Awesome rear differential explosion in SLOW-MOTION on my Eclipse today at the track!

[kp116]

It was nice to see you again Tim. Sorry about your rear end. Atleast peeers and J were able to get it on camera! I guess this will give you time to get everything dialed in and to know how your car sits.

 

[twicks69]

Actually, the video really helped out, as I now know that I am going to be decreasing the rebound on the rear struts, increasing the rear spring rate up to around 1000#, and increasing the rebound on the front struts.

Hopefully that will help combat the dreaded rodeo bouncing and get it launching smoother.

Thanks guys for all the good times! Had an absolute blast, even if I blew my stuff up!

Now, I just need to find some rear axles, driveshaft and subframe....

 

[rx7ttlm]

my $0.02, you might look into the TRE spool. Talk to john and ask him what he thinks. The shock loading from the front slipping, transitioning to the rear slipping back and forth I would imagine was a significant contributor to your failure. and after that do another run with video and see if your still under 50% critical damping, ie more than bounce, bounce, settle and valve shocks from there. Suggested reading would be something like bilsteins shock theory / manuals. along with ohlins 044 info. Cheers

Patrick

 

[twicks69]

Thanks Patrick for the advise, I already have suspension theory books that I have read/or am reading.

As well, I already have tried the TRE spool, a few welded diffs, and numerous 4-spider diffs.

The viscous center with 4-spider setup I am running is substantially more forgiving than a welded center diff or spool. I would have broken my rear diff a long time ago if I did a launch like this on one between the fact that there is increased driveline shockload, and increased power distribution to the rear wheels.

The bounce in the suspension is what killed the rear differential, not what kind of center differential I am running.

 

[95eclipser]

evo3 diff conversion

is there any advantage to going evo 3 diff route? ^^^^

iv searched but ill i find is "evo 3 16g", "evo 3 motor swap", "evo 3 tranny"......ect no real info on the conversion?? thanks guys

Drew

 

[marcmsj]

That's painful to watch... especially in slow motion!

 

[black_gst]

is there any advantage to going evo 3 diff route? ^^^^

iv searched but ill i find is "evo 3 16g", "evo 3 motor swap", "evo 3 tranny"......ect no real info on the conversion?? thanks guys

Drew

EVO 3 DIFF

 

[95eclipser]

your the man Adam! thanks for the bushing and info on the evo 3 diff.

 

[gastroker]

that's a sick video. I want a camera that does that. Sorry about the breakage, but upgrades are always fun.

 

[talontd92tsi]

Only two words come to mind.

Oh SNAP!

 

[1 fast evo 2]

Thanks Patrick for the advise, I already have suspension theory books that I have read/or am reading.

As well, I already have tried the TRE spool, a few welded diffs, and numerous 4-spider diffs.

The viscous center with 4-spider setup I am running is substantially more forgiving than a welded center diff or spool. I would have broken my rear diff a long time ago if I did a launch like this on one between the fact that there is increased driveline shockload, and increased power distribution to the rear wheels.

The bounce in the suspension is what killed the rear differential, not what kind of center differential I am running.

I would beg to differ Tim, after watching that slo mo video I would say you have all kinds of problems going on at the same time. The 4 spider diff IS a large part of the problem with your car but then there is the whole rear diff. that is mounted for s--t from the factory, the suspension moving way too much and I'm sure there are several other factors involved as well.
I'll give you a call and we can talk-that video was badass man. I wish I had slo mo of some of the stuff I've blown up over the years.

Mike Reichen

 

[twicks69]

Thanks Mike, I always appreciate your advice!

I am going to deal with the 4-spider at a later date, and try to focus on suspension work, solidifying the rear end/subframe/mounts/bushings, etc. Then, move onto the center diff if I just keep the spool in (installed to get the car home in FWD mode w/o transfercase/driveshaft/diff/axles), or swap in the 4-spider.

 

[habitatguy187]

Tim out of curiosity why haven't you switched over to e85? I've been seeing a lot of the guys that have been around a long time sticking to c16, what's your story?

 

[twicks69]

I like to use it as cologne, so I use it in my car since it is at the house.

Well, regarding that, I have been tossing around the idea of running E98 for a few years. I should be able to make my power goals on VP Q16/VP Import and the fuel capacity should be there for running E98 with the quad fuel pumps after I get a second set of injectors on the car.

I know that the power can be made on each fuel, I just have stuck with one instead of changing that due to the fact that race fuel is plentiful around me, and E85 and E98 are just making their way into the region. My friend is a supplier of E98, meth and VP fuels (Schmitt's Race Fuel), so it is now an option to play with more.

I will stick with the current setup to get tweak the bugs out then I will maybe consider changing fuels.

 

[kwboost]

Twinks69,
Awesome video! I am in a similar situation as you. I am making about 700hp. About a year ago, I went to the track and broke rear end, rear drive shaft yoke, axles, diff cover, and front diff spider gears. Single pass.

Since then I have upgraded the suspension. full prothane kit, dsm graveyard 800hp axles, custom rate qa1 springs, solid diff bushings. I have a welded center diff, and had Jon at TRE shotpeen the trans (including the front diff spider gears) then added a phantom insert up front.

I am interested to see how stiffing up the rear works for you. I actualy softened up the rear. 250lb springs and also softened the damping on the agx's. cars pretty light. 2650lb I dont have a lot of testing done with the changes. but with the passes I have made so far have been smooth. and no more bouncing.

Also, are you looking into methods of bracing the rear end? the stock mounting locations are crap. I am looking into this cover Frontline Fabrication - Products: 2G DSM Rear Differential Cover
Thinking about the girdled version.

Here's a vid of it leaving on the new set up. was on the street of course so not a great comparrison, but you can see it was a smoothe launch.

 

[twicks69]

I already have that rear differential cover with the girdling; it will be going on the new setup.

I am sure I will need quite a bit of suspension tweeking to get it perfect off the launch. I will just continue videotaping the launch to get a better handle on all the variables I am dealing with.

 

[504awd]

I already have that rear differential cover with the girdling; it will be going on the new setup.

I am sure I will need quite a bit of suspension tweeking to get it perfect off the launch. I will just continue videotaping the launch to get a better handle on all the variables I am dealing with.

u didn't have that cover on when you car broke though am right?

 

[twicks69]

Correct, the stock rear diff cover was still on the car when it broke the rear end.

 

[Mr Peepers]

Great to finally see your car run! Wish it hadn't broken but I know it will come back stronger

Hope all is going well, I look forward to seeing it back at the track and ready to kick some ass.

 

[talont3t4]

I build my own cover and have been good ever since. Someone needs to setup and make some heavy duty ring and pinions for 2G's I know several people that would be interested. Good luck.