A question for those of you that have a 3800 S/C... or know something about them (that pretty much covers everybody in the forum)

For the manual transmission with one of these engines, which type did you use?

"the Getrag 284 that came with the 3.4 TDC Engine. It has a non-standard clutch that will need to be adapted to whatever you are upgrading to. It has a designed limit of about 250 ft lb. of Torque and with a lot of care can be used to about 300 Ft. Lbs. of torque."

- from www.americancustomeng.com/which.htm

Is it safe to use this transmission with the 3800 S/C? Has anyone had any problems with it, or used a different one... etc

It's the "with a lot of care" part that worries me...

You have to apply a little generalization here. The same article says the design torque limits of the 282 (5 spd on later GT's) is 200 ft lbs of torque. I know I'm pushing very close to 400, with no problems.

So if the 284 has design limits of 250, it's naturally a stronger trans than what came in the Fiero. Can't see why there would be any concern about the strenght of the 284. The clutch would still be the weakest link.

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Safe? Well GM's ratings obviously say no, right? The 282 is 200 ft-lbs, the 284 is 250-ish. The 3800SC is 280+. Ergo....

So the question is how long will it last being operated outside it's design limits? From people's experience, it seems to be a long time. But when a Getrag dies, you better have your credit line ready. A Getrag 282 is expensive to rebuilt ($1000+ is not uncommon) and 284's are only a replacement item. No parts available. Exchange is $1600-1800. I'd avoid the 284 if at all possible.

Per Jelly's demands that I *SHUT UP*, I removed the following paragraph which can be found quoted further down.

*DELETED* per Jelly's demands.

[This message has been edited by terryk (edited 12-16-2001).]

quote Originally posted by terryk: Safe? Well GM's ratings obviously say no, right? The 282 is 200 ft-lbs, the 284 is 250-ish. The 3800SC is 280+. Ergo.... So the question is how long will it last being operated outside it's design limits? From people's experience, it seems to be a long time. But when a Getrag dies, you better have your credit line ready. A Getrag 282 is expensive to rebuilt ($1000+ is not uncommon) and 284's are only a replacement item. No parts available. Exchange is $1600-1800. I'd avoid the 284 if at all possible. For every 10 Getrag's with a V8 behind it, there is one with the guts on the ground. Use a good one, be reasonably nice and they seem to last a fairly long time. When they become hard to shift, the clock is ticking down....

So you have experience in putting high power motors on these transaxles terryk?

If not, Shut up. California Kid is correct, and check out Archies site.

Where did you get your information on
"For every 10 Getrag's with a V8 behind it, there is one with the guts on the ground."
???

Sounds like your another one with biased facts.
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[This message has been edited by jelly2m8 (edited 12-16-2001).]

What you guy's are forgeting is that these parts are designed with a factor of safety built in. In most cases the factor is 2 so if it's designed for 200 ft-lbs it should be good up to 400 ft-lbs with the factor of safety. At least that is the way we did it when I was in college engineering class.

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[This message has been edited by avengador1 (edited 12-16-2001).]

Show me a Getrag with it's guts on the ground and I'll bet you'll get a confession out of the owner that he abused the hell out of it. The only way that I know of that you can bust one of these up is to consistently pull 5,000 rpm hole shots, with wide sticky tires. If abused on a regular basis, failure will occur just like any other high performance application.

The trans in my car has 120,000 miles on it, of which 30,000 were with the V8. I think that says a lot for the durability of the 282. Frankly, I'm hoping that there becomes a big enough demand for this transmission that GM or someone else decides to do another volume run for replacements/or at least replacement parts.

Just my opinion.

Oooh, tough talk! I like it. I've got these visions of a rooster struting around the hen house.

Actually, you know what. You are right Jelly. Since I've never had experience with a Getrag behind a *V8*, I should shut the *^&% up.

I shouldn't have said they dump their guts. They don't. They tend to just mangle stuff inside but only with the 2.8L V6. Seems the V8's aren't as rough on them.

I will edit that out to avoid further rages.

Now, I will shut up.

[This message has been edited by terryk (edited 12-16-2001).]

Heh, well then...

In which model cars were the 284's in? Obviously the 282 is easier to come by, but I'd rather do something right the first time... if I use the 282 and it dies on me, that's a lot of hassle I don't want to go through...

Anyways, a little background on me... I'm in mechanical engineering at McMaster university right now, so I know or am learning how everything in cars work...

My first car was an '82 Ford EXP convertible. It was a piece of...... then I got an '84 Fiero a few years back, and got hooked. This forum is amazing, there are so many other Fiero addicts to learn from...

Anyways, to make a long story short, I'm going to get an internship somewhere this summer (hoping for a job at GM... fingers crossed) and want a little side project to blow my money on. I want to put a 3800 S/C in a GT, probably... anyone whose ever driven a Bonneville SSEi or Grand Prix GTP know what a good engine it is... all I'm trying to do right now is figure out how to do it right the first time.

Well, that's a lot of typing, to summarize (hehe) I'd like to hear whether anybody's had any problems with their transmissions in... well, anything with a lot of torque, I guess.

Thanks...

I've to date seen exactly ONE busted tranny that was 'over torqued' and it was an older 4-speed. (on a 383 stroker V8, after doing a 'torture test' of constant burnouts for over **30**minuites, the *iintent* here being to break the tranny.)

Nobody else on this fourm of 2500+ fiero owners, very many of them V8 Fiero owners making in the range of 300-500+lf-ft, have come forward with any kind of pictures of blown Getrags. Ever.

That alone is a pretty stellar track record, I'd say use the plain 282, and a GOOD clutch. The clutches are the weak point.

I'm using my plain (110kmile) 282 on this motor:

That's it below, already bolted up and ready to rock (once I get the new clutch for it

That motor makes 295lb-ft, and makes over 200lb/ft from idle to redline.

Best!
Ben.

------------------

Ben Cannon
88 Formula, T-top, Metalic Red           "Every Man Dies, not every man really Lives"
88 Formula, Northstar, Silver                     -Mel Gibson, "Braveheart"

quote Originally posted by artherd: I've to date seen exactly ONE busted tranny that was 'over torqued' and it was an older 4-speed. (on a 383 stroker V8, after doing a 'torture test' of constant burnouts for over **30**minuites, the *iintent* here being to break the tranny.) Nobody else on this fourm of 2500+ fiero owners, very many of them V8 Fiero owners making in the range of 300-500+lf-ft, have come forward with any kind of pictures of blown Getrags. Ever. That alone is a pretty stellar track record, I'd say use the plain 282, and a GOOD clutch. The clutches are the weak point. Best! Ben.

Excellent point Ben,
rock on dude!

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quote Originally posted by BtotheB: Heh, well then... In which model cars were the 284's in? Obviously the 282 is easier to come by, but I'd rather do something right the first time... if I use the 282 and it dies on me, that's a lot of hassle I don't want to go through... Thanks...

If you blow a 284, it'll be a lot MORE hassle. There's also a lot more re-engineering involved, as the 284 mounts differently than the 282. The 284's were in Z34 Luminas, and their contemporary Grand Prix GTP's and Olds Cutlass something-or-others. The transmissions are VERY rare, VERY expensive, IMPOSSIBLE to rebuild (I'm not kidding), and have fewer clutch options available than the 282, which doesn't have very many. The 284 uses a pull-to-release pressure plate. Don't ask me why it uses that, but no aftermarket company makes one; they're only availabe for stock rebuild.

As you can see, I've researched this option.
Take my word for it, go with the 282 and save yourself a lot of trouble.
Better yet, if you're going to abuse the thing, use an Isuzu, have $100 replacements available, and leave the quality transmissions for those of us who aren't doing things that make us worry about breaking them.

I also have a N* swap on the way, BTW.

