lower control arms does eliminate some nose dive under braking. Not every Gen 3 had SARC on it.

 

[naval-avi8or]

Actaully it has been done, Kirk did it. The design of the Gen 3 subframe and lower control arms does eliminate some nose dive under braking. Not every Gen 3 had SARC on it.

Well I'll look foward to the improvment once I get my struts back on my car. The Gen 3 suspension just wasn't cutting it don't know if the strus where bad, sensors weren't mounted correct or just to much of a lower suspension. I was just getting to much whell rub over rough roads or with any loading of the car. And 99 SHLO's don't count:laugh_ti: they are just wanna be SHO's

 

[93silverbulletSH0]

I was looking at this earlier today and was wondering what was up with the suspension (third from the bottom). You can tell that it is a gen II, but it doesn't have gen II suspension. I now realize thanks to this thread that it is a gen 3 subframe conversion.
Are there any other benefits to this type of a swap, like reduced weight or improved handling?

 

[K-Dawg]

Yes, that's Kirk's car with the Gen 3 subframe, LCAs, and knuckles. The suspension geometry is better, and you do save some weight. I think Kirk told me the combination of the subframe, control arms, and knuckles saves about 18 pounds. You also have the benefit of using the ZF rack which is better than the Gen 1/2 rack.

 

[SolidState]

except the ZF rack is controlled VIA the ABS, IIRC. Uses the same speed sensory system as the SARC.

Other advantages of the Gen3 setup is the lighter knuckle (unsprung weight) and easily replacable wheel bearings/hubs.

 

[naval-avi8or]

Yes, that's Kirk's car with the Gen 3 subframe, LCAs, and knuckles. The suspension geometry is better, and you do save some weight. I think Kirk told me the combination of the subframe, control arms, and knuckles saves about 18 pounds. You also have the benefit of using the ZF rack which is better than the Gen 1/2 rack.

From my prospective I could have sworn that the GEN 3 subframe was alot heavier. However my scale was me on my back trying to hold the damn thing up and put the bolts in.

I've asked before but got no response but does anyone know if there is a difference in width GEN2 to GEN3 hub to hub. This was one of my first thought was that the GEN3 had just a little wider stance.

 

[1slickRED89]

if you can get the front LCA pivot point to line up with the rear LCA pivot point and the cars center of mass the car will not nose dive. imagine cutting the car in half long-wise and drawing a line from the center of mass and it would cross the rear and front LCA pivots.

I have no idea how you can do that, but that's how race cars are setup. the same idea can go into anti-squat rear suspension. I know because I read it in a book, so it must be true.

 

[K-Dawg]

I also wondered if the front track width was wider on the Gen 3.

It's been a while since I handled a MTX subframe by itself, but the Gen 3 subframe I have seemed pretty light.

Can anybody confirm the ZF rack being controlled by the ABS? I was planning to use one in my car.

 

[naval-avi8or]

Sorta, GEN 3's do not have a VSS so VAPS speed signal is generated by the ABS via wheel speed sensors. Other than that it should work and at most require some pin/connector modification.

 

[K-Dawg]

After some research, it looks like the VAPS signal goes through the SARC module on the Gen 3s. For some reason I was under the impression that people had upgraded to the ZF rack.

 

[SolidState]

you would think that all it requires is a calibrated signal, so theoretically you could run the ZF SARC rack through a VSS...

 

[naval-avi8or]

With the exception that the connectors might not be the same the racks should be interchangeable. Both racks recieve the same inputs from the control modules. The only differance is where the modules recieve their speed signal. Gen 2 from the VSS, Gen 3 from the GEM. The service manual doesn't even show the SARC module in the loop bit it also refers to a VSS which is only on non SHO Taurus. If I remember correctly those who have forced their struts into hard mode by disconnecting the SARC module affected their VAPS and that indicates that the SARC contoller supplies the VAPS with its speed signal. As well non SARC 99's have the SARC module and I would guess thats for VAPS controll.

However the most important part is that VAPS sends the same info to both racks. They each have a primary and auxiliary actuator, and as speed increases they gradually open the auxiliary actuator to control power steering assist.

