Drag Racing Tech - Gains from ditching tru trac and going spool?

Putting in a light weight spool and taking out the tru trac. Just curious to what gains I might see at the tire and at the track.

Approximately 50# rotating mass..........maybe up to .03 ????

I will also recommend that you keep an eye on lugnut torque. They will come loose once in a while due to the back and forth twisting action of the axles.

I had a gear driven limited slip on my black street/turbo car.

I have a spool on my new car.

It isn't an apples to apples comparison at all, but the spool is noticeable in reverse with the wheels turned.

I couldn't give you an honest answer at the track aside from both tires spin when it doesn't hook!:)

Nothing lol... I did this swap last year and other then shedding some weight and insuring both tires are spinning, no noticable gains for me.

peace of mind knowing that it's not going to break.

If your tru trac is not slipping, you will see no difference. If you are wheelstanding the spool will keep the car straighter. Thats about it.

peace of mind knowing that it's not going to break.

This is why I switched.

Approximately 50# rotating mass..........maybe up to .03 ????

I will also recommend that you keep an eye on lugnut torque. They will come loose once in a while due to the back and forth twisting action of the axles.

50lbs??? U sure about that?

I did the swap on mine, and saw no difference. I pulled it down to do a gear change, and found metal. The Detroit try trac was eating itself up, but not enough to make the car act up. I ordered a Moser steel spool. They advised against the aluminum one. Said the splines wear out faster. Witch makes sense.

Night and day difference. Simply because now you can make successful runs, and not BREAK THE TRU CRAP :drive: :nod:

Night and day difference. Simply because now you can make successful runs, and not BREAK THE TRU CRAP :drive: :nod:

I just put a tru crap in my 9" on the vette :jest:
I ran 1.3 60's all day on my 12 bolt posi-I figured how bad could it be?
Now I know-thx JL :jest:

50lbs??? U sure about that?

more or less

I only notice mine now when I try and turn, especially in reverse. Make sure your rear tires are the same roll out or within 1/2" of each other. The M/T's I just got are just over 3/4 off and the car is wanting to pull, I'm trying to stretch the smaller one this weekend.

Night and day difference. Simply because now you can make successful runs, and not BREAK THE TRU CRAP :drive: :nod:

this sounds about right

I didnt think it would be much of a gain, but still help in the long run. I figured maybe .05ish and 5-10rwhp increase. Im really doing it to make sure the car stays straight and doesnt break.

Ive heard as much as 15+ rwhp.

Yea true trac is junk,spool and the peice of mind knowing it can handle abuse.

Tek, an old school eaton was a lot better then the tru junk.... At least those were rebuildable

Tek, an old school eaton was a lot better then the tru junk.... At least those were rebuildable

Lol-well I'll see how far I can push it-great thing about 3rd members-few bolts and it's gone so if its really an issue for me I can always keep an additional 3rd member with a spool and swap it in for track days. :nod:

I was (stuck) running 11.1x 11.25ish for months, same setup for almost 2 years worked it down form mid/high11's. Truetrac was I think acting up. changed it out to a spool (same gears and tires) saved 33.8pounds, The diffs, diff lol weight (s60) And my stock 60K mile rear shocks for some used summit 3ways from a local. When 10.8x 1st past, a week later (just put the spool in I think was the day before) It was getting fall time and the air was better, but it was still during the daytime. But not was comparing 90* air 150 track temp, 2800+ DA in AUG daytime. to 50* oct night 500DA.
I was really hopping for just a 10.99 was shocked to see it running 10.8x. I remember too, on the street car car felt slower with the spool, And I normally dont trust how the car feels (as in this case) After pulling some gears I didn't have to steer the car as much, it wasn't as wild (fun?) it drove straighter. The big ET pickup makes since, the shortest distance between 2 points is a strait line :) I dont know if everyone will see a result like that, but thats really how it went for me

true track history
http://www.ls1tech.com/forums/drag-racing-tech/1180194-m6-truetrac-roll-call-update-spool-truecrap.html

times running at the track (I had something like 25-35 passes between 11.25 and 11.11)
http://ls1tech.com/forums/drag-racing-results/1142871-cam-only-m6-stuck-11-1s.html

After going to spool- air was alot better then I thought but not 3-4 tenths better.
http://ls1tech.com/forums/drag-racing-results/1190529-cam-only-na-m6-10-842-127-5-a.html

Wow thats good to hear! I also have a S60 so it will basically be the same swap.

