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90 - 91 EX knuckles and 10.2" brakes.

22K views 42 replies 11 participants last post by  mattminerDOTcom 
#1 ·
Well, after having this install on my car for over a month now, I can honestly say that it is one of the most noticeable upgrades that I have ever done on my car...and I'm still using the stock brake pads and rotors that came with the knuckles from the junkyard. I can't imagine how awesome my braking will be once I upgrade the pads and rotors. Everything bolted up perfectly, and I managed to replace a couple of bad balljoints when I swapped out the knuckles and upper arms.

However, one word of warning for anyone considering this swap. The stock 90 - 91 CRX Si teardrops will not fit properly. The calipers grind lightly against the back of the rims. I'm probably going to pickup some spacers so I can still use the teardrops during the winter months.
 
#3 ·
At the very minimum, you need a set of 90 - 91 Civic EX knuckles with brakes and hubs. (ie: knuckles, hubs, rotors, calipers, pads). The 90 - 91 Civic EX was the only EF in North America to have 10.2" brakes, and the knuckles have the SAME suspension geometry as the CRX. This means that it will not throw your alignment settings out of wack. (providing your suspension components or the replacement ones are not bent!). I bought mine from a wrecker near Seattle, WA. They found a set for me from a car that was not in a front end accident.

As a note of interest, the caliper mounting brackets on the EX knuckles are compatible with several calipers from newer generation Hondas. Honda delSol (with ABS) calipers and rotors are a direct swap onto the knuckles. They are still 10.2", but at least it gives you more part options. You can even combine Integra Type R/Accord Wagon calipers with redrilled 94 Prelude VTEC rotors for 11.1" brakes. (some modification required to the caliper bracket to get the offset correct). But for our cars, 11.1" brakes would hinder performance, not help.
 
#4 ·
Would it be possible to grind a very small amount off of the caliper to keep it from rubbing.. we used to do this on out stock cars when we would run weird wheel offset's those old Gm calipers were thick enough that a couple passes with a grinder made just eonugh room. with out hurting the caliper.

Just a thought.

Chris
 
#5 ·
toxiclows said:
Would it be possible to grind a very small amount off of the caliper to keep it from rubbing.. we used to do this on out stock cars when we would run weird wheel offset's those old Gm calipers were thick enough that a couple passes with a grinder made just eonugh room. with out hurting the caliper.
Chris
That's another option. However, how safe is it to be grinding support pieces on a caliper?
 
#6 ·
stickershop said:
toxiclows said:
Would it be possible to grind a very small amount off of the caliper to keep it from rubbing.. we used to do this on out stock cars when we would run weird wheel offset's those old Gm calipers were thick enough that a couple passes with a grinder made just eonugh room. with out hurting the caliper.
Chris
That's another option. However, how safe is it to be grinding support pieces on a caliper?
its not unsafe at all. all you are doing is grinding down a slight bit off the front. many people do this to fit hx rims over these brakes.

however, a new brake upgrade has surfaced that allows the use of 10.2" brakes without the need for the uber rare EX knuckles. in fact you can use the stock US crx si or dx knuckles. all you need are 10.2" rotors for the civic ex, ITR or accord wagon calipers, and then either use a 2-3mm spacer between the hub and rotor, or grind that same amount off of the caliper support bracket. this is the upgrade im going to do. it is recommended to get the 15/16" master cylinder though. brb while i get the link to the thread on hondatech.
 
#7 ·
Jonathan_ED3 from H-T said:
Well guys...you'll be glad to hear that it isn't necessary to hunt down those scarce EX knuckles to upgrade to 10.2" brakes. This bolts onto the non-EX 88-91 Civic/CRX knuckles!

Want to know how it's done?

Read on below to discover the beauty of the Jonathan Mod

Parts list:

-'91 Civic EX Brake rotors...same as 92-95 Civic Sedan rotors ($14.99 each at Pep Boys; probably cheaper at AutoZone)

- Accord Wagon Brake Calipers (will be stamped 17CL15VN; ~$50 rebuilt at Pep Boys). These are the exact same calipers as the ITR, Legend, Prelude VTEC etc. Great stopping power!

- Accord Wagon, Prelude VTEC (etc) Brake Caliper mount stamped 25T (a 23T bracket exists, but I can't promise you it will work). This is what came stock on the Accord Wagon.

- 1/8" wheel spacer OR grind ~1/8th" (2.5-3mm) off of the caliper mounting bracket. If you are familiar with the 11" brake upgrade, this is the same modification necessary.

Now, the installation...

First, you need to place the wheel spacer (or washers if you're ghetto) between the hub and your new 10.2" brake rotor.

OR shave off the ~1/8" necessary from the caliper bracket

Next, Install your rotor, mount the caliper, load the pads....(you know how to do all this) and enjoy your upgraded brakes!!!

I tested these with my two pair of 15" wheels and they fit just fine. If any of you have 14" wheels, you may want to see if they'll clear. They may not.

So you end up with the same rotor surface area as the Integra/EX upgrade, but you're upgrading to ITR quality calipers, larger pads etc. Not too shabby!

The proof is in the pudding....

Note that in these pictures I've got a ~1/10" (2.5mm) spacer between the rotor and the hub. You can instead opt to shave this amount off of the caliper anchor bracket if you don't want to run a spacer




and heres a pic of what the shaved caliper bracket looks like if you want to go this route. this is what i will be doing.


link to original thread: http://honda-tech.com/zerothread?id=1171175

enjoy :). the only thing is i dont think this will fit under a 14" rim, even with grinding down the outside of the caliper. im gonna try it, we'll see.

edit: and am i not allowed to put pics in quotes? i changed them all to url's
 
#10 ·
Yes, I've been following that post on Honda-Tech. I'm waiting to see how it turns out. He test fitted it on a Civic LX sedan, but the last time I checked, he still hadn't actually tried it on a CRX, let alone driven on the setup. I wasn't aware that the Accord wagon caliper brackets actually bolted up to the CRX knuckles properly. I thought the bolt holes were a different space apart. I would want to know for certain that it bolts up properly with all the proper bolts before I gave it a try. I hope it does bolt up fine though, because this will free up more EX knuckles for me ;) I like the fact that the EX knuckles are "beefier" than the CRX ones while maintaining the same geometry.
 