One little giblet I found interesting about the 284 Getrag and the 3.4 TDC (or DOHC) motor it came with...

Very few of them were 5 speeds. In the years they were introduced, "beta" in 1991 and a few in early 1992, the 5-speeds generated so much more torque that the internal workings of the MOTOR were getting damaged.

I even had a bout with the torque monster as I spun a rod bearing and twisted a crank! Had the entire bottom end rebuilt with forged parts from GM.

Which brings me to the obscure point of interest... When GM put the 3.4 TDC out and mated it to the 284, they immediately STOPPED this motor/tranny combination from reaching mass numbers because of this torque issue. For those individuals that owned these motors and damaged them under warranty, the GM fix was these rare, limited, non-production forged rods and crank.

My blown crank and bearing happened under warranty and was updated by a GM dealership here in Portland to the tune of $3800 and TWELVE WEEKS!!!

Although they never gave me a reason why it took so long, I think it was a combination of the service tech being trained to rework the motor and the production of the replacement parts.

Anyway, the point is, the 284 tranny is vitually bullet-proof!!! Well, the 5-speed is anyway. I can't speak for the automatic. When the tranny holds and the motor bends, I'd say that's a good thing

However, now that I am protected from that every happening again, coupled to the fact that the motor and tranny is now in a car weighing a few thousand pounds LESS...

Did I mention I LOVE my 3.4L TDC?

DKOV -

Oh, I forgot to mention, the weakest link and the BEST part, is the clutch!!! If the torque is going to bust something with this combination, it's the clutch disc... and that's fine by me! It can be replaced

[This message has been edited by DKOV (edited 12-18-2001).]

I've got to jump into this one. I've been running a Getrag 282/Northstar since 1998. I put a lot of miles on this combination. The tranny had 100k on it when I got it and had probelsm shifting into 1st. It still does. And every once in a while the gears grind. Makes an awful racket. But the tranny still delivers.

I considered the advice to use a 284, but after searching for these ellusive beasts, I gave up. They must be related to Sasquatch I think. But I did talk to a lot of V-8 owners who had 282's and I never did find anyone who had destroyed a tranny.

The clutch is a different matter. Almost everyone I talked to had clutch problems at one time or another. I finally got in touch with Gary Zumalt, who recommended the Quartermaster dual disk clutch system. So far this has been bullet proof with a 300 ft/lb N*. I had a centerforce on my 2.8 with nitrous and it slipped. And I'm sure it wasn't cranking out the ft/lbs that the N* does.

And speaking of ft/lbs, this is all a function of load. When you run through the numbers you'll see that torque moves the car at a given acceleration (change in speed). So essentially if you drive the car reasonably, i.e. like the same speed as the 2.8, then no more torque is applied through the drive train. It's not like these engines are cranking out 400 ft/lbs under all conditions, but basically only at WOT. And the Fiero chassis will only allow so much torque to be put to the ground, and then the tires spin. Self limiting.

Will had a good suggestion. I have another. Grab up all the FWD Getrags you can. They are cheap like 100 to $250 at most salvage yards, they are plentiful, and it only takes about $150 to convert one to RWD which you only have to spend once. They can be easily rebuilt. If you happen upon one from a Quad 4, the bell housing will not bolt up to the V-8...but, there will probably be a usable bellhousing on your old Getrag. Swap them. Never throw out an old Getrag without first taking off the bellhousing.

ok my question is about half shafts.
I know some of the high hp grand prix gtp's have problems with snapping them. what are you V8 guys doing to keep from snapping them??

quote Originally posted by aleroboy: ok my question is about half shafts. I know some of the high hp grand prix gtp's have problems with snapping them. what are you V8 guys doing to keep from snapping them??

I'm using Mark Williams Racing shafts, high alloy heat treated. Factory grade steel twisted and sheared in my case. CV's the next weakest link, but not major problem at this time.

