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Luisv
02-04-2014, 10:11 PM
I have a 2002 GTS.

I've gotten to the point that I'd like to upgrade the brakes. The stock units are OK but can be improved a bit with an upgrade. I've decided to go the SRT10 front upgrade and taking the GTS fronts to the rear.

As part of that I'll be replacing the rotors. I am going with slotted rotors as I do not like cross drilled rotors. At most, I may go with dimpled. It's a performance/durability thing. Not asthetic.

I've been searching around and I've seen options. EBC, StopTech, Centric and Baer. In the process I found the offerings from Roe. They look excellent for the price. I was looking at the two peice units as well.

Question has anybody used them? The one or two piece Roe's? On the two piece, how durable are those hats?

Any help/opinions/suggestions would be really appreciated.

I've purchased some items from Roe before... Loved dealing with them. Just wanted to check what the feeling is on these in-house rotors.

Dan Cragin
02-04-2014, 11:10 PM
You might want to reconsider putting those front calipers on the rear. It will work and you will have better rear brake torque, but the piston size of the front calipers is much more than the current rears. The result is quite a bit of brake pedal travel, which takes time too get used to. First impression is that the car wont stop, until you get hard on the brakes. Changing the master cylinder bore size can help, but all brake systems are designed with smaller caliper pistons in the rear and bigger in the front.

Just my experience, yours may differ.

Fatboy 18
02-05-2014, 05:47 AM
I think MADMAX has the Roe 2 piece discs fitted on his GTS, No problem with them at all :)

I have the Baer Erradispeed Discs fitted to my car, mine are currently drilled and slotted but when I replace the discs again I will go slotted only.

I do know of a UK Viper owner who had the EBC dimpled discs crack on him! (that was on stock Gen II)

I do believe you have to OR it is advisable to fit a brake Bias balance valve to regulate pressure between front and rear.

Ipsco makes parts and a very nice rear Handbrake calliper :)

Luisv
02-05-2014, 07:33 AM
You might want to reconsider putting those front calipers on the rear. It will work and you will have better rear brake torque, but the piston size of the front calipers is much more than the current rears. The result is quite a bit of brake pedal travel, which takes time too get used to. First impression is that the car wont stop, until you get hard on the brakes. Changing the master cylinder bore size can help, but all brake systems are designed with smaller caliper pistons in the rear and bigger in the front.

Just my experience, yours may differ.

The later Gen 2 cars have a bigger master, if my homework found the right info, because of the ABS. My understanding is that the master on my 2002 is the same as that on the Gen 3 and 4. The rear caliper on the Gen 2, also made by Brembo even though it is a single slider, is a 36mm piston. So, in the end, you are absolutely right, the brake pedal will travel more because I am essentially doubling the rear piston volume (Gen 2 fronts are 42/38 pistons).

I will have to get used to it, but I will say that more brake pedal travel would not hurt, in my opinion. The travel is basically nothing now. So for me, I'd like a bit more to be able to control the pressure applied a bit more.

Good thing about the change that I am planning is that the Viper design team, when upgrading the Gen 3 brake system, went with this setup. A gen 3 has 44/40 front calipers and 42/38 rear calipers. Making this change I, basically, get the same setup. The only difference is that the rear would be a 13" rotor in my case. Since the rear accounts for less than 25% of the braking, it'll be fine.

Great point! Thanks!


I think MADMAX has the Roe 2 piece discs fitted on his GTS, No problem with them at all :)

I have the Baer Erradispeed Discs fitted to my car, mine are currently drilled and slotted but when I replace the discs again I will go slotted only.

I do know of a UK Viper owner who had the EBC dimpled discs crack on him! (that was on stock Gen II)

I do believe you have to OR it is advisable to fit a brake Bias balance valve to regulate pressure between front and rear.

Ipsco makes parts and a very nice rear Handbrake calliper :)

Thanks.... I don't have to worry about the bias. The 2002 has ABS so the brake system will manage the potential for rear lockup. No need for a bias control on the 2001 and 2002...

MtnBiker
02-05-2014, 08:31 AM
JonB has the rotors that came off the ACR-Xs when they came off the assembly line. They are basically the same as what come on the SRT10 coupe. Not slotted, but not expensive.

Bill Pemberton
02-13-2014, 04:13 PM
I would definitely listen to Mr. Cragin, as he is a shy young man, but he is arguably the best Viper Tech in the entire US of A!!!
His advice can be counted on as very solid. Frankly you would be surprised how much better the car would stop with just better front rotors and a brake duct kit. The Gen IIs biggest issue was just
getting air to the rotors.