 

[naval-avi8or]

With the exception that the connectors might not be the same the racks should be interchangeable. Both racks recieve the same inputs from the control modules. The only differance is where the modules recieve their speed signal. Gen 2 from the VSS, Gen 3 from the GEM. The service manual doesn't even show the SARC module in the loop bit it also refers to a VSS which is only on non SHO Taurus. If I remember correctly those who have forced their struts into hard mode by disconnecting the SARC module affected their VAPS and that indicates that the SARC contoller supplies the VAPS with its speed signal. As well non SARC 99's have the SARC module and I would guess thats for VAPS controll.

However the most important part is that VAPS sends the same info to both racks. They each have a primary and auxiliary actuator, and as speed increases they gradually open the auxiliary actuator to control power steering assist.

OK I went to the electrical schematics which I hate to read but it clearified all the info

GEN 3 has no stand alone VAPS controller it's intergrated into the SARC module.

 

[Mr Anonymous]

OK I went to the electrical schematics which I hate to read but it clearified all the info

GEN 3 has no stand alone VAPS controller it's intergrated into the SARC module.

Correct.

All the V6 cars with the V8 subframe and a ZF rack we've done do not have VAPS enabled. Since all of the cars so far with the V8 subframe setup have been cars that are driven on tracks alot, it's never been an issue. The typical V6 driver who might like to have VAPS would most likely not drive the car in a way that they would see any benefit to a V8 subframe and ZF rack.

 

[naval-avi8or]

I have the full V-8 system in my 94 and it is definitely better than the old V-6 system. It handles much better than before. It'll be interesting to see how much the SARC struts play into that since I've removed them. I'll have the Non SAC struts back in by next week (thanks to missing hardware).

 

[naval-avi8or]

I also wondered if the front track width was wider on the Gen 3.

I just found it. Its the same on the front 61.6" , backs are different Gen3 being .6 inches wider @ 60.5"

 

[shobote]

Well guys before my car exploded it used to nose dive a decent amount. Its got koni/eibach with a 24/26 combo. I don't have bias plugs or anythign like that and was wondering if there was anything I could do to make it stay flat while braking. My buddies bmw stays so nice and flat while braking im really jealous. Course thats a rwd and doesn't have such a heavy front end could that be part of the problem and would bias plugs help? Im also thinking of cutting one coil off my front springs before putting my car back together would that help any or make it worse? Im doing it because my front wheel gap is bad even with stock size slicers on it, my summer wheels just make it even worse.

EDIT: I do have the 12.5" baer pbr kit up front and the 11.6" rear kit

Guess this thread has wandered from the original subject a bit; Are you using the original calipers on the rear ? Check to make sure they are functioning properly; i.e, check the slider pins in particlular. Nosediving tells me the fornts are doing all the work and the rears are not doing their part.

 

[1993MTXSHO]

Guess this thread has wandered from the original subject a bit; Are you using the original calipers on the rear ? Check to make sure they are functioning properly; i.e, check the slider pins in particlular. Nosediving tells me the fornts are doing all the work and the rears are not doing their part.

hmmm, ya know I did just replace one of the rear calipers because it didnt work after the accident, but who knows if it was working before it, maybe that was my problem. I only got to drive the car lie k500 miels after my accident before the engine blew up and never did any hard brakign so I guess ill find out if that was part of the problem when I get the car together. Also yes its the stock 92 caliper with 11.6" rotors

 

[Todd TCE]

Fitting the bias plugs is not going to prevent the car from nose diving. Wheight shift is still weight shift. Should you do this you may find the rear is more "twitchy" and you feel it rotates better (assuming you're ready for it) and allows you some improved turn in, however it won't alter the weight shift.

Some revrerse rake and shock/spring work will help you control the rate at which that weight is transfered. Even putting some balast in the trunk might be worth a try.

 

[1993MTXSHO]

yeah I guess I wont cut my front spring then, and I do have like 80 lbs of stereo in my trunk so that might help keep the rear down.