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quote Originally posted by California Kid: I'm using Mark Williams Racing shafts, high alloy heat treated. [/B]

cool!
is there a site or somthing I can buy these from?

quote Originally posted by aleroboy: cool! is there a site or somthing I can buy these from?

The web site is:
http://www.markwilliams.com

Parts aren't cheap, $700 for just the pair of splined axles, no CV's included.

I'm running Gary Zumalt Axles. Left side is 2" shorter, right side is 2" longer. Made from 4340 and heat treated to Rc50 behind a N*. No problems at all with the axles. However, these aren't reproducable since Zumalt quite the business. Suspect a set would cost about $500.

Now, as an alternative. As I found out from my local CV joint rebuilder, all the inner CV joint tranny spines are the same. The inner CV joint from the larger GM cars will fit nicely into the Fiero manual trannies. The outer CV joint and shaft can then be changed to the larger bearing size with the 5 x 115 bolt pattern. This necessitates changing to the larger spindle, but the early 90's Citation spindle is a drop in for the Fiero. Get the one with disk brakes. I don't know the axles types but the CV joint guy said he has plenty of stock axles from all kinds of cars and he is sure that one of them will fit each side. If not, you can have a special axle made for about $200/side. It won't be a super racing axle, but at almost twice the crossection of the stock Fiero axle it should be more than adequate. This will then get you larger bearings, CV joints and shafts. Anyone know what cars might interchange with the Fiero lengths? We found something for my long side but the short side may have to be custom.

Couple of things:

1) Check this out: http://discussions.gmforums.com/showthread.php?s=&threadid=10555 (282 vs 284 info)

2) Celebrity, not Citation. The A-body hub carriers are the bolt in swap: Chevy Celebrity, Pontiac 6000, Olds Cutlass Ciera(?), Buick Century. There may also be some Cadillac brakes which allow the retention of the parking brake and may even be lighter than the A-body hardware.
C-body hub carriers may also be workable, but more involved as the C-bodes used a more conventional tapered shank ball joint. C-body hub carriers should allow 1-2 more inches of wheel backspacing. It might be possible to run a 17x11 wheel without it sticking out ridiculously far.

3) What on earth has an axle that's two inches longer than the Fiero long axle?

4) With a Beretta intermediate shaft, the left Fiero axle can be used , along with the shaft from the right axle of a 4T60E equipped W-body. The inner CV joint will have to be swapped from male spline to female spline, and the outer joint will have to be swapped from W-body style to A-body style. I'm not sure if the swap does anything, but I think it's cool.

quote Originally posted by Will: With a Beretta intermediate shaft, the left Fiero axle can be used , along with the shaft from the right axle of a 4T60E equipped W-body. The inner CV joint will have to be swapped from male spline to female spline, and the outer joint will have to be swapped from W-body style to A-body style. I'm not sure if the swap does anything, but I think it's cool.

Does anybody know if the beretta shaft would be strong enough?
I'd like to have equal length half shafts on the car but I also need somthing that can hold the power.

Hi Tom, I thought your swap had the motor/tranny moved 2" over? If so, then how'd you bung up stock axels?

Thinking about a set of Mark Williams axels myself since I'm going to at least have custom splined ends/outter-CVs put on my N* car, and $700 isn't so bad compared to pol-vaulting at 140mph when an axel explodes...

Best!
Ben

quote Originally posted by California Kid: [QUOTE]Originally posted by aleroboy: [b]ok my question is about half shafts. I know some of the high hp grand prix gtp's have problems with snapping them. what are you V8 guys doing to keep from snapping them??

I'm using Mark Williams Racing shafts, high alloy heat treated. Factory grade steel twisted and sheared in my case. CV's the next weakest link, but not major problem at this time.

[/B][/QUOTE]

------------------

Ben Cannon
88 Formula, T-top, Metalic Red           "Every Man Dies, not every man really Lives"
88 Formula, Northstar, Silver                     -Mel Gibson, "Braveheart"

PS: To anyone serious about the performance of their Getrag, I would *highly* recomend Rodney Dickman's add-on rooler differential support bearings.

