13" Cobra + Q45 / J30 Caliper upgrade possibility
02-14-2006, 04:05 PM
#245
Originally Posted by gen4maxima536
what components are you using?
also a question.. if we use Jeffs brackets we can use the J30 TM without milling down the J30 rotors?
also a question.. if we use Jeffs brackets we can use the J30 TM without milling down the J30 rotors?
13'' Cobra rotor
90-96 Q45 Caliper
02-15-2006, 10:26 PM
#248
Junior Member
Join Date: Feb 2006
Posts: 24
Originally Posted by Kevlo911
Read the entire thread...
Also, do you think the spacer would be necessary if runnin the smaller rotors??
02-16-2006, 12:47 AM
#249
Senior Member
Join Date: Mar 2002
Location: chicago IL
Posts: 661
you cannot use the J30 and the Max rotor in any circumstances... this is because if you did, the pistons on the caliper would have to come out of the body way more than there made to in order to pinch the pads on the thinner rotor. this could damage the caliper. that is why if your going to use the j30 caliper, you must use the rotor that is made for the caliper, or at least a roter of very similar thicknesses.
02-16-2006, 10:56 AM
#250
I think he is asking about using the 26mm 300ZX rotor since it is the same diameter as the Q45/J30 rotor but less thickness. The Q45/J30 rotor is 28mm thick and 300ZXs have either 26 or 30mm. Using the 26mm would probably reduce the amount of grinding on the inside of the torque member, but at the expense of longevity of the rotor. It would also be lighter. You would still need to grind the diameter most likely.
02-16-2006, 08:11 PM
#251
Junior Member
Join Date: Feb 2006
Posts: 24
Ok, since there is probably still a need to shave might as well just get the J30 28mm rotors. In anycase, what about the spacer, since there is a need for one cause of the centering to push the rotor outward slightly... stacking up washers to push the TM backwards 1/16" to center the rotor. Wouldnt that work as well?
02-17-2006, 07:42 AM
#255
Originally Posted by Kevlo911
Karim, hurry up and install these so I can see if I want the same setup 
02-26-2006, 06:36 AM
#256
Moderator who thinks he is better than us with his I30
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Well, the J30 coversion is out of the picture for me.
With the first set of calipers I got the left was the wrong part. Returned and reorderd. Went yesterday to pick it up and it was wrong again. Ended up just getting a refund for the whole thing and just installed the Hawk pads with stock rotors and calipers. Was just sick of messing with it.
So....I have a set of brand new Brembo J30 rotors and the spacers needed for the swap. Can't return them, so looking to get rid of them. Got them from TireRack, listed at $61 each. Will sell the rotors and spacers for $100 + shipping. Rotors have never been used.
I also have the stock torque members modified to work with the J30 rotors. They are currently on my car, but am willing to sell them as well if someone can provide me with their stock unmodified TM. Resonable turnaournd if someone wanted them. Will sell the TM, J30 Brembo rotors, and spacers for $140 + shipping.
With the first set of calipers I got the left was the wrong part. Returned and reorderd. Went yesterday to pick it up and it was wrong again. Ended up just getting a refund for the whole thing and just installed the Hawk pads with stock rotors and calipers. Was just sick of messing with it.
So....I have a set of brand new Brembo J30 rotors and the spacers needed for the swap. Can't return them, so looking to get rid of them. Got them from TireRack, listed at $61 each. Will sell the rotors and spacers for $100 + shipping. Rotors have never been used.
I also have the stock torque members modified to work with the J30 rotors. They are currently on my car, but am willing to sell them as well if someone can provide me with their stock unmodified TM. Resonable turnaournd if someone wanted them. Will sell the TM, J30 Brembo rotors, and spacers for $140 + shipping.
03-02-2006, 07:12 AM
#257
Mild Update:
I got re-manu'd calipers from Autozone yesterday. 100 bucks for the pair...only thing is that they didn't include the TM. So i have take the TM off of my old set of Q45s in order to get my core exchange fee back. My car is at the mechanic's today. I asked them to take off the TM to me. I hope they do.
I have everything i need for the swap w/ the exception of new bolts, washers, lock nuts etc...
I got re-manu'd calipers from Autozone yesterday. 100 bucks for the pair...only thing is that they didn't include the TM. So i have take the TM off of my old set of Q45s in order to get my core exchange fee back. My car is at the mechanic's today. I asked them to take off the TM to me. I hope they do.
I have everything i need for the swap w/ the exception of new bolts, washers, lock nuts etc...
03-02-2006, 09:27 PM
#259
would running q45 calipers on 04 rotors be worth it, i thought the 04s rotors were the same thickness as stock rotors just larger diameter. so according to what i think i read, thats too thin to work casue the piston would have to go out too far casue the q/j use wider rotors as opposed to larger dia like most of us are running, is that correct? i. and im running a set of 04 rotors and brackets and id like to add my new set of q calipers if theyll all paly well together. if the rotors too thin, couldnt i just use soem type of spacer to made the pads thicker, ive never heard of anythng like that tho.
03-03-2006, 06:21 AM
#260
Moderator who thinks he is better than us with his I30
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Originally Posted by ColdSHO
would running q45 calipers on 04 rotors be worth it, i thought the 04s rotors were the same thickness as stock rotors just larger diameter. so according to what i think i read, thats too thin to work casue the piston would have to go out too far casue the q/j use wider rotors as opposed to larger dia like most of us are running, is that correct? i. and im running a set of 04 rotors and brackets and id like to add my new set of q calipers if theyll all paly well together. if the rotors too thin, couldnt i just use soem type of spacer to made the pads thicker, ive never heard of anythng like that tho.
