The downside of sticky tires.

[FuzzyDunlop]

Results of last weeks session at the track. Dropped the clutch at around 4000rpm and heard a *SNAP* Meanwhile Im sitting there flooring it and not moving an inch. The guys at the track had to push me off to the side while someone from behind yelled "Take it to the dump!"... sad day.
I pretty much knew exactly what happened before I looked under the car.

Left side axle snapped right at the hub.

 

[natto fire]

It takes torque to snap them like that, if that is any consolation.

At least you weren't this guy: Corvette clutch fail

Going to go out on a limb and guess those are not OEM? It is kind of sad to know that when you replace a part, it is usually of substandard quality compared to the original part, albeit newer.

 

[_Rick_]

I'm somewhere between :awe: and


Might be a case of some bad metallurgy though. I'd usually expect an earlier part of the power train to throw a fit. Clutch, trans, diff, that kind of thing.

 

[exdeath]

Take it do the dump? Half those douchebags only dream they had enough power or grip to snap an axle.

 

[exdeath]

I'm somewhere between :awe: and


Might be a case of some bad metallurgy though. I'd usually expect an earlier part of the power train to throw a fit. Clutch, trans, diff, that kind of thing.

Gearing puts a ton of leverage on the axles.

 

[FuzzyDunlop]

These are aftermarket axles and are supposed to be built to handle 450hp. I'm only around 260 (if that) so it does seem strange that it snapped. The place I bought it from is replacing at no cost.

As far as where it snapped, this is possibly the weakest part of the entire axle, everywhere else is super bulky.

and exdeath, ya, I know, I thought I might be one of the slower cars that night but there were a tonne of slow cars there. Like guys in Hyundai tiberuns , and vw golfs, comparing engine bays then only running 15s. The look on their faces when I told them that i ran a 13.5 without even trying was kinda funny

 

[jaedaliu]

congrats on finding a shop that stands behind the product they sell. Must have been a manufacturing / materials defect. (or super inflated specs, but i doubt it)

 

[exdeath]

No LSD? Next upgrade!

 

[Throckmorton]

What car is this??

 

[exdeath]

What car is this??

1986 gen 1 MR2 with a 3SGTE turbo engine from a gen 2 MR2.

Popularly known as a Mk1.5

 

[NutBucket]

and exdeath, ya, I know, I thought I might be one of the slower cars that night but there were a tonne of slow cars there. Like guys in Hyundai tiberuns , and vw golfs, comparing engine bays then only running 15s. The look on their faces when I told them that i ran a 13.5 without even trying was kinda funny

15's? The last time I was at the track there were plenty of people running 16. A friend decided to run his 1.6L Pulsar just for fun...18.xx Man, this was probably a decade ago.

 

[FuzzyDunlop]

15's? The last time I was at the track there were plenty of people running 16. A friend decided to run his 1.6L Pulsar just for fun...18.xx Man, this was probably a decade ago.

ya, hehe, there was a Smart Car than ran against a old beat up oldsmobile. The smart car ran a 23.5 and the olds ran a 18 haha. it was entertaining. There was also an 198* mustang that rolled to the line and was completely silent, when he took off he was still completely silent, but he ran the 1/4mile with a 8.74! LOL, it was weird.


I have a LSD but its a viscous LSD, which operates with fluid somehow. Apparently that fluid tends to break down over time and is not replaceable. My car still leaves two || when I launch on dry pavement so i believe its still working fine.

Im just glad the axle snapped instead of something else internal breaking. This is an easy fix.

 

[FuzzyDunlop]

At least you weren't this guy: Corvette clutch fail

hehe, ya or this guy
http://www.youtube.com/watch?v=nK9TX82c2VI

 

[JCH13]

Pics of the other side?

The spiral fracture is really cool, indicative of failure in torsion (go figure).

You'll be back on the track in no time.

Also, Wiki on VLSDs: http://en.wikipedia.org/wiki/Limited-slip_differential#Viscous

 

[Black2na]

Defect in the axle, read the drag forum on mr2oc usually the diff breaks after you upgrade the cages. I've never seen one break like yours. Don't be afraid to give her the stick next time. I've seen mr2 stand on the rear tires with the same axles in the turbo mr2's

 

[MagickMan]

Looks like bad luck in getting a bad part.

 

[jlee]

+1 on faulty part. MR2s can lift the front end on stock axles / upgraded CVs. The transmission is bulletproof. Clutch should be the first failure point, then possibly diff - if you avoid wheel hop you should be solid to 600+rwhp.

 

[FuzzyDunlop]

Ya, gotta be just luck of the draw. The place I bought the axles from it's being really cool about it.

On a side note, was wondering if I should set up my car differently for running at the track. Should I raise the front end up an inch and soften the dampers to allow the car to sit back when I launch, thus allowing weight transfer to the rear for a little more traction? Or should I keep everything as low as it goes and tighten up the dampening?
I'll have to do some research.

 

[Gillbot]

I avoid parts that are rated by "hp" since torque is what really matters.

 

[JCH13]

Ya, gotta be just luck of the draw. The place I bought the axles from it's being really cool about it.

On a side note, was wondering if I should set up my car differently for running at the track. Should I raise the front end up an inch and soften the dampers to allow the car to sit back when I launch, thus allowing weight transfer to the rear for a little more traction? Or should I keep everything as low as it goes and tighten up the dampening?
I'll have to do some research.

Nope.

http://www.turnfast.com/tech_handling/handling_weightxfr

How can Weight Transfer be Minimized?
Contrary to what you may be inclined to believe, the amount of weight transfer is not altered by springs, shocks, anti-roll bars, etc. Weight transfer is a result of inertia and momentum. These suspension components cannot change that. What these components can do is impact how much the suspension moves in response to the load change, and how quickly the load transfers to the tire contact patches.
The amount of weight transfer is dominated by the vehicle's weight, location of the center of gravity, wheelbase, and track, and the amount of force applied during braking, accelerating, and cornering.
Weight transfer is a function of the vehicle's weight and the forces acting on that weight. Reduce the weight, and ou reduce the product the of the forces involved.

I wouldn't get too crazy adjusting your suspension for drag racing. Just keep enough damping to prevent wheel-hop and you'll be good to go.

I wouldn't lower it much, if at all. In fact, I would keep it near stock ride height to help increase weight transfer and let the suspension operate in a range where it's most happy. I would not setup much camber in the rear, and I would use fairly stiff springs. I would do this to minimize negative camber and reduce camber changes on the rear tires, these will hurt your longitudinal grip.

I'm no drag racing guru, I just know a little about chassis dynamics and how to make tires happy :awe: