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Has anyone done the Magnum XL swap and regretted it?

438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Just like the title says. Has anyone done the Tremec Magnum XL swap and later wished they would have kept their MT82? I was happy with my MT82 until having it rebuilt while it was out for a clutch swap. The rebuild made it through the recommended 1,000 break in miles and 1 track day at NCM then 4th gear shattered on the street soon after, basically destroying everything inside. My choices at this time are a Calime stage 3 or the Magnum XL swap. Money is about the same with the exception of needing a new drive shaft. Since my Calimer stage 2 blew up so quickly I am reluctant to have him build me another transmission.
 
823
1,269
Exp. Type
Time Attack
Exp. Level
3-5 Years
SoCal
I had issues with the Tremec, but as a result of using Royal Purple Synchromax after starting out with the Tremec HP MTF. Availability of the Tremec fluid has been hit or miss, so I’ve made it a point to always have back stock now. But even after this setback, I don’t regret for a minute making the change. Stick with one type of fluid and don’t look back.

Also, take your time and research the proper spacing on the slave cylinder, which will be dependent on your clutch choice. I replicated the setup that Kohr used in their race cars, which is Exedy Hypersingle, Kohr aluminum spacer and GT500 slave cylinder. I just recently switched to the GT500 master as well - didn’t realize they were different and now I can say the entire system works perfectly.
 
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438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Thank you for sharing our experience. I did not realize the Magnum XL was so sensitive to fluid choice. I saw where Tremec recommended Dextron III, which I thought was awful thin for a manual.

I have a basically new Mantic twin disk and plan to keep it. I am sending it back to Mantic and they are going to fit it with 26 spline disks and adjust the fingers for the Magnum XL if that is the route I choose. If not, they will fit it for 26 spline disks for the Calimer stage 3 MT82 with 26 spline input shaft. Calimer said he wouldn't sell me another 23 spline shaft after mine twisted.
 
438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
In the same spirit of this thread I would like to hear the good and bad from people who went the Calimer stag 3 route. I am trying to gather as much info as possible before making my final decision.
 
5,506
6,459
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
In the same spirit of this thread I would like to hear the good and bad from people who went the Calimer stag 3 route. I am trying to gather as much info as possible before making my final decision.
While I didn't have an MT82, my Magnum XL has been stellar. In fact I've had 2 of them. A wide ratio box and a close ratio box.
I originally used Amsoil ATF but when I went to the close ratio box I used the Tremec fluid and boy was that terrible. Would not shift at high rpm....at all.
I put Amsoil back in and it was like magic. Clean shifts up to 8200k. Crazy how fluid makes that much of a difference, but it does.
 
438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
While I didn't have an MT82, my Magnum XL has been stellar. In fact I've had 2 of them. A wide ratio box and a close ratio box.
I originally used Amsoil ATF but when I went to the close ratio box I used the Tremec fluid and boy was that terrible. Would not shift at high rpm....at all.
I put Amsoil back in and it was like magic. Clean shifts up to 8200k. Crazy how fluid makes that much of a difference, but it does.
Why have you had 2 of them? Did one have problems or was it a gear spacing issue? Also, what gears are you running in the rear?
 
5,506
6,459
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Why have you had 2 of them? Did one have problems or was it a gear spacing issue? Also, what gears are you running in the rear?
Both have been trouble free.
I used a wide ratio with the super charged 3v as the redline was only 7400k but that big power would pull the wider gear spread no problem.
I went to the close ratio for the Coyote as it has a redline of 8200k but way less power/torque to pull the gear, plus the 3rd to 4th gear spread works perfect with my 4:10 rear end for the tracks I run.
 
438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Both have been trouble free.
I used a wide ratio with the super charged 3v as the redline was only 7400k but that big power would pull the wider gear spread no problem.
I went to the close ratio for the Coyote as it has a redline of 8200k but way less power/torque to pull the gear, plus the 3rd to 4th gear spread works perfect with my 4:10 rear end for the tracks I run.
That is good to hear. I have run the numbers and the close ratio with either a 3.90 or 4.10 rear looks like the way to go for me as well. I was worried about the 3-4 spread on the wide ratio, unfortunately right now I am only finding the wide ration in stock. I may have to wait awhile until the close ratios start shipping again.
 
