When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I am measuring the total height of the rotor From the back side of the rotor to the front wheel side. I found the 1.87" height of the OEM (93-97) from the lukestaff website.
I also called Ed Miller a little while ago and his wife answered the phone. I was shocked!!!!!! He wasn't there so she asked to take a message. I told her I had been trying for months to get in touch with him and had left numerous voicemails on the phone. She replied back with " that's not true. I screen all his calls and he replies back to everyone within 24 hours". I told her I left a message on january 3rd and she said I didn't. Then she said "listen, I'm not going to argue with you, give me your number and I'll have him call you back!". She was extremely rude!
I guess I will wait and see if he even gets the message now.
Im wondering if I could get away with using OEM (93-97) backing plates and crossing my fingers that Baer still has those adapters in stock. This is now going to be a guessing game on what I need to do in order to use these rotors. Baer now supplies brand new backing plates with the 13" rotors so I'm baffled as to what the difference is between someone with a 93-97 disc car using this kit and someone with a 3rd gen drum rear using this kit.
Last edited by BOTTLEDZ28; 02-05-2017 at 10:48 AM.
lay a strait edge on the back of the rotor and measure to the axle side of the hat. that will be the same as factory. top of hat to rear of rotor will be very different and doesn't matter.
lay a strait edge on the back of the rotor and measure to the axle side of the hat. that will be the same as factory. top of hat to rear of rotor will be very different and doesn't matter.
1.87". Thanks for pointing out my measuring mistake. I assumed these rotors were measured from one side to the other.
I just need to figure out the offset needed to have a new backing plate made or modified. Or use the OEM 4th gen ones and see if I can then get Baer to send me the adapter pieces for the 13" rotor option,
I tried an experiment and this is the end result..
I put the OEM wheel spacer on the axle flange and then put the rotor on. This moved the rotor out enough so I could slide the abutment bracket and bolt it to the backing plate. Everything looks good in that area but I wont know for sure until I get it on the road. I do not like this method to fix the problem either. As of right now, Im just experimenting with options.
The downside to adding the spacer behind the rotor is that it pushes the wheel out and reduces the length of the threads on the wheel studs. I can also install longer studs but I really dont want to if there are other options here.
I've seen some cars have shims behind the rotors before. I guess some of the rear tubes were either cut wrong, or plug welded into the diff wrong, you could have something like that going on and with the drums it wasn't really an issue.
The rotor is still too close to the abutment bracket, it will probably rub. I think the only other thing you could probably do is more spacer behind the hat, or have the factory bracket flange ground down.
You should probably go with longer studs since the aluminum wheel is thicker than stock and you have that aluminum hat on there with also takes away more usable thread.
I wonder if you issue is because you started with a drum rear end. You axle flanges obviously aren't the same as the disc rears and I wonder if the spacing is different. I bought my Baer kit maybe 12 years ago and it came with the cadmium plated brackets shown in your second pic above. Everything bolted up with the correct spacing.
I wonder if you issue is because you started with a drum rear end. You axle flanges obviously aren't the same as the disc rears and I wonder if the spacing is different. I bought my Baer kit maybe 12 years ago and it came with the cadmium plated brackets shown in your second pic above. Everything bolted up with the correct spacing.
The drum rear to disc swap has been done over and over again on this forum without issues. It has also been done,without issues, using Eds Hassle Free backing plates. This is what has me stumped at the moment. The only difference between a stock rotor and the Baer rotor I am using, is the diameter. I double checked the height of mine and compared it to the known documented height of a stock 4th gen rotor and it is the same.
I may call Baer today and see what they have to say BUT they are going to wash their hands of this once they find out that I am trying to put a 4th gen Fbody brake upgrade kit onto a 3rd gen Fbody drum axle with "homemade" backing plates.
I am waiting for Ed call me back today but I'm afraid that my message wont get to him considering his wife or girlfriend was extremely rude to me on the phone yesterday. She called me a liar when i told her I had left numerous voicemails on the machine and sent a handful of emails. Funny how my phone has call log records which clearly show outgoing calls made to his business. I also have Sent emails going back to Feb of last year! But I guess my phone is lying too.
As to what I am going to do here, I have no idea. I really do not want to run that OEM spacer between the axle and the rotor. This will require me to replace all 10 axle studs with longer ones. Not exactly what I want to do right now.
And, I am not even sure that using that OEM spacer is going to center the caliper over the rotor. It may look good to the eye or in the picture but that needs to be perfect.
The factory disc bracket has a slight offset to it and I'm guessing that's some of the issue.
I wouldn't run that spacer under the rotor either.
Yes, the factory backing plate does have an offset but the plate itself is 3 times as thick as Eds. I bet the offset difference is the same difference between the thickness of the OEM bracket and Eds bracket. This is why Ed just made flat plates but at 1/3 the thickness. In the end, it must all be the same.
