96 BMW 328is LS1 to LS2 Conversion Bimerok

[bimerok]

A quick update...

So last week I was driving on the street and accelerated semi-hard in 2nd gear over somewhat rough piece of road and then this happened:



So the axle got snapped somewhere on inner CV Joint and pretty much is held just by the rubber boot. This is what it looks like:



Luckily I was not too far from home, so my brother towed me with a rope (a ratchet strap) on his 540 Also, haven't opened the boot yet to see what it looks like inside. Curious to see if there is anything or any repair kits to try and fix this axle to keep it as a spare.

I'm impressed that it held up as long as it did with so much track time that the car had. It's been about 6 years of LS1 and then LS2 power going through these axels

Luckily there is a guy who parts these cars about 45 minutes away from me and he had one available. So $50 and about 45 minutes on a jack stand and the car is road-worthy again.

If anyone is wondering what it feels like when you snap an axle, it feels and sounds like your car just popped out of gear. This is exactly what I felt and thought when this happened. Then you pretty much can rev the engine in any gear just as you could in neutral. There is a very slight feel of movement because I have an LSD differential, but not nearly enough to get you going...

[TipsyMcStagger]

Interesting that this happened. I was just wondering about the strength of non-M axles while I swapped-in an LSD the other day. It was the first time I'd really messed with any of those components and while I knew the flanges were different between M and non-M axles, I learned that the M flange diameter is larger than the non-M. It made me think about the potential difference in strength between the two.

As I pondered this, I thought to myself, "well, Leo has been running non-M axles for a long time with no problems." LOL.

I wonder if it wouldn't be a bad idea to stockpile a replacement or two? They shouldn't be too hard to source from those who do part-outs.

Tipsy

[bimerok]

that is funny.

[douglee25]

Ha. Gotta love it! Nice hearing from you.

Sent from my VS990 using Tapatalk

[Albertan]

Well, that answers my question. When I did my LS swap I went with the E32 diff and M3 suapension/axles etc. I always wondered if it was over kill. Guess it wasn't.
Also interesting that you were able to tear it up while driving and not a hard launch. Were you getting axle hop when it happened? I know that can be a real killer.

[bimerok]

The oem 328 axels and 188 M3 diff is working out fine if you use the car for street. For road coarse too. After that many years of LS1/LS2 track use I can't complain. Afterall these are 20 year old parts with over 100K miles getting some extreme use at the track. I still believe that they are adequate enough.

The axel that broke always looked weired to me when I was under the car countless number of times. Even prior to LS1 swap. It was always kind of lose moving on CV Joints compared to the other side and yet it held up for so long.

It broke while I downshifted 3rd to 2nd, releasing clutch and applying gas fairly hard. I happen to synchronize this while going over some rough road patches. Having pretty hard, track setup suspension did not help the cause also. I guess all together it put enough strain on the old axel to take it to its breaking point.

If you look at the track guys breaking axels and diffs under stock power, I think I'm well under the breaking curve

[Albertan]

Yes but remember when BMW took their old "seasoned" blocks out of old cars for the F1 program. The idea was after many heat cycles that stress would be normalized or the block would already have been cracked. Probably same with the axle. The CV joint might have worn to give more play. then the rough road and hammering it in 2nd just finished it off. Now you will have to spend $20 for another at a PickNpull! Cheap repair. Good thing the rubber held together. A half axle swinging around could have been expensive.

[bimerok]

Alt Pulley Clearance.

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[wbrentr]

How is your new diff holding up? Is it the 3.23 M?

I'm worried about mine, not so much tracking it, but hard launches. What power are you putting down?

[bimerok]

So far diff this diff (2nd one) is holding up fine. It is 3.23 M. Not sure how much will yours survive with had launches . I’m sure stock axel shafts will go first.

On power, I have stock LS2 out of GOAT with 400hp/400ft-lb plus whatever long tube headers, dual 3” exhaust and cold air adds. Oh and throw extra few HP for couple of vinyl sticker that I have

[wbrentr]

So far diff this diff (2nd one) is holding up fine. It is 3.23 M. Not sure how much will yours survive with had launches . I’m sure stock axel shafts will go first.

On power, I have stock LS2 out of GOAT with 400hp/400ft-lb plus whatever long tube headers, dual 3” exhaust and cold air adds. Oh and throw extra few HP for couple of vinyl sticker that I have

I'm about 475hp/430ft-lb. I assume I will be safe on the street & track as long as it isn't a drag strip. I'm not making that much power now as I'm still needing to tune it.