Mark I don't know how much power the Bette has, or if it has a solid axle or a 9 inch IRS center, but if it's hot good power, I would seriously think about ditching the try junk now before it's broken, new unused parts sell a lot better then broken used ones :)

Mark I don't know how much power the Bette has, or if it has a solid axle or a 9 inch IRS center, but if it's hot good power, I would seriously think about ditching the try junk now before it's broken, new unused parts sell a lot better then broken used ones :)

He mean't Tru Junk.

GOD darn auto correct!!!

:judge:

true track history
http://www.ls1tech.com/forums/drag-racing-tech/1180194-m6-truetrac-roll-call-update-spool-truecrap.html

times running at the track (I had something like 25-35 passes between 11.25 and 11.11)
http://ls1tech.com/forums/drag-racing-results/1142871-cam-only-m6-stuck-11-1s.html

After going to spool- air was alot better then I thought but not 3-4 tenths better.
http://ls1tech.com/forums/drag-racing-results/1190529-cam-only-na-m6-10-842-127-5-a.html

I read the thread-no one wrote about breaking a 35 spline tru track set up-which is what I have in my 9" (solid rear JL)
I'll be pushing around 750 fwhp-I'm gonna do a search on YB, maybe post a thread and see what success-failure others have had.
I really dont want to have a spool full time in the car-I may look into a 2nd 3rd member with a spool for race days if that will work. we'll see.

Race car parts ='s your car! lol Stop bein a Sally, sack up and put a spool in that bitch!

Me?? Or Tek?? I already have the spool just waiting for my date with Speedinc to install it.

Lol :jest:
I think I've earned the right not to be called a Sally :nod:
Just cause I wanna do something different doesn't mean I wont cut a light on you on raceday. ;)

You AC, lol. Running a locker these days is like asking if you should put a converter in your car or not!! Your car is ready for a spool! :)

lol Ya the spool is sitting on the table, with a new gear and install kit. Car goes into Speed on the 4th to finish the tune and install the parts. Gears are one thing I dont want to fool with in the garage.

The 2 nd 3 rd member will work, pull axles, unbolt and swap out, just the cost of fluid, a gasket/ silicone and your time, then you can run the right gear for the track and have it drive nice. That gets my vote...

The 2 nd 3 rd member will work, pull axles, unbolt and swap out, just the cost of fluid, a gasket/ silicone and your time, then you can run the right gear for the track and have it drive nice. That gets my vote...

Supposedly guys can do the swap in about 45 min but most guys on YB say between an hour to hour and a 1/2 realistically-which still isn't bad. Think you can re use the fluid as well.

I dont see why you couldnt reuse the fluids if its clean. An Extra 3rd member is the one reason I wish I had a 9" over the S60. Changing gears/diffs for tire changes etc would be way easier.

Probably can reuse the fluid as long as you don't get amy pieces of slilcone or gasket in it when you swap the center section.

45 minutes sounds a little agressive, unless you can get to it from inside the car. I'd say it's a 90 minute job, on jackstands if all the bolts are easy to get to. Maybe a little less on a lift, or a little more if you're not killing yourself. For sure doable in an afternoon regardless, while you're under the car, change the oil, nut and bolt all the suspension, etc.

-I may look into a 2nd 3rd member with a spool for race days if that will work. we'll see.

You used to complain about changing plugs each time you went to the track.
I can't wait to watch you swap out 3rd members. :jest::jest::jest:

those guys changing them in 45 minutes probably have a removable tunnel and dont have to jockey a torque arm out of there either. i have had mine apart many times but never have been able to do it in 45 minutes and thats on a lift not on jackstands.