5,506
6,459
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
That is good to hear. I have run the numbers and the close ratio with either a 3.90 or 4.10 rear looks like the way to go for me as well. I was worried about the 3-4 spread on the wide ratio, unfortunately right now I am only finding the wide ration in stock. I may have to wait awhile until the close ratios start shipping again.
Get the one Kohr has. Its the close ratio 1-4 with the close ratio 5-6 from the 2:97 low trans.
Best of both worlds.
 
438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Get the one Kohr has. Its the close ratio 1-4 with the close ratio 5-6 from the 2:97 low trans.
Best of both worlds.
What I am finding is that Tremec is currently offering 2 versions. Both have the same 4,5, and 6 as follows:

1658022955460.png

I am looking at the 2.66 first gear. Gears 1-4 are about the same as 2-5 in the MT82, which are the gears I use on track.
 
5,506
6,459
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
What I am finding is that Tremec is currently offering 2 versions. Both have the same 4,5, and 6 as follows:

View attachment 77414

I am looking at the 2.66 first gear. Gears 1-4 are about the same as 2-5 in the MT82, which are the gears I use on track.
Okay, that's new then....when I bought my first Magnum the 2:66 trans had a stupid wide ratio 4-5-6.
 
438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Okay, that's new then....when I bought my first Magnum the 2:66 trans had a stupid wide ratio 4-5-6.
Yeah, they used to have a .74 and .5 overdrive clusters. They changed it. It sounds like most people were wanting the close ratio with the .8 and .63 overdrive cluster and shops were changing it for people on new transmissions. I have found a couple of the 2.97 first gear models in stock, but none of the 2.66 model. The distributors I have talked with are expecting some in the next couple of weeks.
 
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438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
What I am finding is that Tremec is currently offering 2 versions. Both have the same 4,5, and 6 as follows:

View attachment 77414

I am looking at the 2.66 first gear. Gears 1-4 are about the same as 2-5 in the MT82, which are the gears I use on track.
I miskeyed the 6th gear ratio. It is actually .63 on both.
 
438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Worked perfectly for me.
Thank you for the feedback. I can try the stock shifter and if I don't like it I can always change it out later. It looks like the Magnum XL is going to be the way to go. I am trying to round up everything I need, so I don't run into any delays during the install waiting on additional parts. So far it sounds like the close ratio Magnum XL swap kit, new drive shaft, the electrical connections and the Quicktime RM-130 alignment plate. The speedometer sounds like it can be corrected by my tuner so I won't need an electronic converter box. I will most likely need a gear swap, but it can wait until I was going to swap the trac loc for a thorsen T2R this winter. Is there anything I am missing?
 
5,506
6,459
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Thank you for the feedback. I can try the stock shifter and if I don't like it I can always change it out later. It looks like the Magnum XL is going to be the way to go. I am trying to round up everything I need, so I don't run into any delays during the install waiting on additional parts. So far it sounds like the close ratio Magnum XL swap kit, new drive shaft, the electrical connections and the Quicktime RM-130 alignment plate. The speedometer sounds like it can be corrected by my tuner so I won't need an electronic converter box. I will most likely need a gear swap, but it can wait until I was going to swap the trac loc for a thorsen T2R this winter. Is there anything I am missing?
A good clutch. Exedy hyper single is a go to for a lot of us.
 
438
381
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I have a Mantic 9000 series twin disk that I put in with the Calimer Stage 2 MT82 in March. I plan to keep it. I sent it back to Mantic yesterday to switch out the 23 spline disks for 26 splines. I forgot to mention that in the above post.
 
823
1,269
Exp. Type
Time Attack
Exp. Level
3-5 Years
SoCal
I have a Mantic 9000 series twin disk that I put in with the Calimer Stage 2 MT82 in March. I plan to keep it. I sent it back to Mantic yesterday to switch out the 23 spline disks for 26 splines. I forgot to mention that in the above post.
Were you using the stock slave cylinder with this clutch on the MT82? With yours being a 2011, there may have been a thin shim under the CSC?
 

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