I'm just wondering what the REALLY QUICK cars are running for rearends and axles. I've run as quick as 11.56@117.25 with a best 60' of 1.57 on Drag Radials with the 7&5/8 rear.
Unfortunately I'm at the point where my stock axles are snapping every few runs at the sticky tracks although they hold up well when I'm only running in the 1.60's.
Anybody have experience with aftermarket axles in the stock rearend? What about the C-clip eliminators? I drive ALOT on the street and I don't need any leaks. I saw a company called Superior makes upgrade axles that uses the c-clips. Anybody hear anything on them or any other axle manufacturer.
Also,I've found in my experience that good used GM gears hold up well and are pretty quiet even after the beating I lay on them. I think it's because after driving around in relatively stock vehicles they are work hardened. Any comments?

 

All the quick cars run 9" Fords, or an aftermarket variation of the theme. This includes every NASCAR and every Top Fuel car.

I'd go with a good bolt in 9". Use the nodular iron case from MWE or Strange. Go with the Daytona pinion support. Use a good quality gearset and all Timken bearings. Run 35 spline axels. For drag racing I'd say use a spool or a Detroit locker if it ever sees the street.

A 12 bolt will also work, but by the time you add up the costs of a cover girdle, altered tube ends to allow you to run axels without c-clips (I'm not much a fan of c-clip eliminator kits), and all the other stuff it winds up costing the same or more than a 9".

BTW, I think it may be illegal for you to be running c-clips and going that fast.

 

at 10.99 you need aftermarket axles and retention devices (no c-clips). TKO covered the basics. from experience the 12 bolt is a little lighter and faster (unspring weight means a lot in ET's), but a good 9" can last for a long long time.

 

Thanks for the NHRA info PhilM. I wasn't sure when the break point was.

I will offer this additional tidbit too. I read an article where they swapped three rears into a car to see if they made a difference in ET. They used a 9", a 12-bolt, and a Dana 60. All the rears used the same gears, and same style differential. They couldn't come to a conclusion about which one was better. The difference in the results was basically too low to measure (a few hundreths of a second at most, and the car wasn't that consistent throughout the testing, so effectively there was no measurable change from run to run). The 9" is a bit heavier than the 12-bolt, but a Dana 60 is a royal pig! I would have thought it would have slowed the car down measurably, but it didn't.

 

yeah, i remember that story. and there wouldn't be a measureable difference. of course if you wanted to spend big bucks you could get an aluminim housing for the 9 inch...

and let's not forget the ever important argument about keeping your GM vehicle all GM...

 

In my opinion a car like yours which is probrobly no lightweight and has alot of torque would like a 12 Bolt.I have a similar situation(heavy weight and tons of torque)and havent had a problem with mine, after 2 years and several hundred runs plus many thousands of street miles.My best times with the car on pumpgas is 11.46@115.81 w/1.55 60ft and my 60ft's are usually in the 1.55-1.57 range.Last year I spent most of my time running racegas and my best is 10.69@125.80 w/1.47 60ft and consistant 1.47-1.49 60fts.

I ordered mine from Moser with 3.08 gears, Eaton posi, 33 spline axles, big ford housing ends, and the alum cover.Total was $2280 plus shipping.I am currently switching over to 3.42 gears to help further lower my 60ft.

If you want to stay with a production rear the only one I can think of is the aussie 9 bolt used in many GTA's and the 1989 TTA. It has a 7 3/4" ring gear and is slightly heavier duty all around but parts are expensive.Though it does help that 3.27 gear is probrobly the most common version.I know of several TTA's that are in the 1.5's with them,best I've ever heard of is a 1.56 60ft.The fastest I've ever went on one was 11.99@113 w/1.63 60ft in a stock TTA.But at that point I still think your pushing the strength of the rear and should really upgrade to a beefier rear.

HTH,
Steve

 

Even though it means spending a good bit of money, with your application, you definitely need to upgrade to a beefier rear. You could go with the moser bolt-in 12 bolt unit with a c-clip eliminator kit or a ford 9 inch. Either way, a stock 7.5" rear has no place under a car running those times and that much horsepower, even with aftermarket axles, it's still too weak to live very long.

 

real car guys just run the best part they can, regardless of the name of the company who was put on it.

lets put it this way, if there was any advantage to running a 12bolt or other rear, top cars in drag racing and NASCAR would use them... but they all use 9"...

if it makes you feel any better about it, it doesnt have a single ford part on it... its all aftermarket.

 

Actually those cars don't have a choice. They have to run a Ford 9" by the rulebook. No other rear is even allowed. That says volumes in and of itself.

 

guys, the GM thing was a joke, I have no problems using other stuff...chill out.