You used to complain about changing plugs each time you went to the track.
I can't wait to watch you swap out 3rd members. :jest::jest::jest:

This coming from a guy who kicks field goals with fuel jugs in his trailor :jest:
As long as YOU don't jack up my car, u know what I mean ;) I'll live thru it. :nod:

I haven't even broke the tru crap yet and I'm getting shit :jest:

subhumanz-this is on a 4 link c3 vette-no TA and plenty of room to get to the bolts if need be.

Rick (firehawk) I can't wait to watch you change 600 nitrous jets between rounds :jest:

This is one of house things your gona spend the money and get both 3rd members setups to have a bad ass track setup, that you street drive. And your gona end up just leaving the spool in all the time. At 1st few short drives a few streets over on the spool, turns into driving it across town, and its fine. And your not gona deal with changing the 3rd member, and just drive on the spool and save the 2 hours working on the car. Doing something BS like that, its not a cool and get old FAST. Its not a new/better/lighter part. Its that 3rd members you changed 5 days ago for the 2nd time, and will have to put the spool back in. In 3 days, thurs after work (quick so you can be somwhere at 9), to get the the track friday after work....
\
And the spool dosnt really wear out the tires that much that matters. Somone running $600 315/30s DRs on 18' ZO6 rims is gona notice they get scuffed, and bind up in parking lots. And has a car that traps 113, they go to the track 3 times a year, and not like the spool, Like your thinking you hear about.
But street driving a 130+ trap car, you beat the shit out the the car when you street drive it. And do the rolling 20-80 burnouts just to show off, the spool isn't gona cut 10K miles off the tires that your getting 40K out of or anything like that. Your getting new street DR ever summer anyway
Just like taking the front swaybar off. "I can put it back on for street driving" how many times to people move it around there garage, or move and take it with them. And realize its been 1-3 years, toss that thing out : ) Same with taking a endlink off you a anti roll bar, you talk about doing it. But no one really dose it, its a myth. haha

is that wheelie bars :confused:

studd-u talkin to a guy who's drove around with a spool, wheelie bars etc and THAT gets old too. ;)
It's also not the tires that's the most concern, it's the shark finning of the axle's from street driving on a spool. The type of shit that when it breaks it leaves your "street" car stuck at some bbq with your girl :jest:
If I had 2 3rd members would I change them out ALL the time-of course not. If it was gonna be 2 weeks till my next race and I wanted to take my wife away for the weekend in the vette-yes I would change it out.
BUT I'm not doing SHIT :) until I break a 35 spline posi set up-which still no one has chimed in that they broke it yet.

Are you going to run radials on the car? If so you'll break one quickly. First time the car gets some tire shake... it will break.

This coming from a guy who kicks field goals with fuel jugs in his trailor :jest:
As long as YOU don't jack up my car, u know what I mean ;) I'll live thru it. :nod:

That fuel jug deserved it. Besides, it was one of yours. :jest:

I won't ever touch that :turd: YOU call a jack or those :swing: stands ever again. We're lucky to be alive. :bomb:

That fuel jug deserved it. Besides, it was one of yours. :jest:

I won't ever touch that :turd: YOU call a jack or those :swing: stands ever again. We're lucky to be alive. :bomb:

:jest: :jest: How's the elbow?? :rotflmao:

Ok I didnt dyno with and without the tru trac but I did weigh it after the swap. The new strange light weight spool was 15lb shipped and the tru trac with ring gear still on it was 58lbs. Thats gotta be worth something.


Also the spool is not nearly as bad on the street as one would think. You actually cant even tell unless its a super tight turn.

50lbs??? U sure about that?

He was right. I weighed that heavy ass thing. lol

He was right. I weighed that heavy ass thing. lol

No shit? Dayum.
Just remember to check your axles every now and then-mine were shark finned pretty good with not that many street miles on it.
Thanks for the info. :nod:

Yes, they weigh that much, got my other one out from years ago. It sucked moving. WHen you have atypical tru trac issues running a spool maybe become a pleasure.

Like I said......keep an eye on your lugnut torque.