Couple brake and suspension questions

[Techspy]

My 94 S4 has a manufacture date of Oct 93 and it has the non-Brembo brakes. So I need to replace the front rotors (wobble in the steering wheel under braking) and found 2 different models of EBC rotors. I assume one is for the Brembo and one for the non-Brembo but they don't specify.

 

Here is the one I think is for the Brembo system; http://www.amazon.com/EBC-Brakes-GD1130-Dimpled-Slotted/dp/B003I8ECUA/ref=sr_1_1?s=automotive&ie=UTF8&qid=1389653370&sr=1-1&keywords=EBC+Brakes+GD1130

 

And the one for the non-Brembo system; http://www.amazon.com/EBC-Brakes-GD323-Dimpled-Slotted/dp/B004AHTDFC/ref=sr_1_2?ie=UTF8&qid=1389654261&sr=8-2&keywords=gd323

 

And here is a pict of my current EBC rotors (don't have the receipt to look for the model number)

 

 

 

So can anyone confirm that the correct rotor is the GD323?

 

Also, I have sourced a set of Gaz shocks and they told me that they are designed to fit the "Standard 3 inch springs". I am guessing that means the factory tapered end springs? If so, what is a good source for a set of springs? I want standard street or maybe one level more aggressive. I got a quote from Dave Bean and was quoted around $157 a pair for the rear and almost $900 a pair for the front!

 

Thanks, John

[sanj]

So can anyone confirm that the correct rotor is the GD323?

 

Looks correct, though Amazon seems to disagree. How did you find that part number?

Edited January 14, 2014 by sanj

[Vulcan Grey]

Wobble under braking could also be a worn steering rack, or worn bushings, bad alignment, or loose bearings...

 

Oh and those rotors are Waaaaaaaaay overpriced!  I would not buy those.  For a street driven car, I would buy the standard '84 Celica rotors over those slotted and dimpled rotors.  Those slots and dimples aren't sharp enough to do any good, and will only cause future problems anyways.  Get the $20 Bendix rotors...

 

If you plan on tracking your car, then look at a full upgrade, since the original calipers, pads, and rotors aren't up to the job no matter what you change...

[Techspy]

Thanks Sanj.

 

Well, it is rotational related as it slows down with each revolution until I stop. Most likely rotors correct? The steering is nice and tight by the way and I am going to be replacing all bushings soon too.

[sanj]

Upon further examination, I think the GD323 is the rear rotor for a Celica. You need the front.

[Techspy]

Hmm, from everything I have been able to find out they don't make the dimpled/slotted for the rear anymore. I got that part number from the EBC website. They have an 85-94 part (this one) and a 94-96 so I figured mine would be the 85-94 model being it was made Oct 93 and is non-Brembo.

[Vulcan Grey]

Well, with slots on your rotors it would be hard to tell what vibration is due to the slots and what is due to the pad deposits...  Usually rotors don't actually warp, the problem is usually due to un even pad material or rust deposits from holding the brakes afte r ahard stop or washing the car and letting it sit, or similar.  You can sometimes clean the deposits off by performing in a re-bedding process.

 

Read this and give it a try before springing for new rotors

http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths

[Techspy]

Thanks I will take a look at that. FYI, the rotors look very clean and they didn't have this issue when I installed them years ago. Only noticed it since I purchased the car back recently.

 

The thing that has me convinced is that as I slow and get close to stopping I can feel that there is more "grab" in one spot as the wheel rotates to a stop. like I am pressing the brake harder for a split second and letting it back out again. Always at the same place as the wheel rotates.

Edited January 14, 2014 by Techspy

[sanj]

Hmm, from everything I have been able to find out they don't make the dimpled/slotted for the rear anymore. I got that part number from the EBC website. They have an 85-94 part (this one) and a 94-96 so I figured mine would be the 85-94 model being it was made Oct 93 and is non-Brembo.

 

OK, I was thrown off by the photo, which looks nothing like your rotor. A check at a couple of other sites seems to back you up.

[Techspy]

Thanks Sanj.

 

Travis, I thought the Celica rotors were for the Bembro cars only? Do you have a part number for those?

 

I really like the look of the slotted/dimpled and have drilled on the rear and wanted a better match than solids. Heck, i even have a full set of solid rotors in the shed. They are used but I don't think very much. Maybe I will just put the fronts on to verify that the issue goes away.

Edited January 14, 2014 by Techspy

[Vulcan Grey]

Drilled is worse for pad wear, heat distortion, and cracking!

 

Smooth is best for street.

 

Slotted is best for race, worst for pad wear, but the slots should be sharp enough to cut your hand.

 

The 89-94 non Brembo use the Toyota rotors in the front with toyota calipers and bearings.

[Techspy]

Thanks for all the info guys. I have a plan of attack and know what I need to get if I go to change the rotors (looks like there isn't many options for the rear however).

 

So, any suggestions on springs?

 

Thanks!

[Vulcan Grey]

I think the original Lotus Esprit progressive springs with aftermarket adjustable dampers felt nice, otherwise springs are a real crapshoot...

[Techspy]

Thanks Travis. I think I will go with the Eibach from JAE and the GAZ dampeners. It looks like the spring seats on my AVOs will work on the GAZ.

 

Also, I read that writeup on the brake vibrations and have a few things to report;

 

- My ABS works great

- My Esprit brakes completely straight even when you push the pedal through the floor.

- Travis is a virtual encyclopedia of automotive and especially Lotus knowledge.

- I get kinda dizzy stopping that fast

- The suggestion worked. After about 4 full power stops from about 65-20mph, virtually all of the vibrations/steering wheel wobble is gone during braking of any degree (slight to full bore).

 

Thanks Travis!