They're an extra set of true rooler needle bearings you press in (WITH A HAMMER! to the tranny where the axel seals went.

The stock getrag's outter support bearings are just the slip-in oil-type sleeve jobs. Good when new, but when worn even a tiny fraction?

They come with a better, integral, replaceable, seal.

Best!
Ben.

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Ben Cannon
88 Formula, T-top, Metalic Red           "Every Man Dies, not every man really Lives"
88 Formula, Northstar, Silver                     -Mel Gibson, "Braveheart"

What Ben said, and make sure to use a sealer when pressing it in, or it will leak.

quote Originally posted by artherd: The stock getrag's outter support bearings are just the slip-in oil-type sleeve jobs. Good when new, but when worn even a tiny fraction? Best! Ben.

What in the world are you talking about?

The Getrag differential side bearings are tapered rollers--Timken units from the factory, even--that require a $700 toolset to set the preload correctly.

quote Originally posted by Will: What in the world are you talking about? The Getrag differential side bearings are tapered rollers--Timken units from the factory, even--that require a $700 toolset to set the preload correctly.

Ben wasn't talking about the differential bearings!!!! He was referring to the, for lack of better word, "pilot" bronse bushings that are located at each end of the trans case where the half-shaft goes in on each side.

quote Originally posted by California Kid: What Ben said, and make sure to use a sealer when pressing it in, or it will leak.

Let's say you have a low mileage Getrag with a set of these bearings installed that's leaking where the bearing meets the case. How would you go about removing, replacing, or fixing the problem?

quote Originally posted by artherd: Hi Tom, I thought your swap had the motor/tranny moved 2" over? If so, then how'd you bung up stock axles? Best! Ben

Trans movement is approx. 2", do know the exact dimension off the top of my head. The first (short side) axle "whip out" was the result of me acting like a teenager and doing a number of 5 grand hole shots on dry pavement with big sticky Comp T/A's. When it did fail, I was just taking off slowly from a light. The shaft failed at interface to inner CV joint. This was a Mark Williams shaft, but keep in mind that it had 20,000 very hard miles, and that the trans "pilot bushings" in the trans are original with about 110,000 miles on them. As I was in a hurry to get it fixed, I had a local shop shorten a stock axle, used existing CV's, and got it back on the road.

The second failure (with stock shortened) occurred after 5,000 miles, left inner CV joint exploded, shaft was twisted and bent. Again, this one failed on light startup from light. This time we installed replacement Mark Williams shaft and new CV's on each end of left shaft. That was 12,000 miles ago. Will replace pilot bushings with needle bearings on next clutch job (probably this coming season, it's still holding great).

I haven't failed any part of the half shaft on the right side. I believe this is mainly due to the fact that it axle is twice as long and that it takes up some of load in free torsional twist (spring), thereby reducing some of initial shock loading. The shorter the axle, the less twist it will take before it fails. From my experience, the point of highest torque load, related to weakest link in drivetrain, is at the left side inboard CV joint. I went through some calculations for my car and the torque load at that point is 4,550 ft lbs (using 1st gear ratio 3.50 and final drive ratio of 3.61), which is on the low side for "true" high performance racing splined axles.

Also found out that with a high horse/high torque V8 in a Fiero, there's no need to launch the car above 3,000 rpm, as it doesn't gain you anything in performance.

[This message has been edited by California Kid (edited 12-21-2001).]

I fixed mine with a small bead of silicone. Still holding after 2 years.

I believe the engine is moved over 2" on the Zumalt kit. I have that arrangement. I also have Zumalt's 4340 heat treated axles. So far no problems, but I don't launch at 3000 rpm either. Do you think the Mark Williams axles are stronger than the Zumalt? I'm trying to make an argument to go to the larger axles. Help me out here.

