[McRat]

As some of you may know, we had a lot of problems with Getrags in the last year:

3.42 stock unit - Cut high 1.6's, 500+ passes, 391rwhp max, no problems.

4.10 Dynotech race unit - Cut low 1.6's, 50 passes, explosive failure taking the trans with it. Gears shattered.

3.73 Motive geared unit - Cut 1.6's howled like a bitch after one pass. Too soft.

3.73 Motive geared unit - Cut 1.6's howled like a bitch after one pass. Too soft.

Now we switched to the SDPC Getrag 3.73's. After 50 passes with down to 1.56 60's NO HARDENED OUTPUT SHAFT it still makes zero noise, and can hold 440 rwhp with ease.

I would tentatively give it a 10 (We have seen nothing to fault it on) as a drag rear. We could not out 60' it with 4.10's even. Super-sticky tracks have not busted it. Zero noise over stock.

When we hit 500 passes again, we will give an update.

:guiness:

 

[McRat]

Damn that sig is old!!! :mah:

 

[Dope]

Curious, are you still running the Exedy twin or are you running a different one now?

Dope

 

[JBsZ06]

Couldnt agree more. I have the Getrag 3.73 unit and (I happended to also have the )hardened drive shafts and its a great setup.

Glad your having such fun.

JB

 

[McRat]

Curious, are you still running the Exedy twin or are you running a different one now?

Dope

We switched to the Spec 3 for a softer launch. But the 60's improved. Looks like a good combo. Now to get the power dialed in.

The only gears that shattered were the Motive 4.10's. But trust me, life gets very, VERY expensive when the gears shatter. Way over $5000.

 

[Dope]

Hmph, interesting. Kinda a tough comparison because how many rears did you blow with the Exedy? Seems a lot of guys with the Exedy are destroying their drivetrains. I bet any of those rears would have lived a lot longer with a softer hitting clutch.

Dope

 

[Dope]

Oh, and were you running a diff strut (any brand) on any of the rears?

Dope

 

[McRat]

Hmph, interesting. Kinda a tough comparison because how many rears did you blow with the Exedy? Seems a lot of guys with the Exedy are destroying their drivetrains. I bet any of those rears would have lived a lot longer with a softer hitting clutch.

Dope

1.56, 50 passes. Enough said. You cutting mid 1.5's?

 

[IT L GO]

Glad to hear you have a good combo :z: :z:

 

[Dope]

1.56, 50 passes. Enough said. You cutting mid 1.5's?

What? Where did I say anything about my car? I've never even taken it to the drag strip!

Just asking questions, sheesh.

If I could find the confused smilie, I'd be using it.

Dope

 

[Zrod]

McRat

Thanks for the info, useful stuff for those of us still trying to figure out what suits us best. Sorry to hear it cost so much to get to where your are now.

Best to Ya
Zrod

 

[McRat]

What? Where did I say anything about my car? I've never even taken it to the drag strip!

Just asking questions, sheesh.

If I could find the confused smilie, I'd be using it.

Dope

Sorry, just a little grumpy over the whole ordeal.

Here's a recap:

With the Exedy, we had 3 rears in the car. The DTE exploded, but the Motive 3.73's were just too soft and gauled the faces. They did not come apart, the faces were too soft, and Motive does not warranty their products. The Motives were strong enough to find that the next weak link was the trans output shaft (main shaft) which sheared off, and the bell hsg, which broke.

We are assuming the Exedy had something to do with the failures, but don't really have proof. It actually felt very good, and was an excellent street clutch.

If in fact the Exedy caused the failure of the 4.10 rear, we don't understand why the main shaft and bell hsg didn't give first.

Trans brace has nothing to do with it. None of the failures originated at the case mount. Output shafts (1 DTE, 1 OEM, 1 Stock) were not an issue, except the DTE unit which was too soft and twisted. It did not cause a failure.

All we know at this point, is the combination of the Spec III and SDPC/Mallett/Getrag 3.73 rear has proven to outlast either the DTE 4.10/Exedy and the Motive 3.73/Exedy on our car. Out of all the gears in the car, the only explosive failure was the 4.10's.