 

I run a Moser 9" with 31 spline aluminum axels. Hasn't given me a problem yet, save for a blown pinion seal.

 

Every part has advantages and disadvatages. For most cars I think the 8.875" 12 Bolt, 8.5" 10 Bolt, and 8.8" Ford rears are more than adequate. Each of these rears is lighter than, and requires less power to turn than the Ford 9". All of them can be set up with big Ford ends so there's no c-clips. And I know each of them can easily handle a mid 9 second car(3500lbs), and I know several that are in the mid to high 8's with excellent reliability.

I mean by your logic everybody should be running a TH400/4L80E trans but instead people generally run the weaker TH350/700R4. Why? Because most of the cars dont make enough power to break them, and you'd be giving up power and have added weight if you went TH400.

Just because everybody uses something, doesnt mean it's the best for your particular application.

Steve

 

Well, if you wanna cough up the cash the strange aluminum centersection for the ford is lighter, and moves the pinion gear 3/4" up on the ring gear so it requires less horsepower to turn. Either way, use the ford housing ends, the c-clip eliminators use VERY small bearings. easier to swap gears in a 9" IMO too. I already have a 3.90 and 4.10 gearset centersections from previous cars, i can easily swap the 4.10s with the locker out for the 3.90 posi after the weekend is over.

 

I am scared I am going to blow my rear end up. My car has ran a 7.82 @90.4 in the 1/8 on pep boy tires with a 1.84 60ft., with no SFC's, LCA's or brackets in a t top car. After my suspension mods I hope to be cutting a low 1.7x atleast with the pep boy tires(maybe I am hoping to much) If I can drop my 60 a few tenths, I can drop my total ET buy atleast that or more. I hope to be around 7.'5's after some suspension work and a little carb tuning, my friend thinks I will go faster but only track times will tell for sure, Heck, everyone was shocked when my car ran what it did. I can't afford a aftermarket rear, I have welded the tubes and put on a girdle. On the car not me. I am really scared to put a set of ET streets on it. The car can leave harder but it wheel hops so bad the rear view mirrow came off and hit me in the head at the track resulting in my almost hitting the wall. Yeah I wasn't happy. Later on this spring I am considering a cam/stall swap and hope, and I mean hope to be running bottom 11's, and that really makes me worried doing that with a stock rear. I just don't want a axle to come out at about 90mph.
Right now the car spins so bad it never really hooks up hard to put enough stress on the rear. We'll see how long it goes.

 

U really should have built your car from the bottom up. Doing the engine last seems like it would save you guys from a lot of grief....

 

Well, a lot of us don't "build" the car at all, when we replace the stock 305 that we blow up we go ahead and build the motor we want, thus keeping the car on the road, then of course we build the tranny after that goes, or at least when the one that's in the car shows signs of dying, i.e. loosing gears.

LilJayV10, at least get some c-clip eliminators, at least then if you break an axle, it won't come flying out. If you do the suspension mods, you car will hook better, even on the cheap tires, probably resulting in a broken axle, i'd go with the eliminators, at a minimum.

 

I personally want to get the Moser housing and axles, and a ebay thirdmember.

Of course, I am a cheap bastard.

 

i agree 100%..... but..... look at his post.

he asked, "what are the quick cars running?"

thats what they're running. a lil overkill? for a 400hp street car, perhaps.. for a slick tired 500ish hp car that you want to still be able to drive everyday, its not bad insurance.


yes on the 12 bolt, ive seen the 10bolt break, i dont personally know anyone on the 8.8" ford.
if your car came stock with it, keep it... if you can get a bolt in one cheap, do so.... if you have to pay out the nose for one anyway, you might as well get the 9" so that you get the drop out centersection... but like you said, its give and take anyway.
really, with 3rdgens, your only strong choices are aftermarket 12bolt, 9" or the ultra rare dana44.


YES!!! they should!

then again, i kinda like it when my parts dont break... ive gone thru several 700R4s behind my 400... when i put the 400 (now blown) in my daily driver convertible this summer, i DONT want to blow another one up... im swapping to a t56, but same concept...

if you want to mod the car, and are relying on it still to get you around, you are stupid to NOT beef up the rest of the drivetrain to the point of slight overkill...... the fastest for racing? no... but racers break parts..
you dont want to break parts, you get bigger, heavier parts..... go only slightly slower, but you dotn worry about breaking parts.

 

Damn cheap *** rearends, what in the hell was GM thinking? Ahhh lets see, lets put the same rearend in our performance cars as we do our S10 trucks, then then we go to a LT1 engine with a 6 speed(new technology mind you) but lets keep the same junk rearend even though more tourqe and the 6speed will probably frag a rearend quicker but don't worry about it. THEN THEN lets put the most technology advanced pushrod motor in our performance cars LS1 with a 6 speed but keep the rearend we put in our S10's. OK, now I am not the smartest guy in the world, I know that, have accepted it and am dealing with it on a day to day basis, HOWEVER when did this seem like a good idea? F body's would be the perfect car to build if the rearends were as strong as the mustangs, well and maybe dual exhuast would be nice too, but I'd take the strong rearend over the exhaust any day of the week. CRAP!!