[This message has been edited by wcapman (edited 12-20-2001).]

quote Originally posted by wcapman: I also have Zumalt's 4340 heat treated axles. So far no problems, but I don't launch at 3000 rpm either. Do you think the Mark Williams axles are stronger than the Zumalt? I'm trying to make an argument to go to the larger axles. Help me out here. [This message has been edited by wcapman (edited 12-20-2001).]

I'm not sure exactly where Zumalt got his axles, heard a rumor it may have been Mark Williams, but not sure. Here's some info if you what to follow up with Mark Williams Interprises, Inc (303-665-6901) on the material spec. Their PN for may short shaft is 55008S-300-1 SPECIAL DBL SPL SHAFT 300M EA6547. This part is not on their Web Site as it is a special item. Picture scanned of standby replacement, full size.

Yes, exactly right, I just used the very-much *wrong* term, my mistake

I blame late-night posts. (hey, look at that time! Better post some more!)

Hyopthetically speaking, If I had these bearings, and they were leaking, I'd not try to pull them (unless I had access to a press and were splitting the case...)

I would probally drain the tranny, clean the area very well, then wire-wheel/sand it up, and gob a whole lot of Silicone RTV sealant on there, and maybe cap it off with a piece of bent sheet aluminum.

Next time I'd load them up real good with Rodney's supplied matching Locktite 515. (If you did that and they still leak, we'd be intrested in hearing about it!)

Best!
Ben.

quote Originally posted by California Kid: Ben wasn't talking about the differential bearings!!!! He was referring to the, for lack of better word, "pilot" bronse bushings that are located at each end of the trans case where the half-shaft goes in on each side.[/B]

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Ben Cannon
88 Formula, T-top, Metalic Red           "Every Man Dies, not every man really Lives"
88 Formula, Northstar, Silver                     -Mel Gibson, "Braveheart"

Something else to consider, since I haven't seen Archie on this thread I'll post it myself.

According to Archie's website, the Fiero axles are strong enough as is (with his kit, because it doesn't move the engine to the side). He's so confident in this, he states that if your axles break, he'll come out and replace them himself!

Of course, that doesn't apply to any swap where the engine/tranny is shifted. You have to get custom axles then. Archie has also mentioned one problem with that is the change in geomoetry from the shift is harder on the axles, making them even more prone to breakage.

Archie, if I've misquoted you or missed something, please set me straight.

Does anyone have any pictures of the HTD, Corson or Zumalt kits installed or on the cradle? Am interested in water pump and pully clearances, as well as shifter cable and transaxle on the other end.

------------------
Timothy E. Smith
1986 SE V6
1984 Coupe

quote Originally posted by tesmith66: Does anyone have any pictures of the HTD, Corson or Zumalt kits installed or on the cradle? Am interested in water pump and pully clearances, as well as shifter cable and transaxle on the other end.

With any kit that moves the engine, the left frame rail will have to be notched to make a space for the end of the transaxle.

quote Originally posted by Formula88: Something else to consider, since I haven't seen Archie on this thread I'll post it myself. According to Archie's website, the Fiero axles are strong enough as is (with his kit, because it doesn't move the engine to the side). He's so confident in this, he states that if your axles break, he'll come out and replace them himself! Of course, that doesn't apply to any swap where the engine/tranny is shifted. You have to get custom axles then. Archie has also mentioned one problem with that is the change in geometry from the shift is harder on the axles, making them even more prone to breakage. Archie, if I've misquoted you or missed something, please set me straight.

This is just my opinion, but the geometry doesn't change that much with the short shaft only being 2" shorter. It's really an issue of how much horsepower/torque is being thrown at the axle that makes is susceptible to failure. Archie will correct me if I'm wrong, but I think most of his conversions have been in the 300hp/250-300torque range. Now that he's playing with the newer V8's with more horse/torque which do move the engine/trans to the left more (similar to Zumalt-Corson-HD Elim), he may find the axle is on the borderline edge as well. As I stated above, the shorter axle is not as forgiving to twist as the long one, this is where the high horse/torque applications find the weak link (once you resolve that one, the CV's are next failure point, then trans).

