hi guys did third gens (camaros specifically) come with different rears? for instance, i know all 4th gens got the pos 10 bolt (7.5"), and i thought 3rd gens got the same, but from what i see, thats not the case. from various posts ive seen, some say they got the 10 bolt (which i suppose is the same as the 4th gens) (NOT the 8.5" as the GN's), and others say they have a 9 bolt (NOT ford 9"). are there any others? what did 91-92 z's come with? is the 9 bolt stronger than the 10 bolt? did one or the other only come with posi, or both, or was it an option on both? im looking to get a 91-92 z and "build" it , and im kinda confused by this for instance: which rear did 305 cars get? which rear did 350 cars get? gearing?

and, on another note, i owned 2 4th gens, both t-top cars. never had any leaking issues (unless driven through car wash). yet i see lots of posts about people complaining about leaky ttops on 3rd gens?? is it just cause the cars are older (something new weatherstripping could fix), or is it cause the cars themselves are less rigid? would the power of lets say a "decently" built 400 sbc (or even 454 bbc), be "too much" for a t-top car? ( car would have sfc's of course, but theres only so much they can account for).personally, i love t-tops. but, if things go as planned (lets say soemwhere in the neighborhood of 500 hp and 500 ib/ft tq,(flywheel) give or take a bit), would a hardtop car be the way to go?

any and all opinions welcome and thank you

 

9 bolts were the hi perf option on mid-late 80's third gens. 10 bolts used before 85 or so are very weak, later models are better, but not as strong as the 9 bolt. 9 bolts came in Camaros and Firebirds, like the one under my 89 Formula 350.

http://9bolt.com/

 

9-bolt: Made in Australia and consequently hard to find parts for....available from 1985-'89 in HO&TPI cars, and TTA's.....factory ratios of 2.77, 3.27, 3.45, and 3.70 (most autos were 2.77, most sticks were 3.27).....substantially stronger than a 10-bolt.......had TERRRIBLE Delco-Moiraine disc brakes until '89 (find an '89 PBR rear or plan on a brake upgrade)....most were posi/disc but some open/drum rears were made

 

The later cars got 28 spline axles in the 10 bolts (90 and up as I remember) which they still use in the 4th gens. The 3rd gen axle is about 2 inches narrower than the 4th gen rear ends.

My T-tops have dripped on occasion on my 2002 Z-28, they just do that....(generally speaking)

 

to add to the borg discussion, ther is also a 3.08 ratio also i recently found out. i have seen 2 of them in the memphis area. im for sure on this as borg gears are stamped with borg warner and the ratio.
there is a replacement T -top seal kit for the third gens based off the 4th gen design called "gen 2". they have drain holes where the top seal meets the body seal. the GM PN for this kit is 10164133.
a friend replaced his kit and was quite impressed vs the orig style kit.

 

thanks for the info so, to sum it up, would it be worth it to swap a 9 bolt in a 91-92 camaro? or would the cost of parts for it and the unavailability of the parts not be worth the hassle? just better off going 9" or 12 bolt then i suppose ? although, i would assume itd be cheaper to purchase a 9bolt out of a 85-89 tpi car, and go that route (if parts cost/availabilty isnt too bad)?

to "Great J": by "pbr rear", what do you mean? panhard bar? and, by "upgrading" the brakes for the 9 bolt, is it only through some 1xxx$ baer brake kit or something like that? or would 4th gen rear discs and calipers be an option?
Thanks

 

The 9 bolt is only slightly stronger (if at all) and the last set of gears I found for them was available in 1 ratio (3.89 or something) and were nearly $400 for the gearset. I'd not swap to one of those axles on purpose. If you have one, run it until it breaks, but I wouldn't install one.

 

9 bolt is MUCH stronger than any 7.xx" 10 bolt. I've run quite a few 1.6x short times and its never made a hint of noise. If I had one of those 10 bolts, it would have been on at least a 2nd rebuild.

Gear sets are expensive though.

 

I dont comprehend why one of the big gear companies like Strange or Richmod doesnt produce parts for 9 bolts. It doesnt make sence to me, as many that came in 3rd gens.

By PBR brakes he means get an 89 if possible because they came with the better PBR brakes. aluminum calipers and I believe 11" rotors. Nice brakes. Unfortunately they only came on the 89's because that was the last year the 9 bolt was used, after that they upgraded the 10 bolt to the better axles and used those.