I do apologize for immediately putting 100% of the blame for failure on DTE. We were one of the first cars running the Exedy dual, and had heard of no other problems at that point. We suspect it was a contributing factor. However I do not apologize for saying 4.10's are weak, for saying the DTE output shaft is junk, and saying that the gears were not radiused as claimed by DTE. Nor do I apologize for scoffing at DTE's initial claim that a lack of trans brace was to blame. It was in fact a gear failure at the root, which exploded everything it came in contact with.

Your results may vary. :guiness:

 

[BQuicksilver]

Thanks for sharing this info! I can't blame you for being a bit passionate about it after some bills I'd hate to have seen myself.

I'm in the market for the exact same H/C combo (maybe slightly milder cam) you're currently running. I road race, and don't want to go too big or change gears, but I would be interested in what you recommend to beef up the drivetrain for a guy like myself who hits the strip at times on street tires (other than a clutch).

 

[McRat]

Well, until we see something better come out, the SDPC/Getrag (which were originally made for Mallett) should be a good choice. The reduction in gearing will still give you about 175mph in a H/C car in 5th, which should be plenty of top speed, and perhaps be a little quicker around the track, since you should be able stretch 4th out by running 7000rpm with appropriate valve gear. We put in a heavier trans shaft, and a trans brace. Kat knows which brand, but I don't have my notes with me.

 

[Dope]

No worries McRat.

Interesting how you broke different things at different times. Is there anything you haven't broken? Half shafts I guess?

I'm running an Exedy single with a little less power (~420rwhp) and a DTE 3.90 rear and I'd be absolutely sick if I blew something up. Threads like this make me nervous Maybe I should just use street tires for the rest of my life!

Dope

 

[McRat]

Personally, I'd worry more with street tires than slicks or cheater slicks. Sharp impacts are more lethal than high loads. Many folk have busted gearsets on regular street tires or drag radials, and in my experience, I'd say more. The softer sidewalls on the race tires absorb sudden impacts. I've seen cars that can barely go 2.0 on the 60's shatter parts on the launch or 1-2 shift. Not to mention on the street.

Because of this, we avoid running street tires when drag racing. It certainly worked for us the first 2 years. We did ALOT of passes on ET Streets, and less than a dozen passes running street tires.

Your 3.90's and single disc are probably much safer than a dual disc and 4.10's. The thing that sucks the most is the 4.10's did not even make the car quicker. We are getting better 60's on the 3.73's with less HP.

 

[BLU-BY-U]

gees, mcrat and co have certainly endured more than their share of rear end grief. Thats some terrible luck. Glad to here this new setup is working out. Are you still running the rpm brace?

 

[PB24daGRK]

i've seen the Blue Meanie run in person, it's one little monster! :jammin: my friends were amazed when i told them your wife makes her own passes down the track and can probably outdrive most of the guys there

back to the subject, all i have are headers, exhaust, intake, tune, and about 398rwhp.......should i be concerned at all about the rear end? i've only ran on the eagle f1's and have pretty sh1tty launches, so am i safe to assume that i should be fine considering 99% of my driving is on the streets and drag race once a year?

thanks

threads like these make me nervous :eek2:

 

[J-Rod]

I agree with the comments on the Exedy. It hits hard (too hard IMHO) we broke the rear on Tommy's car on the first pass. Then the Exedy gave up on us after the 5th pass (you can't slip it).

So, we're using an Oz700 from Textralia which is fantastic.

We're running 4.10's and both DTE shafts. We're 60' in the mid 1.4s with it the last time out...

Glad to hear you are on the road back...

 

[vetteheadracer]

I have the Exedy Twin Plate on my Twin Turbo and am interested in your comments as I am taking it drag racing for the first time in a couple of weeks! I have dragged my C4 vette and dragged the Z before the turbos but not since.

I had a problem with the heat from the drivers side turbo giving a "soft" clutch, but this was due to the hose from the master cylinder to the actuator passing so close to the turbo it melted the plastic clip inside the coupler and eventually this failed meaning clouds of white smoke as it squirted clutch fluid on to the turbo :flaming:

Consequently I am installing a length of Aeroquip -4 hose and two male-to-male -4 fittings to allow me to re-route the hose away from the turbo and also to remove the stupid connector.

Doing this at the weekend so will try to take some pictures.......