And even if it did have an offset, why would it be making a difference on my swap and no one elses? My rotors are the same height as OEM rotors. They're just a bigger diameter, which is compensated for in EDs hassle free bracket. If I was running stock rotors and bought Eds stock hassle free plates, I would still have the same problem as I do now. I'm just at a loss here because I have gone over this swap in my head for a year. This was supposed to be a Hassle Free swap. My fingers are crossed that Ed calls me back AND has some sort of solution for me.
And for the record here... is the distance from the drum flange to the end of the axle tube the same as the disc?
And for the record here... is the distance from the drum flange to the end of the axle tube the same as the disc?
Fairly certain It should be within a shim-able distance. All the ones I have done were.
Unless someone has swapped in a axle that is a bit shorter than factory you shouldn't be having any issues.
This is beginning to give me a stomach ache I have $1,000 into this swap right now and Ive hit a brick wall. Baer is currently looking at the pictures I sent them but Im not to sure they can help me.
This is where I bought the Baer kit from
I just received an email reply from Baer. I had a feeling they would say this if they didnt have a logical explanation for this.
......I believe what your running into is that the 2 rear ends had a different axle offset.
We’ve never had an issue with fitment on the 2302048 when on the correct rear housing.
This may be able to be corrected by getting a shorter depth rotor hat which will bring the rotor outward.
This was not designed for the housing your using with the different offset.
So I just found this thread where someone had a similar issue. It appears that there is actually a difference between the 3rd gen and 4th gen housing between the end of it and the backing plate flange. Looks like 3rd gen is slight shorter which may be the reason why these 4th gen rotors are not working on this 3rd gen axle. Weird. Looks like I may have a pair $600 paper weights now!!!! Cant return them. I bought them back in the beginning of December!! Maybe is Ed was a little better at replying back to customers and shipping his crap out in a timely manner, I could have found this problem with my return window for the Baer kit!!!!!!
Baer claims that they did not make a 13" 2pc Eradispeed rotor for the 3rd gens yet Eds website claims he offers one with the 13" rear kit.
The 13" Baer rotors I have here are labeled for a 4th gen (93-97) Fbody. The ones in Eds pic do not look like the ones I have.
I think I found my problem!!!!!!!!!!!!!!!!!!!!!!!!!!
I think I have the wrong rotors. The hats on these rotors are 1.1" tall. There is another 13" Baer rotor that is for the C4 Corvette that has a hat that is .850" tall. That kit is listed in this thread.
Hahahahaha. I literally just laughed out loud. Ive been digging through this forum for over 8 hours today and have been on the phone with Baer at least 4 times, along with sending them multiple emails to try and figure out what the heck is going on here. Then, I find a thread (posted above) and it has a different part number listed for 13" baer rotors. I called Baer and confirmed that the difference between the two rotor is the height of the hat. I will have to spend another $650 now to get the correct kit and hope that I can return the wrong kit. I bought them on 11/29 of last year!!
Last edited by BOTTLEDZ28; 02-06-2017 at 06:25 PM.
I only meant my info was 6 minutes too late to your post.
I know it sucks buying the wrong parts. it doesn't help when you can't use your car to get the info you need for all that.
Did you ask Baer if you can exchange for what you need? If not, you should only need to buy the proper hats and transfer the rotors to those hats, the rotor its self is the same outer dimensions as the C4, as long as both rotors have the same hub mounting pattern
I only meant my info was 6 minutes too late to your post.
I know it sucks buying the wrong parts. it doesn't help when you can't use your car to get the info you need for all that.
Did you ask Baer if you can exchange for what you need? If not, you should only need to buy the proper hats and transfer the rotors to those hats, the rotor its self is the same outer dimensions as the C4, as long as both rotors have the same hub mounting pattern
I can return the first kit I bought. The first kit was $480. I got it on a wicked good promo deal from Auto Anything. They have since raised that priced back up
The replacement kit is $645! I dont have a choice at this point. I need to run the rame style rotors as I am running in the front so it matches.
Baer claims that they did not make a 13" 2pc Eradispeed rotor for the 3rd gens yet Eds website claims he offers one with the 13" rear kit.
Baer definitely made those rotors as that is the kit I bought years ago. When I bought my Extreme+ front kit the best kit they had for the rear was the 13" 2pc Eradispeed rotor with new PBR calipers.
Here's a thought: Will Baer sell you just the correct hats? Since the rotors are 2 piece you could just swap them in to lower the cost.
Baer definitely made those rotors as that is the kit I bought years ago. When I bought my Extreme+ front kit the best kit they had for the rear was the 13" 2pc Eradispeed rotor with new PBR calipers.
Here's a thought: Will Baer sell you just the correct hats? Since the rotors are 2 piece you could just swap them in to lower the cost.
Baer didnt make a 13" 2 pc Eradispeed rotor for the 3rd gens. I suspect that the ones that Ed offers are C4 rotors.
I already ordered a whole new rotor kit from Summit last night. I will return the other kit and just end up paying the difference of $165, which I bet is close to the cost of new hats. I should have the new rotors this weekend so I will be able to compare the difference.