IndyRon
02-13-2014, 05:29 PM
Maybe I'm missing something, but why not just upgrade to a complete Gen 3 or 4 front and rear setup? Saves messing with the bias and you get better brakes for cheap as many of these cars are being parted out after wrecks.

JonB ~ PartsRack
02-13-2014, 07:30 PM
What Dan Cragin said is important insight, and Ill add this: The target 85-15 balance is waaaay over-braked at the rear, even (especially) if you have to rely on ABS to correct the imbalance!

THE YEAR MATTERS and your research and empirical results are correct for 2001-2002. OTHER OWNERS SHOULD NOT APPLY THIS LOGIC TO OTHER YEARS!!! But the logic that ABS will make it all OK is not fully accurate.

For example, what if the ABS has its normal job to do during compromised traction, and now also has to correct the imbalance? The result is still a tank-slapper.

If you track the car (you did not say) you would do well to lower the friction at the rear by a pad choice.

Your original question about rotors may still be hanging..... lots of options and you usually get what you pay for.

On the MtnBkr referral (TNX) above, YES, PartsRack did buy the ACR-X take-off parts: A/C stuff, compressors, condensors, some interior stuff, and 50 sets of OE SRT10 Front Brembo Rotors with 5-7 miles on them! Offered at only $125/pair !

Luisv
02-16-2014, 09:33 PM
Maybe I'm missing something, but why not just upgrade to a complete Gen 3 or 4 front and rear setup? Saves messing with the bias and you get better brakes for cheap as many of these cars are being parted out after wrecks.

Well.. that's essentially what is happening. The front calipers on the Gen 2 are 42/38 piston calipers. The rear on Gen 3 and 4 are 42/38 calipers. They are essentially the same. The only difference is that on a Gen 3 is that the rear is on 14" rotors. What I am doing is going with the 13" rotors. I will have slightly less brake torque than a gen 3.

As for not messing with bias.... Going with Gen 3 brakes all around would not eliminate this need. The ONLY the case where you would not need to worry about bias change is with ABS Gen 2 cars. Non-ABS Gen 2 cars will REQUIRE brake bias adjustment added to the car. If not the rear will have too much braking and the rear will come around if you are too hard on the brakes.

Luisv
02-16-2014, 10:22 PM
What Dan Cragin said is important insight, and Ill add this: The target 85-15 balance is waaaay over-braked at the rear, even (especially) if you have to rely on ABS to correct the imbalance!

THE YEAR MATTERS and your research and empirical results are correct for 2001-2002. OTHER OWNERS SHOULD NOT APPLY THIS LOGIC TO OTHER YEARS!!! But the logic that ABS will make it all OK is not fully accurate.

For example, what if the ABS has its normal job to do during compromised traction, and now also has to correct the imbalance? The result is still a tank-slapper.

If you track the car (you did not say) you would do well to lower the friction at the rear by a pad choice.

Your original question about rotors may still be hanging..... lots of options and you usually get what you pay for.

On the MtnBkr referral (TNX) above, YES, PartsRack did buy the ACR-X take-off parts: A/C stuff, compressors, condensors, some interior stuff, and 50 sets of OE SRT10 Front Brembo Rotors with 5-7 miles on them! Offered at only $125/pair !

OK. Question... Not to challenge... But honest question. If I am wrong someplace, I need to know...

Why would this setup work on the Gen 3/4? The brakes are the same as what I am considering. In short, the Front is a 40/44 caliper with a 42/38 rear caliper. The master cylinder is the same as the ABS Gen 2 master. In fact, the 13 inch rear rotors vs. the 14 inch gen 4 would give me lower rear brake torque.

Is the ABS completely different in 2003 from what it was in 2002? Is the bias on a Gen 3 90/10? How is it that the Gen 2 ABS will fall short?

As for tracking the car, I don't plan to, but would if the opportunity arises. Bottom line, the car will be street driven 90% of the time. I don't want that to translate to assuming the car will not be driven hard. The car does go on a number of mountain road cruises and lets just say it's not for the scenery.... ;-)

As for what Dan had mentioned re the additional brake pedal travel... I agree... No question. However, a bit more travel to modulate a bit better would be good.

Thanks in advance for the info!

Luisv
02-16-2014, 10:30 PM
Getting back to the original question.... I'll add some more info...

I would prefer:

Slotted rotors over cross drilled. Dimpled would be OK if this is the only option. I would not go cross drilled.
Two piece would be great if the replacements are available. I think we are limited, particularly, with the 13 inch Gen 2 fronts (being used in the rear).
I'd like to go with the same rotors front and rear.

So what rotors have you all used? What are the recommendations?

Thanks folks...