 

What are you talking about? I haven't heard that setup before.

 

The thing I never understood was how they couldn't be awash with warranty claims for blown rear ends. The only thing I can figure is that with stock tires the car doesn't have enough traction and just lights the tires up before it puts enough stress on the rear to break it.

It really i stupid that they kept the same rear from '82-'02. The only thing they chnages was going from 26 to 28 spline axels. Mustangs have 28s stock and everyone knows that the weak link in the 8.8 is the 28 splien axels, which is why so many people upgrade to 31s. Hell, the '93-'95 Lightenings had 31s stock.

I guess it just didn't pay to do it, which is the only reason most car makers do anything.

 

yup.

the tires usually dont put enough stress thru it to break it.



thats why you see all these guys running nittos and ET streets with blown rears, but you dont see the regular cars blowing them with street tires.. you can frag one with a stock 3rdgen if you put slicks on.


matter of fact, 2 weekends ago, a good friend of mine blew his rear apart on his 2000 camaro... on only the 2nd run with ET streets. and he has a auto.



thats why i have regular tires on my car... im not putting the sticky ones on until i get my 9" in...

 

:werd:

 

man...I was going to buy Goodyear Eagle F1 tires but now I am afraid....

 

I will agree with you there TKO. I did read an article when the LS1 cars came about that said GM claimed the clutch would go in these cars before the rear...interesting.

 

I guess when I said there are 9 and even some 8 second cars running these rears(the 12 Bolt and 8.5" 10 Bolt)you dont consider them quick.He's in the mid 11's which is extreamly respectable but does not require a 9" Ford rear.Require is the key word here.

I havent had a problem with the 12 Bolt in my slick tired 500+WHP(650hp at the motor) 3500lb car. And I dont go out to break parts, as I drive it on an almost daily basis from April-Nov including drive it to the track.Last year alone I made over 200 10 second passes with 60fts in the 1.47-1.49 range.My 1/8th is 6.79@between 100-102mph.Thats reliable in my opinion, and will last him many years at his performance level and beyond.

I'm not saying he shouldnt consider the 9" as an option, some people make it seem like it's the only choice.IMHO the only time a 9" Ford should be considered mandatory,as your making it out to be,is on 8.90 and quicker cars.Slower than that they all seem to hold up well when properly maintaned.

Steve

 

I guess I should have been more specific in my questions. I wanted to get some input from people who have ACTUALLY changed components in either their stock rears or exchanged rears to the, without question superior, 9" or 12 Bolt because they were having trouble keeping their original rear together.
My problem stems from the fact that I've had the car for 8 years with the 455" in it and I don't know how much longer I'll be keeping it. Maybe another year or so.
Back to the beginning. When I first built the car I decided to see how long the rear would last. I figured, like most people would think, that it wouldn't last long and then I'd upgrade.
I was suprised by the gaff it would take. From day 1 it ran in the 12's and now runs in the 11's regularly. My first set of 3.73's only lasted 1 year, but since I started only using used GM gears they have been holding up well. I replaced the posi after a year or so with an Auburn Pro and that works great. The axles were the most suprising part because they lasted about six years(hundreds of runs). The car isn't much faster now but when the car nears a sticky track I get nervous.
That's the crux of the problem. Had the axles snapped early on I would have stepped up to the better rear immediately.
Now it's water under the bridge and I don't know if I can justify the expense for what might be only another year.
From my experience I would say to anybody planning on running well into the 12's or faster with sticky tires and <1.7 60' times and doing it regularly(bracket racing) or for any extended period of time(years) I'd step up to one of the big rears.
Conversely, if I was running any type of regular street tire(even the expensive high performance tires) or had sticky tires on but was only doing >1.7 sec 60' times and wasn't planning on going faster or racing weekly I wouldn't worry about up-grading. If you're breaking parts under these situations you're doing too many donuts in the parking lot of the 7-11.

Finally, check this out. My axle snapped .1 second after the picture was taken.

http://davemilcarek.com/110803/pages/11-8-R2%20052.htm

 

For a 9". The moser 9" housing and axels is the only things that are different than a standard 9".

I called up Moser about 1-2 weeks ago and talked to a tech, and he said its easily doable.