If indeed the 04 rotors are the same thickness as stock 4th gen then yes, they would not work. The caliper piston would have to travel too far.
I have J30 rotors and the spacers need for sale.
03-03-2006, 02:43 PM
#262
Junior Member
Join Date: Feb 2006
Posts: 24
I hope to have this on my G20 in a week or so. I have to say Jeff is the man for these brackets. A lil over 200 for everything is worth it for the extra braking power. Anyone else who is interested check out www.rockauto.com for blank Cobra rotors. $65 shipped!
03-03-2006, 09:02 PM
#264
I am as positive as I can be without having actual proof infront of my eyes that the 2k4 rotors are thicker than stock 4th gen rotors. I'm looking for thickness specs right now but not coming up with much yet.
03-04-2006, 07:50 PM
#268
so, would the 04 rotors be wide enought to use a j/Q caliper?
im useing my stock 5.0gen caliper on them now, i figured if the 04s were wider than my stockers my stock calipers wouldnt work properly.
are my stock 00 rotors wider than 4th gens, i thought they were the same.
im not totoally ruling out he idea of spacing the pads. typaicall ythe backing of most pads is about 2mms thick. is i add one of those from lets say a stock pad and soemhow fasten it to the new pad in a way where they couldnt possibley seperate, then in theory it could work.
another thought...when a pad wears down the piston has to push farther. the difference can be up to 10mms under extreme conditionsfrom what iv noticed, im sure the piston is made to be able to accomidate wear to almost that extreme. if i just keep nonworn down pads, wouldnt the piston not have to travel as far, therefor allowing me to use q/js on 04 rotors.
i really dont want to get the z calipers id liek to be able to throw my stock rims back on if i needed to.
im useing my stock 5.0gen caliper on them now, i figured if the 04s were wider than my stockers my stock calipers wouldnt work properly.
are my stock 00 rotors wider than 4th gens, i thought they were the same.
im not totoally ruling out he idea of spacing the pads. typaicall ythe backing of most pads is about 2mms thick. is i add one of those from lets say a stock pad and soemhow fasten it to the new pad in a way where they couldnt possibley seperate, then in theory it could work.
another thought...when a pad wears down the piston has to push farther. the difference can be up to 10mms under extreme conditionsfrom what iv noticed, im sure the piston is made to be able to accomidate wear to almost that extreme. if i just keep nonworn down pads, wouldnt the piston not have to travel as far, therefor allowing me to use q/js on 04 rotors.
i really dont want to get the z calipers id liek to be able to throw my stock rims back on if i needed to.
03-06-2006, 08:20 AM
#271
I went ahead and shipped them priority for you. Shipped sat. Note your trader rating also.
Originally Posted by uglee_t
I hope to have this on my G20 in a week or so. I have to say Jeff is the man for these brackets. A lil over 200 for everything is worth it for the extra braking power. Anyone else who is interested check out www.rockauto.com for blank Cobra rotors. $65 shipped!
03-08-2006, 12:47 PM
#272
You just received thethe brackets/rings. Let me know how they work out 
Originally Posted by uglee_t
The 2k4 rotors are definitely thicker then the 4th gens. 4th gens use 22mm thick rotors or .87 I believe.
03-09-2006, 09:33 AM
#275
Moderator who thinks he is better than us with his I30
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Originally Posted by muradk
guyz can anybody tell me if upgrade to J30 rotors and calipers actually improves our braking??? and where do those spacers go?
03-09-2006, 02:07 PM
#279
Upgrading the rears just for the thicker rotor is a waste of time IMHO. I'd say it's almost impossible to brake fade the rear maxima brakes. The bias just ins't enough to heat them up that much. If you did manage that, your fronts would be crying for mercy long before.
03-11-2006, 05:15 PM
#280
Ok re-reading thru the tread.
I know I'm beating a dead horse, but correct me where I'm wrong.
Say I just heard of this swap and wanted to do it. Things I would need:
Z/J/Q Rotors ( I have Z rotors 280mm x 30mm)
If I didnt want to shave the TM, I would mill my Z rotors down to 280mm x 26mm)?
If I Shave the TM, I would still need to mill the Z rotors (... x 30mm down to 26mm). Or buy some J/Q Rotors.
Use Maxima TM or trash it and buy J/Q TM?
Brake pads based on answer to above ^^ question
Spacers to go on each stud (behind the rotor?) 1/16" wheel spacer? I assume a regular washer would be too weak for this instance.
Regular Maxima lines would work or SS lines from Matt?
I know I'm beating a dead horse, but correct me where I'm wrong.
Say I just heard of this swap and wanted to do it. Things I would need:
Z/J/Q Rotors ( I have Z rotors 280mm x 30mm)
If I didnt want to shave the TM, I would mill my Z rotors down to 280mm x 26mm)?
If I Shave the TM, I would still need to mill the Z rotors (... x 30mm down to 26mm). Or buy some J/Q Rotors.
Use Maxima TM or trash it and buy J/Q TM?
Brake pads based on answer to above ^^ question
Spacers to go on each stud (behind the rotor?) 1/16" wheel spacer? I assume a regular washer would be too weak for this instance.
Regular Maxima lines would work or SS lines from Matt?