Broke Stub Axle

[jschwartz]

While Drag Racing at the Bristol Bash in Tennessee.
It happened during my wet burnout to heat the tires.
Anyone else broken one?
I thought this stuff was good for 1000hp?
A big thanks to Ken Wright who gave me his upright to get me through the event and back home, since I had driven it there.
I also won the Autocross (Pylon course time trials) with the fastest time of all the cars, even those with race tires.
jeff schwartz

[GTRmannen]

But how did it go

[jay esterer]

I met the John at K@N USA, he built the K@N Ultima. It broke rear stub axles, outer CVs,killed the rear bearings and broke half shafts with a 600 hp SBC.

Ultimas are street cars not race cars. Sometimes we get confused about that-I know I do.

[gtr-tt]

That sounds alarming. I guess I just send mine back to the factory, not even worth mounting them if they brake so easily

[maajola]

Shit!! this is not good at all.

[davefiddes]

Both Andy and Clive take their cars to the strip on a regular basis. I think I'm right in saying that they've had no problems with stub axles. I think Andy had an issue with driveshafts but it turned out that he was running the stock Ford Granada ones rather than the GKN Motorsport ones that the factory currently supply. Maybe it was just a dud one?

[Stig]

gtr-tt said:

That sounds alarming. I guess I just send mine back to the factory, not even worth mounting them if they brake so easily

Errr.. that's a bit of an over-reaction isn't it?

Just because one owner had a problem when using the car in a fairly extreme fashion, hardly warrants writing off the drive shafts as being useless does it?!?!?

[GTRmannen]

Stig said:

gtr-tt said: That sounds alarming. I guess I just send mine back to the factory, not even worth mounting them if they brake so easily Errr.. that's a bit of an over-reaction isn't it? Just because one owner had a problem when using the car in a fairly extreme fashion, hardly warrants writing off the drive shafts as being useless does it?!?!?

NO i don't think so

Becouse if they don't stay in one pice when he is using them ,there is no chance when we "HP" abuser is going to give them some

[MattYorke]

Has anyone actually discussed this with the factory?
If not, it'd be worth getting their input (and posting it here) before this turns into another panic session like the fuel pipe diameter debate previously.

[jschwartz]

I've emailed Ted, but I've been having trouble with my email. I called them today, Ted's out, so is Richard.
Talked with Andy. They've never had this happen.
Jeff

[MattYorke]

Yeah, I asked Richard to quote me for modifying my engine and box mounts to put a chevy in, plus another couple of bits, but he hasn't called back yet either.

[k wright]

Fast time of the day on the autocross track was pretty impressive, especially if the Lotus Seven clone with a two rotor 13B ran the course also. There were plenty of Miatas there. Jeff gave me a ride around the autocross course and it was weird having a car that wide turn so well into tight corners.

[andycanam]

Need to be clear as many here are talking about different bits.

Both myself and Clive are running the GKN drive shafts now and they have proved bullet proof so far, and they are quoted to 1000bhp.

But my understanding is that the Sub axel or shaft is the steel bit that rotates in the upright and attaches to the drive shaft.... to me it sounds like this is what has broke.

My experience is that even the lower spec (non GKN) stuff will survive most things but not a lot of hard standing starts...... but then my understanding is that if you drop the clutch in a lambo the clutch only lasts a couple of launches!

[k wright]

The drive shafts held up fine. When we got the car in the shop we were prepared to pull the transaxle to repair a clutch or swap transaxles. It was when Jeff lifted the right side axle away from the upright with no resistance that the diagnosis was made obvious. If you want pictures either Jeff or I can supply them.

ken

[james]

andycanam said:

but then my understanding is that if you drop the clutch in a lambo the clutch only lasts a couple of launches!

Too true. I tried out a Diablo a few years ago. The sales bloke actually said. "It'll do 0-60 in 3.9 seconds. Once. Then you'll probably need a new clutch." I didn't buy one.

A lot of cars have a weak spot. Any car will have a weak spot if you abuse it enough. There will always be one component of the drivetrain that is weaker than the rest, and therefore is the first thing to go when you increase the stresses. That's not to say it's a design fault (ok, I'd count the Diablo clutch thing as a design fault, but then they're designed for cruising the Kings Road at 20mph, so the clutch isn't actually going to take much punninshment ).

[andycanam]

k wright said:

The drive shafts held up fine. When we got the car in the shop we were prepared to pull the transaxle to repair a clutch or swap transaxles. It was when Jeff lifted the right side axle away from the upright with no resistance that the diagnosis was made obvious. If you want pictures either Jeff or I can supply them. ken

Ken hats off to you.... I know how important it is to have a friend around to help out especially when so many miles from home.

The same happened to me when my CV joint failed at the strip.... it was only the help of a local Ultima owner (GTRCLIVE) who drove home & back to collected a spare one that allowed me to drive the 100+miles home.

[gdr]

I noted that a Zonda snapped a driveshaft during a recent Autocar group test as well.

[Stig]

And a Noble's front suspension broke recently whilst being tested too.

So nothing's immune.

[doc_fudge]

I must say that Im reading all this with interest as Im preparing to order...and Im not all that concerned. Sure some people are having some problems some of the time... but no one is having all of the problems all of the time, so Im satisfied with the factory specs.

Andy