 

i think the main problem with the rears is if you have a standard. i know a guy running low 11's with a posi in his 80 malibu 7.5 rear with slicks. im not sure if the older 7.5 rears are stronger but this one held up to his 400. but the thing is his car is automatic. the automatic cars take up the slack in the drivetrain. unlike standard cars the snap of the clutch is more violent than an automatic take off. if you have a 5-speed jack one side up leave it in 1st and try turning the wheel back and forth. youll get alot of slack and when you take off all that slack is very quickly being taken up and which IMO snapps the rear ends quick. my brother has a 400 with a 5-speed and had a 4.11 posi unit. and he broke it on the 6th pass down the track with slicks. he only ran a 13.30 @106mph(i think his car has some issues, i think it should be faster)

 

I agree with this, and also a standard trans puts a beating on the gears on every shift too.Where as an auto keeps the gears loaded under acceleration.

Steve

 

I agree with you as well on that. standard cars just throw the hammer down on the rear end. it is common sence but i know ill get someone on here to argue with me. thats why when you do high RPM launches with the 5-speeds and slicks they often bust. because take up all that slack is either gonna brake the rear or brake the tranny.or if your lucky, nothing will brake lol just my opinion i guess.......i think im going to go with a 9 bolt because its stronger than the 10 bolts. and i dont think ill be hammering on my car a whole ton but no idea. i think the 9 bolt would be sufficient but not for anyone going very high hp. just my .02

 

A little news flash for you Top Fuel cars have used 12" rears for about nine years now and before that it was a 10.5 rear.

Jerry

 

That's true, but the design is exactly the same as a 9", just with a bigger ring gear to allow the gearsets to live under these conditions.

 

If you want the truth a 12 bolt and a 9in are about equal. It takes 20 minutes to change the center section in a 9 thats why thier so popular. I ran a 14 bolt rear in the truck when I had the BB, makes a 12 or a 9 look like a toy.

 

Yeah, well a 10.5" ring gear will do that. 'Course it also weighs as much as an all iron small block!

 

if your running 11s and only braking axles then upgrade to the moser axles there stronger

 

The only problem with that approach is that it will shift the weak link inside the rear to the gearset. A broken axel sucks, but it's easily repaired. A blown ring and pinion means a lot of time and money to fix. If you're breaking stuff you need to upgrade to a rear that can take the power and traction you have to throw at it. Especially if you're bracket racing and trying for that trophy or to win some cash. You can't afford a car that isn't reliable.

 

Well, there's something to be said for doing it yourself. Not necessarily to save $, but to have someone to blame if it leaks etc. Even if you have a local shoppe do the install & shimming of the parts, it's better than having to ship something back to Moser.


As far as 9" vs. 12 bolt: I don't think I would get excited about changing centre sections all the time so the easy-change aspect of the Ford 9" doesn't do much for me. The extra drag by the 9" isn't enough to be measurably different in e.t. a lot of times. I just like the iron centre section of the 12 bolt housing vs. the fabricated steel of the Ford 9" but call me weird.

 

You have to understand that cheap ****s in business exist everywhere. Car manufacturers, and hence dealer will screw you. They keep a thin flask of vaseline in their coat pockets at all time. Your bung isn't safe and neither is mine.

When someone brings in a warranty item, it'll be covered, or it won't. If it's within mileage range, we go onto step two. If it's a wear item, but way within limits for mileage, we go onto step three. If the owner is a non confrontational person and they tell them it's "normal wear but we can put a new findangle item for 1200$" then it's not warrantied; they have them fix it or take it elsewhere to get it done for 900$. In place of "normal wear; no warranty" commentary, they may accuse the owner of abusing the car and trying to not warranty the clutch / rear / whatever.

When you know they will try & screw you over on the rear in your 1999 TransAm with 18k on it and 2 years olde, will you go there? Sure. What if you're going to be driving the car harder in the future? You might just say screw it and install a 12 bolt. You (if you're a fairy like most people,) might back off the warranty issue and have Daves repair shoppe fix it for 390$ w/ a new gearset and labor because your warranty has a deductible.

Bottom Line Section 1, Subsection A: People and Businesses will screw you over when they can. If you let them, then their continuance of trying to screw you is YOUR FAULT.

Bottom Line Section 1, Subsection B: A Business will spend 28.9 million refuting warranty claims on 94-02 rear differential when an additional 7.9 million would have gotten an 8.5" differential in that run of cars in place of the 7.5" diff. Why? Because Joe Schmoe wanted a raise and convinced his bean counter cohorts that the new 1982 Camaros and Firebird line up would save money by going to the smaller differential. Joe got his raise for saving the company money (on paper; reality says otherwise) and your car got a differential that is good, but not good enough to be considered better than a "fuse" in the applications in which it's installed.

-Matthew

 

I believe this too. Thank G0D I've got a 12 bolt in my standard car!