Keep in mind these half-shaft's were never intended to take these kind of loads. As with any high performance application, the higher you go in hp/torque, you'll quickly find the limitations of the parts you're using. Also, a lot comes from experience of knowing the machine, what the limitations are, and driving smart.

The mid-engine layout really makes the tires "hook up" quick (hardly any tire spin with wide sticky tires), this results in tremendous loads to the driver. Anybody wanting to do smokey burnouts (without water) should consider hard compound or narrower footprint tires.

The clutch is another issue in this equation, a setup that "locks" 100% is going to throw more shock loading to the drivetrain, than one that "locks" 95%. Naturally 100% is better and generally has a longer performance life.

Rear suspension and cradle attachment anchorage points are other areas that affect half-shaft loading. Performance parts or modifications should be made to minimize the torque from forcing them out of their designed travel limits (meaning urethane, solid mounts, etc).

Bottom line is that there are many issues to be considered when "flirting" on the edge of design limits of factory parts. Choice of conversion kit really depends on what the buyer wants, can afford, smart enough to do it himself, or make better improvements to it. Like Archie says "How fast you want to go?", which really means, how much money do want to spend??

[This message has been edited by California Kid (edited 12-21-2001).]

I must want to go really fast cause I just dropped another $1200 on the rear suspension. First, I need to say that I'm on my 3rd set of Fiero wheel bearings. I've not had any problems with the shafts. (N*/Getrag/Zumalt) However I had a CV joint start clicking Monday night. Soooooo, Today I took off and hit the machine shops again.

I'm putting bigger bearings and CV joints on the rear. The inner CV joint will interchange with the larger size axle. However, we managed to find a CV joint that was larger but accepted the smaller axle, both inner and outer. Came from a Cadillac but don't know the model. Then I found a LARGE caddy bearing. So now I am modifying the spindles to accept the larger bearing and outer CV joint.

For those who don't know, I've fabricated some rear spindles in a manner similar to the fabricated spindles on the Held front end. They mount DynaliteII calipers and whatever bearing hub I choose. Since I already had them fabricated they went back to the machine shop this morning for "mofification." The CV joint guy has my extra long axle, and the bearing shop had to order an extra bearing since he just had one.
I'll do all my fitup with the long axle and have the short shaft modified when I do the work. Don't have an extra short shaft.

The new spindle design has a lower pivot rod to replace the ball joint. I'll have to fabricate some new lower a-arms,,,BUT there will be NO bumpsteer when this is completed. Interestingly, the a-arm ends up looking similar to the Held bump steer fix. I didn't copy it, but there aren's a lot of way to do that.

Talked to the CV joint guy about axles. He said he has never seen a broken shaft. Joints, yes, but no shafts. This is why I elected to stay with the smaller sized shafts for now. New larger diameter shafts would have been 400 more. I was thinking about the broken shaft problem. If there is any wear in the splined part of either the shaft or spider, it can put bending on the shaft and could result in breakage. Also overtravel of the wheel could contribute. If you take the overall axial torque through a universal (CV joint) the torque is multiplied by the vecor of the angle. So if you are accelerating under hard load and hit a significant bump, the short shaft will deflect more and possible overstress it. Frankly, i don't see that. It was probably just wear or a bad joint.

Now with all of this stuff being bullet-proofed is this going to fry the Getrag?

I'm doing something very similar, except with Pontiac 6000 (largest I could find that will still fit into the 88 rear knuckles withought machining them out beyond breakage points.)

I'm having new threaded hub faces made (and then pressed back in) to match my wheels and brakes' 5x130mm wheel bolt pattern. (bolts, not lugs and studs, ala newer BMWs)

Also, converting the rear end to entirely 'solid' rod-end piviots. NO flex.

We'll see! I don't think I'll have any getrag issues, theyre really amazingly STRONG trannys!

