GI: Affordable Helical LSD's for the G-series!!

[Dan [Sac]]

Alright, back from the strip after 48 hours of intense work.

The news is mostly bleak. I'll start with the good news. I went back to the dyno last night to tune fuel for 25 psi of boost, and was there till 2am (didn't get on the rollers till 11pm). The LSD held 50 dyno pulls without a hitch (numbers between 340 and 500 whp, 350-490 lb-ft). 20 psi was the max attained, I think my 10psi wastegate spring is getting tired.


Today at the track the car lasted exactly one burnout and when I lined up and launched it moved exactly 13 inches. Something inside the driveline broke, and as of right now I don't know until I tear it down. Engine runs, gears engage, but nothing happens. I've never broken a first gear on launching, and I wasn't any more or less aggressive than usual. 5,000 rpm launch with the 26" slicks at 5.5 psi isn't exactly light duty though.

So, tomorrow or monday I take down the transmission and I do the autopsy and see what's up. There are chances that the clutch expired, but there are no noises or parts floating around.

The only visual cue that something is amiss is that the driver side axle is sticking out of the transmission about 1/8" more than usual. I don't know if this means that the diff. moved or if it just kicked out the axle a little or what the deal is.

So between yesterday and today I dropped $500 (dyno, alignment, track fees, fuel) and have nothing to show for it, but we'll try again. There are good days, and bad days, and this was definitely closer to bad than good.

On another note, I will never buy any tools that don't say "Made in the USA/Japan/Germany" ever again.

Dyno at 2 am....at Midnight Performance, ironically:

[smoke187]

wow that don't sound good at all

[therieldeal]

i did note a **very slight** amount of extra in/out play on the axle compared to stock, but mfactory assured me it wont be a problem. it was still well within tolerance for the seals to seal.

hopefully the problem is nothing LSD related. i'm assuming the shifting problems you were initially having went away?

[Dan [Sac]]

The only issue left post-install was still no reverse. Something I'll also be looking at upon teardown.

[therieldeal]

it had to be an assembly issue - both trannys that i test installed in would shift into every gear just fine on the bench. the LSD doesnt really get anywhere near anything shift-related.

[deadly_sleeper]

that sucks to hear dan. but i'm glad that you're doing the testing for us and keeping us involved and informed. i'm interested to hear what ends up to be the problem, and i hope you are able to get it fixed and have it up and running soon for further testing.

[1992tracerlts]

see guys... not saying its lsd related. But thanks dan for testing! Hope to see diagnostics tommorow.

[Skuce]

taking apart trannies is fun....umm....ya

[MD323]

thanks for going all out for the community dan. hopefully whatever it is will be a quick and cheap solution.

[HondaStomper]

Damn dude that sux... The LSD will get done eventually... i hope you get the car up for race season... Hopefully it's something simple...

[Dan [Sac]]

So what's going to happen now is I'll take the gearbox apart this week and see what the damage is. If the LSD is intact, then I'm going to wait till the PAR gears get here (supposed to ship within weeks) and have an actual FWD race shop assemble the thing and try again.

If the LSD is damaged or will need significant repair then it will go back to MFactory and I'll wait for the fix and then put it in the PAR-geared box and go at it again.

[therieldeal]

*crosses fingers that it was just some flimsy mazda part that broke*

[leo323]

i thinck you broke the screws on the lsd and ring gear ....

[therieldeal]

it broke right on the line, the car barely moved

[MATT91GT]

wow that sucks. it did last all those pulls. even tho i am not in the GB i hope that it was another transmission part that failed. im looking forward to seeing the answer.