86 9bolt
Lt1 calipes or ls1 calipers do they sell a swap kit or just stick with ebc rear brakes

Can I use dot 5 500+ boiling point

 

With 9-bolt backing plates you could install the correct-sized rotors and either 89-92 or 93-97 PBR calipers. Since the LS1's are designed for a 10-bolt, a bolt-on wouldn't be possible without some kind of modification.

JamesC

 

I found a post awhile saying that the 98+/LS backing plate fit a 9-bolt with just a simple redrilling of the backing plate mounting holes, but I can't find the thread

 

EBMiller makes swap plates for LS brakes, but their production is usually pretty backlogged.

LT1 brakes were the same PBR Caliper as the 89-92 cars got. The only difference is the LT1 calipers have an extra iron dumbbell looking thing hanging off the back that works as a vibration dampener. They're 11.7" discs with aluminum single piston calipers, very effective design. I've been running 94 Z28 rear discs on factory 9-bolt PBR backing plates (found on any 89-92 9-bolt) for 15k miles, and I'm very pleased with them so far. If you're going from '86 discs to LT1 (PBR) style rear calipers, you'll also need a 1LE proportioning valve though.

The big benefit to LT1 over LS1 is that you easily keep your Emergency brake function. IIRC, LS1's are quite tough to get a functioning emergency brake.

-cal30sniper

 

Never seen the backing plate you mention. Link?

IIRC, Ed makes an LS1 parking brake cable.

JamesC

 

I looked through my Bookmarks hoping to find it & share it when I said that above, but couldn't find a Bookmark for it. And I usually very **** about Bookmarking things & organizing it well to be easily found later.

 

Whoops, I was thinking about these three: http://flynbye.com/catalog/c1_p4.html

They're only for PBR/LT1 style setups with different sized rotors though. You might try contacting Ed directly and see if he can make backing plates for a 9-bolt with LS1 brakes. He does make one for Camaro SS brakes on a 9-bolt.

-cal30sniper

 

I will go with lt1 rotors are bigger what's the word with dot 5. Lt1 brakes is a bolt on that's what y'all saing

 

Pretty much but you do have to remove the axles in order to mount the backing plates and so on. The following link may give you the idea:

https://www.thirdgen.org/forums/faq-...iscs-89-a.html

JamesC

 

I did find this pic that I had saved on my PC. The 9-bolt vs 10-bolt backing plate bolt pattern.

 

That pics looks very familiar ! I was talking about an LS1 backing plate, BTW. No such rascal that I know of.

JamesC

 

He used to have them (C5 on 9-bolt) listed, but IIRC the first ones that he made & sent out did not work as expected, so he stopped making them & apparently hasn't corrected whatever the issues were & started making them again.
http://www.flynbye.com/catalog/i77.html

 

I snagged it off TGO. You saying it is LT1 & 9-bolt, not just 10-bolt as the pic indicates? The Lt & LS plates would be different?

 

From the link I posted above apparently. I'm glad you found it useful. The two plates (and there's a side by side pic above as well) are thirdgen, 9- and 10-bolt backing plates. Both would except the LT1/PBR system. Since the LT1 and LS1 systems are entirely different, I'd expect the plates to be dissimilar as well.

JamesC

 

Actually I've had the pic for a long time now & didn't go to the link you psted above, so I didn't realize that is where it came from.

 

Cool. Like I mentioned, I hope it's been somehow helpful. Glad I'm not the only one who occasionally loses track of where info came from.

JamesC

 

That's right. The swap is super easy and takes no longer than an afternoon to complete. I just got through with it on my GTA. Unbolting the axle on a 9-bolt is a much less daunting task than it sounds. Undo the four axle bolts, pull out the axle, change the backing plate, and put the axle back in. Requires no special tools, and that part only takes about 10 minutes per side. Just make sure you get all the pieces you'll need beforehand: backing plates, calipers and carriers, rotors, e-brake cables, and brake lines/hoses. You'll need to make sure you get the driver's side soft brake line for an 89-92 car, as your factory disc setup has a hardline straight to the driver's side caliper. When you do the swap, you'll need the rubber line to connect the hardline to the driver's side caliper (and you'll need to either bend the factory hardline a bit, or buy all new hardlines for an 89-92 car). Also, don't forget the proportioning valve, you'll have to either modify the original with a stiffer spring, buy a 1LE valve, or put in an adjustable proportional valve. Otherwise the rear brakes are hardly going to work at all.

-cal30sniper

 

Ok I'm gathing parts for the ls1 brake swap well I just got the calipers I need bracket specs they we

 

Hope I`m not derailing the thread, but I`m about to swap pbr rears onto my 10 bolt drum. I`m aware of the cutting and drilling part on the flange, but I just noticed that the backing plates that came with the PBR`s are from a 9 bolt.

Can i still retrofit a 9 bolt disc plate to a 10 bolt drum flange with some cutting/drilling?

 

With enough cutting, drilling, and welding you can accomplish anything, but it would probably be way easier to just order the correct backing plates from flynbye and get it done right.

-cal30sniper

 

DOT 5 is a silicone based fluid and will always feel spongy. DOT 5.1 is regular brake fluid with a boiling point of 518F.

 

Thanks