Best!
Ben.

------------------

Ben Cannon
88 Formula, T-top, Metalic Red           "Every Man Dies, not every man really Lives"
88 Formula, Northstar, Silver                     -Mel Gibson, "Braveheart"

quote Originally posted by wcapman: Talked to the CV joint guy about axles. He said he has never seen a broken shaft. Joints, yes, but no shafts. This is why I elected to stay with the smaller sized shafts for now. New larger diameter shafts would have been 400 more. I was thinking about the broken shaft problem. If there is any wear in the splined part of either the shaft or spider, it can put bending on the shaft and could result in breakage. Also overtravel of the wheel could contribute. If you take the overall axial torque through a universal (CV joint) the torque is multiplied by the vecor of the angle. So if you are accelerating under hard load and hit a significant bump, the short shaft will deflect more and possible overstress it. Frankly, i don't see that. It was probably just wear or a bad joint. Now with all of this stuff being bullet-proofed is this going to fry the Getrag?

Hey guy, keep a notebook on these parts and changes, may help a lot of us down the road!
I can tell you the hardened alloy shaft did break clean at the joint, neither shaft or joint receiver showed any wear or slop. But like I said, that shaft had 20,000 very hard miles on it, with numerous hole shots. It was the same shaft that was used in finding a clutch setup that would take the horse/torque, fried 3 setups from different high performance clutch suppliers before trying QuarterMaster double disk setup. This meaning it was beat pretty darn hard. The fracture face of the shaft only had minor indications of torsional twist, the outer diameter (at the fracture) got beat up a little after the failure, so it's hard to say if there may have been a stress riser (nick / slight groove) in the shaft in this area. Long story short, I'm surprised it lasted as long as it did. The second failure was directly related to soft stock shaft (twisted), stressed CV internals (numerous fractures), and sloppy trans case pilot bushings. CV Joint and pilot bushing more than likely contributed to the failure of the hardened axle (1st failure), which could have been a long term fatigue failure from minor harmonic vibration resulting from the worn parts.

You bring up a good point about max suspension travel related to forces against the shaft and CV. I know my back end really squats low on hard throttle take offs. Koni's are set firm, not extra firm, which lead me to believe that it might be worth fabricating hard rubber "travel stops" to limit maximum suspension compression.

As far as the trans goes, I think you'll be OK. Don't really know what horse/torque/tires you're running.

To anyone else reading this, don't be concerned unless you're going into or beyond the 350hp/350 torque range. This is just an unknown "grey area" of working out a bug that might come up once in a "blue moon".

Just my opinion.

Squat is kinda a low speed valving thing and setting the shocks to firm may just slow it down a tad. Best to have hard rubber snubbers or something. I'm preparing for Alan Johnson cams and Paul Vanderley heads. Should bump the N* up to 365 hp (according to Alan, who I guess has dynoed one). The real shocker is the red line will be up around 8500. Alan said to set it rev limit at 9000 but the engine would be good to 10,500. I can't imagine anyone in their right mind attempting that. I had Alan grind the cams to limit torque to 345 ft/lbs.

As far as squat goes, think of a socket on the end of a long extension with a flex joint. As soon as the extension goes out of column (straight) you have to put more force on the wrench to turn the same bolt. There is a vector load trying to take the whole thing more out of column. This may be happening to your CV joint. And the shorter the axle the more the force.

I have noticed that when I jack the car up the short side axle inner CV is put in a really sharp bend. If you have that same problem and you jacked your car up a lot you could have caused the joint to notch the shaft and cause failure. I'm going to watch mine more closely.

Do you have any trouble with the Quartermaster and launches? I've been real reluctant to side step the clutch. I don't doubt the clutch would hold, but I had to abuse the tranny.

I'm running Firestone Firehawks 255/50/16's. They seem to be pretty sticky for a street tire. I had BFG TA's and they would really spin. Had a few of the early v-8 guys say that was good thing to keep from loading up the tranny.