 

Maybe. I keep thinking "stick cars". There are many 4th gen guys running 1.6's on a 10 bolt, but for every one of those, there are 10 who have rears that failed. So, it may be a little more than just "slightly" stronger, but I'd still not go in search of one or put much money in it (unless it was already in my car).

On a side note, that is a great looking Turbo TA you have (I always wanted one of those).

 

Darth is right....by "PBR rear" I mean a rearend with the PBR aluminum-caliper brakes. They're MUCH better than the '88 down iron calipers, but are hard to come by since they only used them on the 9-bolt for one year.

There are lots of options as far as brake upgrades. I personally plan to mount up a set of 98+ F-body discs on my 9-bolt. From what I've read it isn't a difficult swap but does involve some cutting/drilling, and can be done without breaking the bank. There are also guys who have used '93-'97 brakes which are the same as the 3rd gen 10-bolt PBR brakes, and of course there are the big money options like Baer and Wilwood.

The 9-bolt is substantially stronger than the 10-bolt (run a search for Miles' big-block drag-only 3rd gen that's running strong on a 9-bolt) and even though they're hard to find parts for they're a LOT cheaper than any 9" or 12-bolt you'll come across. So basically....if you need something tougher than a 10-bolt but can't afford to spend $2000+ on a 9" or 12-bolt....the 9-bolt is an EXCELLENT compromise.

 

the borg 9 bolt is rumoerd to be as strong as or stronger than a dana 44.
as for sinding parts miles can be reached at www.diffsoultions.com. hes currently updating his site. there was one fella over at TGO gathering intrest for a 9 bolt girdle. and he had quite a response. ed miller can hook you up with al of the PBR brake stuff if ya want it. go to the brake forum and he has quite a few post so he will be easy to locate. he also has a C-4 conversion for third gens which im looking into this mod myself.

 

9 bolt parts used to be hard to get. Now you can just go to http://www.9bolt.com/
Read the FAQ on how much stronger and better they are to the 10 bolt.

GM did offer one more diff in the third gen. It came in the SLP Firehawks and used to be available in the GMPPC. The diff is a Dana 44. It is a 8.5" ring gear, axles bolt in like the 9 bolt and ford 9".

Quick and easy identification other than counting bolts:
10 bolt = solid rear cover although you won't know if it's a 7 1/2" or the updated 7 5/8". Parts are interchangable
9 bolt = has a rubber fill plug in the rear cover
Dana 44 = Has a metal pipe plug to fill in the rear cover.

To find a mint Dana 44 now or when they were available from GM, you can expect to pay close to what an aftermarket bolt in 12 bolt or 9" is now.

The 10 bolt can be beefed up to take a lot more abuse. I had mine down into the low to mid 11's with 1.6x 60' times before finally swapping in a ford 9" for more ratio options. No matter what you do to try and beef up the 10 bolt the weak link is still the tiny ring and pinion.

 

so 93-97 fbod brakes would be the closest thing to a "bolt on" for the 9 bolt then i assume? theyre good enough for me (and not expensive). your 3rd paragraph pretty much sums up what i was looking to hear i fathom you could probably pick up a 9 bolt from a scrap yard for pretty cheap. or just buy an Iroc, swap rears (if lets say mine has a 10 bolt), and resell iroc yeah, 9" and 12 bolts are quite $$$$, even used.

thanks for the link quickchicken

and btw, Great J, gearsets at 400$ are quite$$$. if im not mistaken , 9" and 12 bolt gearsets are pretty much the same price as 10 bolts.at 400$ a pop you better hope they last.

thanks all and any more opinions are always welcome

 

tell me about it
i had 4.10's on the car in the sig. i managed to snap the gears, on the street, on street tires, in the f**king rain to top it off i nailed it from a stop, and for some reason the car HOOKED (in the rain, i still dont understand how), and snap.

but, no matter which rear i get next time, im probably gonna stick in the 3.XX ratios. i like em better never really grew to like the 4.10's (had em for 2 years). i enjoyed them more after the cam was in (rev limit raised another 1k), but still wouldve prefferred 3.73's or even 3.42's.

is the Dana 44 8.5" rear the same as the GN's? or is that another animal all together?
thanks