Now you have me wondering which rotor pt number I have on the back of my car. Dutch told me they were C4 based but made for the 3rdgen. Maybe I should rip into my car and do some measuring.
I've never seen that style of hat on a 93-97 4th gen. Looks a LOT taller than any of the rotors I have pulled off. (in link with the rear 4thgen rotors)
Dutch told me they were C4 based but made for the 3rdgen.
Are you saying that the C4 rear rotor is not the same as the 3rd gen rear rotor?
I was under the impression that C4,3rd gen and 4th gen(93-97) all had the same rotor. Maybe I misread something somewhere
Baer did say that the hat on the rotors I have now are 1.1" tall. The C4 hats are .850" tall. So, the ring of the rotor for the C4 kit would move outward 1/4" compared to the Fbody rotor. This may get me to where I need to be.
Last edited by BOTTLEDZ28; 02-07-2017 at 08:46 AM.
Are you saying that the C4 rear rotor is not the same as the 3rd gen rear rotor?
I was under the impression that C4,3rd gen and 4th gen(93-97) all had the same rotor. Maybe I misread something somewhere
Baer did say that the hat on the rotors I have now are 1.1" tall. The C4 hats are .850" tall.
That's what I thought as well.
Its odd that you have the same measurement from the back of the rotor to the back of the hat as a factory rotor and it doesn't work tho. I agree, It has to be in the hat area that's causing the issues.
Well my fingers are crossed that the new rotors will fix this fitment issue. If they dont then I have no idea what I am going to do. Ed never called me back last night, as I suspected. His wife was extremely rude to me on the phone when I said I had been trying to months to get in touch with him. Id love to email here screenshots of all my emails I sent to him since last Feb as well as Sent call logs going back a few months. I wonder if she would still call me a liar then.
Oh, and I bought ebrake cables off him 2 months ago and still havent received them.
This swap should have been a simple weekend job but instead, has turned into a pain in my side.
No the c4 rotor us nit the same. It's a couple mm larger but not much however the offset us different as well. That's why you can run it with flat brackets as opposed to stock stepped
91 1LE, those are the rotors I just picked up from Summit. The kit is advertised for a 88-96 C4 Corvette. I just put one side on a little while ago and it was almost perfect. I had to use the supplied washers and put them in between Eds backing plate and the OEM abutment bracket for the caliper. Looks just about perfect now. I wont know though until Spring.
Here are a few pictures I just took of the rotor and caliper mocked up using Eds 13" Hassle Free backing plates.
You can barely notice the gold colored washer being used as a shim/spacer between the black backing plate bracket and the calipers abutment bracket.
Just enough space so it doesnt rub.
Here is the difference in heights between the Baer rotors for the 93-97 Fbodys ( 6140076) and the Baer rotors for the 88-96 C4 Corvettes (6140071). The Fbody ones have hats that are 1/4" taller than the C4 ones. So, its safe to say that if anyone is wanting to do this swap, DO NOT use the Baer 13" rotor kit for the 93-97 Fbody. They will not work with Eds plates
I had to use a washer as well about the same thickness. The closer to perfectly centered you can get the caliper the better. My stock setup wore pads unevenly and the caliper bracket would actually rub on the rotor with hard cornering. So you ended up with C4 rear rotors? Just in case I need replacements.
Looking at your pics you will definitely have to center the caliper bracket. You can use a thicker washer or you can use shims behind Ed's bracket on the axle housing. Remember with a c-clip axle they move in and out. If the rotor contacts the caliper bracket it will make a very unique sound upon hard cornering.
Looking at your pics you will definitely have to center the caliper bracket. You can use a thicker washer or you can use shims behind Ed's bracket on the axle housing. Remember with a c-clip axle they move in and out. If the rotor contacts the caliper bracket it will make a very unique sound upon hard cornering.
It will be a trial and error thing once the weather breaks. I hope I can get it right on the first assembly. If I have to take out the dremel tool and massage the abutment bracket in a few spots then I will.
Just an update to this thread. I am using the 1NCR5 (19lbs) spring in the stock disc/drum proportioning valve. If it works then awesome. If not then I will step up to the 22lb spring.
Also, Ebrake cables from Ed arrived and have been installed. Getting the old ones out was a PITA with the driveshaft in the car AND being on my back. New cables from Ed have a smaller diameter sleeve so I had to squeeze the S clips in slightly to get the cables to stay in place.
It has been done before, but you are doing things on your own terms, making things work, figuring things out, and not quitting. There are "how-to" threads that help a lot of people. This one takes some reading effort due to the updated parts, but it really is good for those consodering drum-to-disc. Good work!
I got the rear brakes installed and the system bled. Took the car for a ride around the neighborhood for a shake down run and this baby STOPS!! I actually think I have too much brake for this car now. Brakes this large on all 4 corners belong on a car with ABS to get the most performance out of them.
Right now, my only complaint is the calipers on the rear only bite down on half of the Baer rotor. It has left a wear mark on them that now looks funny and I'm willing to bet that its only going to get more noticeable as I put more miles on the car.
02-05-2017, 10:41 AM
