My '91 s10

most hydro e-brake setups I've seen involve running a 2nd caliper setup on the rear.   I think you could get away with just using a single piston setup though so maybe you could take your stock front brakes and add them on the rear.

Doesn't need to be that complicated. Run your e-brake in-line in the rear line... easy peazy.

Doesn't need to be that complicated. Run your e-brake in-line in the rear line... easy peazy.

exactly my plans.

Finally got back out to the shop tonight, pulled the coilovers again and got the front of the frame painted up for good finally. Not sure if I'll clear coat it, probably not.


also started work on my ZR2 8.5 rearend.




Help! How can I shorten this rearend about 3" per side? I'll do some searching but input is greatly appreciated. Can these axles be re-splined or will I need new axles?




I'm gonna clean up the other axle tube, then maybe get the pumpkin sandblasted or just keep at it with a wire wheel.

Frame looks great.  A friend of mine shortened a ZR2 axle but I don't remember the details.  All I remember is that he spent more money on it than he had planned to! 

Is that a G80 diff?  I just had a thought about those - can you shorten or completely cut off that swinging weight in the carrier that unlocks the diff higher speeds?

Axle should be hardened, so it won't be the easiest thing to cut.  Also looks like the splined section may have a larger diameter than where you would want to be resplining.  If that is the case then it won't work.

From what I have picked up from some of my friends buying new axles to spec is the way they go.  Had one of them mention that most GM axle shafts aren't balanced too well and getting new axles to spec will make things smoother.  Most of that is shop talk, so take it as you will.  I've got a pair of 8.5 rears that I'd like to put under my 1st gen at some point, but both could use different length axle shafts to work, so I was planning on pricing out new shafts from moser and the like.

Is that a G80 diff?  I just had a thought about those - can you shorten or completely cut off that swinging weight in the carrier that unlocks the diff higher speeds?

I have no idea, but you're welcome to buy it and find out! haha

Harley, thanks for the insight. I had a feeling I'd be getting aftermarket axles, no big deal. Good time to switch to 5x4.5 too, been thinking about it.

5x4.5? Why a Ford/Jeep pattern? If that's the case & you want to run Ford/Jeep wheels why didn't you grab an Explorers' 8.8? It is waaaaay stronger than that 8.5 AND it doesn't use a garbage posi, such as the Gov-bomb.
I also don't see the reasoning behind wanting to shorten a ZR2 rear, too. It's only 3" wider per side than a standard 2wd rear axle. Would be fine if you plan on using Vette wheels... but then I see you want a Ford/Jeep pattern. If it's a typo I hope you know the proper bolt pattern needed (standard..) is 5x4.75. I'd hate for you to order axles for the 5x4.5 & waste money if it's something stupid like that.

90% of imports use 5x114.3, which is 4.5". The selection of wheels is endless compared to 120.65/4.75, except BMW wheels which are almost always narrow with stupid offsets.

I don't plan on using vette wheels at all, they have little to no dish which is high up on my want list.

I'm mainly using this 8.5 because I have it. I definitely won't be using the stock carrier. I'm going to price out a built 9" before I spend any money on this 8.5, but cleaning it up keeps me out of trouble for now atleast. I'd like to stay GM but 12bolts are pretty hard to find affordable.

Sorry if that came out sounding rude, just clearing it up.

Not rude at all. An Explorer 8.8 is almost exactly the same as a GM 12 bolt. Why do you think there was court cases filed by GM against FoMoCo over it? 8.8 uses the same pinion bearing among other parts from/for the 12 bolt housing. 8.8 can handle about the same HP as a 9" for 1/2 the price! all you need is a rear girdle & you're good to 600+ HP. Plus it bolts right in place of the stock S10 rear.. why do you think I chose it behind a 580 +/- HP big block? Have you ever read my build? Project1953

..brake lines are the same. Just use an Explorers' Tee to the rear lines. Drive shaft.. maybe you need one made up OR maybe you can get lucky & find one that's stock (ford or GM) that fits. I found a Ford shaft & put a GM yoke on it.. 1350 U-joints, too.

I don't give a rat's ass about "bolting in" this time around, haha. I've already chopped the leaf mounts off the 8.5. I'll look into the 8.8 some more, It has the offset pinion aswell, correct? I know it doesn't matter but for some reason I don't like the idea, partially for 4link tab purposes. Some exploders came with disks, do you know what size rotors/calipers off hand?

97-up all had discs.. 11.5" rotor. DIH parking brake. No venting. The rotors weigh just about nothing compared to S10 Blazer rear discs & C5/C6 rear discs.

i agree the 4.5 pattern is a wide range, and mustang wheels are cheap and sizes are as good as vettes.

personally i'd recomend just running an explorer 8.8 if you plan on ditching the 8.5
redrilling a hub is very simple to do if you do keep the 8.5, or aftermarket axles will allow the use of any pattern too.

I also recommend getting the exact bolt pattern you want.  BMW's bolt pattern is very similar, but not exactly the same as the GM pattern.  I don't know about the import wheels, but the same goes. If you want a pattern measured in mm I suggest getting that pattern exactly rather than the closest pattern in inches.  Same goes vice versa.  It may not happen to you, but I've read some horror stories using BMW rims on S trucks.[/engineer]

You're saying the explorer rear rotors aren't vented? Isn't that bad news when on the track?

Ford's 5x4.5 converts exactly over to the common import 5x114.3mm, unline the 5x4.75 chevy to 120mm BMW. 4.75 is actually 120.65, which is .65mm larger than BMW/Audi etc.

Ignoring all other rear ends, roughly what will my 8.5 hold up to with moser axles, aluminum diff cover, eaton/detroit carrier, 3.73 gears, etc? Need to justify an 8.8, help!

I can't tell you if a vented disc is better than a non vented disc but I can tell you any disc is better than a drum & it won't have almost instant fade.

If it really bothers you.. go find some slotted & crossdrilled rears.

If it really bothers you.. go find some slotted & crossdrilled rears.

that's totally different from vented,
and yes, vented would be nice on track.
most track guys run solid vented rotors. quality slot/crossdrilled are out of my price range, and the cheapo ones are dangerous.

The 8.5 is going to be unpredictable as to how much hp it can withstand. But even upgraded it will not stand as much as a stock 8.8 will.