8.5 in rearend

Built6spdMCSS said:

Buy him dinner first see where it goes..

See the loose clamp and the Muffler rotated? The pipe is unbolted.

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Somehow I was able to see the disconnected pipe and where it attached but still thought... Ya know what? I don't know what I thought. I guess I had a "moment". Although 'Warlock' mufflers exist.

doood said:

This is a bolt-on hooker kit that came with the Holly LS swap kit for g-body. It has been nothing but trouble. Parts were made wrong, slip fits weren't round, terrible drone at 70mph, won't hold its alignment under its own weight when clamped. If I had known better, I would have a local shop build the exhaust. The one good thing is I can take it apart. I wasted about 30 minutes trying to fish a bolt out of a UCA before I finally relented and moved the muffler out of the way to poke the bolt out with a screwdriver. That muffler is not what came with the kit. That's a thrush muffler that's quite subdued for a 'turbo style'.

spidereyes455 10-4 on the locktight.

I'll likely get the rear installed tomorrow and then I'll be measuring the drive shaft running length. If I recall correctly the way to do this is to put the yoke all the way jammed up into the trans, and measure the distance between the center of the front u-joint and the center of the differential yoke u-joint center.... minus 1 inch.

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Sorry for the dumb question, sometimes you can look at a picture and know it should make sense but it doesn't. I was unsure if you had the ability to uncap only one muffler for some reason, or if you did indeed have multiple tailpipes mounted in a custom way. From this angle it appears possible that the tailpipe is connected loosely to a second outlet on that muffler (allowed to rotate), and the other is off. I don't know what others do to their cars and I only glanced at the photo before commenting. I've made more than one system from scratch and have encountered the same issues you mention, and it's for those reasons that I don't trust a shop to do them. I was also extremely underwhelmed by the Thrush Turbo mufflers, Raptors are louder but still too quiet, and Lawson sounds good but everyone keeps sending me the Jones Full Boar copies since they use the same part #.

As for driveshaft measurement: I've seen numerous ways to do it so I'd check with whoever you're having make yours.

I definitely don't need the UCA to LCA brace. My friend has a very fast Monte with a Ford 9-in and is using stock LCA mount...

doood said:

I definitely don't need the UCA to LCA brace. My friend has a very fast Monte with a Ford 9-in and is using stock LCA mount...

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That doesn't mean things aren't moving.

My '84 Monte Carlo now identifies as Grand National!

What a chore. First of 4 bolts to control arm went in like butter. Second was like meh. Third made me think I had talent. Fourth had me wondering if I was gonna finish tonight.

That’s been my experience too. And not only with malibus my 70 was just as bad. Last arm did not line up to save my life.

Triangulated 4 links are fun to get all the bolts lined up 🤣 Good job!

This is incredible. I thought the old 7.5" I had built at the transmission shop in 2021 was going to be a good spare to have around. It has a 3.55 ratio and an Eaton clutch POSI, 26 spline. Well I don't recognize that big pinion nut... that's not supposed to be on there. That's not what came with the kit. Also it has no pinion bearing preload (spins freely), and obviously has way way too much backlash just based on me jiggling it with my wrist. Buyer beware. Just because it didn't blow up doesn't mean it wasn't about to. I'm glad I put the 8.5 in. At 500 miles I'll change the fluid on the 8.5 and check the preload and make sure it's still good. Incredible. I wonder if I broke it doing burnouts or if the guy that put it together is a hack. I probably ruined it doing burnouts.

My guess is both actually. Most guys at shops are mechanics, and not technicians. They replace parts, not follow procedures and diagnostics. Hence why many go by how many ugha dugga's, instead of using a torque wrench. That and a 7.5" doesn't like abuse. I've killed many of them.

7.5 and 8.5 will fail the same way, the Pinion comes loose and from there it's wrecked. Seen quite a few like that in the GM 1/2 ton trucks. 7.5 will fail much sooner, just won't take the abuse as mentioned. I've had my fun with them.

400whp LT1 in my 1995 Z28 took the stock 3.42's for a run





Upgraded to 3.73's and an Auburn Diff. 500whp LS Engine this time with a 1.55 60ft on the prevoius pass. Dropped tire pressures 1psi and firmed up the Coil Overs by one click..





9" and T56 went in after that. Then broke the car.