#11 ·
im pretty sure civic and crx knuckles are the same. it will 99.99% for sure fit. im in the process of buying itr calipers with pads and brackets that are already modified. so it should all bolt on no problem with a set of 10.2" rotors from a civic ex. the only thing im worried about is it clearing the 14" wheels.

the main reason this is better is because you dont have to find the rare EX knuckles, and then pay an arm and leg for them, and then have to buy new rotors and calipers. this sves so much time and money, and is an easier installation to boot.
 
#12 ·
well i bought the modified calipers so everythign will be bolt on for me. no spacers :) im gonna try my best to get these under 14" rims. if the only problem is the front of the caliper bracket rubbing the inside of the spokes like on the ex brakes then i should be able to make it work but if the outside rubs the inside of the wheel, then i might be forced to get new wheels. but im crossing my fingers :)
 
#14 ·
justcrx said:
Be sure the change your master too with some stainless steel brake line. You'll feel the difference.
Yes, you should upgrade to a 15/16" master cylinder to accomodate the larger calipers. They can be obtained from an 89 Accord LXi or Preludes from the same years as the CRX.
 
#15 ·
stickershop said:
justcrx said:
Be sure the change your master too with some stainless steel brake line. You'll feel the difference.
Yes, you should upgrade to a 15/16" master cylinder to accomodate the larger calipers. They can be obtained from an 89 Accord LXi or Preludes from the same years as the CRX.
i bought a 15/16" MC from a civic EX. i just have to pick it up from my friends house and bolt it on. and i already have SS lines installed with dot4+ fluid.
 
#17 ·
ok this article got me excited again about a OEM big brake swap. the first time was when I saw Henry do his on crxohio but now KurtW from some of the Honda sites is giving me a set of slotted front rotors from his old 92 civic he says there 10.4 but I think his just mistaken for 10.2. So all i need now is a set of calipers from a Accord Wagon (yr?) and a mount kit which is what exactly? And GSR where did you get already modded calipers locally since you dont live too far away from me I was wondering.
 
#18 ·
Also someone who has read the whole article on H-T can tell me if they ever figured out what mount to use 23t 25 or what someone said 23T might not need any mod to the caliper.Also will the 92 rotor work its the same as a 91 ex right? Tried to read that whole article but it got confusing with all the a$$holes trying to flame the guy for writing the article.
 
#20 ·
dave i got your PM. im using the 23t bracket. and since everything was correct with it already modded, i assume the 23t and 25t are exactly the same in that aspect. now i will have to modify another part of the bracket to make it fit the knuckle. the bolts line up but the bracket is hitting the hub so ill just have to take off a little bit off the inside for it to fit. refer to the folowing pic as to where more material will need to be taken off.



as for fitment under 14's, they will fit under 14's but they rub pretty bad on the back side of the spokes. the needed bracket just sticks out too far forward. for this to work you would have to either use rims of a different offset (i assume something like +38 is ideal) but the crx si rims having +45 is just too much to clear these brakes. if you were dead set on using stock crx rims or any other stock honda 14" rim you could use a spacer to clear the rims. however in doing that you arent left with much stud for the lug to go on so this would only really work safely if you get extended wheel studs. the other option is to take the material off the face of the caliper bracket. again this might not be a good idea because theres not much there and you would have to take off a lot. something i wouldnt wanna do, it might weaken it too much. when it comes to your brakes, safety first! both of these methods are really too much trouble for what its worth to me, im eventually just gonna get a new set of rims to clear these. mostlikely a set of rota's or something. i really liked my black c8's before they were stolen, but maybe ill go with a different set i dont know right now.

dave, as to your question of where i got the caliper brackets already modified, i bought them with new calipers and 2 sets of pads from a guy on honda-tech who had already modified the brackets. he used them on civic ex knuckles to do an 11" brake upgrade. the modification necessary for the 10.2" brake upgrade and the 11" brake upgrade is the same.

anymore questions just ask.
 
#22 ·
a few mm tops. nothing crazy. no pics yet, i havent done it yet.

i do have some more info on the rim clearance of this setup though. the guy who tested this tested with a rim that had 35mm offset. thats a whole 10mm more then the crx si rims. and about the same distance it wouldnt go on the rim. so this upgrade will fit under the 14" rims, but it requies a much different offset. you could run the stock wheels if you ran a spacer and used extended lugs, but thats too much work. im just gonna get a set of rotas or something. 15" rotas usually have an offset of like 38mm. pretty close to what i need. so what im going to do is get rotas. if they still dont clear, then i can take the extra few mm's off the bracket. modifying it only a few mm's is no big deal.

the main problem or vice to this setup is how far out the bracket protrudes. its not flush with the rotor. you can see it in the side shot of the setup that ive pictured.

all in all, the setup is gonna end up costing me more then the ex brake upgrade, but will still be less work and totally worth it IMO. you end up with the same rotor surface area, but with more clamping force and more pad surface area.
 
#24 ·
i only test fitted this on my car. i havent taken the material off the caliper bracket that i need to yet, and i dont have the rims i need yet. the parts are not on my car so i didnt take any pics. ill have pics whenever i get around to getting the new rims, making the necessarry modifications, and then bolting it all up.
 
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