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Has anyone done the Magnum XL swap and regretted it?

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Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Good grief!!! What a pain in the butt. Did you buy the tranny as part of a kit? Or all by individual parts? I get confused, when the say close ratio XL is that the 2.97 or the 2.66?
 
1,119
1,110
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Good grief!!! What a pain in the butt. Did you buy the tranny as part of a kit? Or all by individual parts? I get confused, when the say close ratio XL is that the 2.97 or the 2.66?
I bought the swap kit with the trans, bell housing, block plate, and cross member from Modern Driveline. They also supplied the wiring harnesses. I had Mantic re-disk by twin disk clutch since it had less than 1200 miles on it. They sent the wrong alignment tool and I didn't notice the .009 difference in the pilot end diameter. Modern didn't have drive shafts in stock. I sourced the driveshaft from ShaftMasters since it was available and was priced better.
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Good grief!!! What a pain in the butt. Did you buy the tranny as part of a kit? Or all by individual parts? I get confused, when the say close ratio XL is that the 2.97 or the 2.66?
2.66 is close ratio
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
I bought the swap kit with the trans, bell housing, block plate, and cross member from Modern Driveline. They also supplied the wiring harnesses. I had Mantic re-disk by twin disk clutch since it had less than 1200 miles on it. They sent the wrong alignment tool and I didn't notice the .009 difference in the pilot end diameter. Modern didn't have drive shafts in stock. I sourced the driveshaft from ShaftMasters since it was available and was priced better.
sounds like human error is plaguing you, sometimes that happens. The trans is awesome and you will love it when everything finally comes together.
 
1,119
1,110
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I went to Michigan last weekend for a family event. I dropped the drive shaft off at Shaftmasters to be fixed. They had it fixed and on a FedEx truck Monday. It arrived Wednesday. I hope to have everything finished up this weekend.
 
1,119
1,110
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I made some progress.
The driveshaft is in, but my Steeda driveshaft loop will not fit with the Magnum xl
Exhaust is back on, but I have a small leak somewhere
Battery and tray are back in
Car is running and driving, but the console is still out. I need to find a keyed 12v power source for the reverse lock out switch. I was going to use the hot to the cigarette lighter plug, but it is always hot. Also, Modern Driveline sent me the wrong shift ball collar. Figures, since everyone else sent me something wrong, why not them too? They sent one for a 2008+ Mustang, not one for the Magnum XL. The threads are 12mm x 1.25mm instead of the 12mm x 1.75 used on the Magnum XL shift rod.

A couple things I learned:

The reverse lock out wiring harness that Modern sells is way too long. You need to cut off a couple of feet or coil it up inside the console. Also, the $35 plug and play reverse light switch extension does not plug into the 2011 and up harness. You still need to cut it and splice it. You are probably better off buying the $15 pigtail and extending the harness yourself. It doesn't take that much force to push past the springs in the reverse lock out. I don't think the control module is necessary, but I was told I needed it and have it, so I will use it.

The new clutch disks feel really good. Geoff at Mantic picked me out a couple 26 spline disks with a little more cushion than the 23 spline that I had. The clutch is much more stock like. It engages lower and isn't as harsh as the last go around.
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
I made some progress.
The driveshaft is in, but my Steeda driveshaft loop will not fit with the Magnum xl
Exhaust is back on, but I have a small leak somewhere
Battery and tray are back in
Car is running and driving, but the console is still out. I need to find a keyed 12v power source for the reverse lock out switch. I was going to use the hot to the cigarette lighter plug, but it is always hot. Also, Modern Driveline sent me the wrong shift ball collar. Figures, since everyone else sent me something wrong, why not them too? They sent one for a 2008+ Mustang, not one for the Magnum XL. The threads are 12mm x 1.25mm instead of the 12mm x 1.75 used on the Magnum XL shift rod.

A couple things I learned:

The reverse lock out wiring harness that Modern sells is way too long. You need to cut off a couple of feet or coil it up inside the console. Also, the $35 plug and play reverse light switch extension does not plug into the 2011 and up harness. You still need to cut it and splice it. You are probably better off buying the $15 pigtail and extending the harness yourself. It doesn't take that much force to push past the springs in the reverse lock out. I don't think the control module is necessary, but I was told I needed it and have it, so I will use it.

The new clutch disks feel really good. Geoff at Mantic picked me out a couple 26 spline disks with a little more cushion than the 23 spline that I had. The clutch is much more stock like. It engages lower and isn't as harsh as the last go around.
I didn't use the reverse lockout switch either.....totally not necessary IMHO.
 
16
18
Exp. Type
HPDE
Exp. Level
10-20 Years
Indiana
...so back to the beginning, what does Calimer say about the failed trans? I don't understand why a stock one would hold up and the stage 2 would fail so quickly. I feel that needs to be part of the discussion here as well. Obviously the Tremec is stronger but seems overkill for stock all motor coyote guys on a road course....
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
...so back to the beginning, what does Calimer say about the failed trans? I don't understand why a stock one would hold up and the stage 2 would fail so quickly. I feel that needs to be part of the discussion here as well. Obviously the Tremec is stronger but seems overkill for stock all motor coyote guys on a road course....
In my case it not the gears that fail in my stage 3, they all look fine. Its the syncro assembly teath that gets worn on the back of the gear. I don't do no-lift shifts, but maybe I am shifting to fast. Going to try slowing them down a tad and using a heavier tranny oil. From what I have seen so far, the XL seems to have a heavier duty syncro setup.

As far as Calimer responding, they answered my email right away and sent me 3rd and 4th forged gears right away.

An all motor coyote is still 580+hp to the flywheel, and an hour on the track going full tilt is pretty demanding on the transmission.
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
In my case it not the gears that fail in my stage 3, they all look fine. Its the syncro assembly teath that gets worn on the back of the gear. I don't do no-lift shifts, but maybe I am shifting to fast. Going to try slowing them down a tad and using a heavier tranny oil. From what I have seen so far, the XL seems to have a heavier duty syncro setup.

As far as Calimer responding, they answered my email right away and sent me 3rd and 4th forged gears right away.

An all motor coyote is still 580+hp to the flywheel, and an hour on the track going full tilt is pretty demanding on the transmission.
2 words: "Dog Rings". There, I said it.
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Yup! thats the main reason I think 2023 will be with a XL. Am very curious to see what the insides of your gearbox look like.
 

Fabman

Dances with Racecars
6,518
8,154
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Yup! thats the main reason I think 2023 will be with a XL. Am very curious to see what the insides of your gearbox look like.
Hell, I’ll never know. It will go to a shop to get modified. I’m not smart enough to do this sh!t. I just hold my foot to the floor and pull the lever.
 
16
18
Exp. Type
HPDE
Exp. Level
10-20 Years
Indiana
I have not built an MT82 yet but I've built my share of manual transmissions, certainly enough to be dangerous. I was wondering what was failing on these units. Lots of guys over on Mustang6G have Calimer MT82s behind blowers and all kinds of stuff and have decent luck with them. Over here is the only place I see them not holding up well. Sounds like it's not a maximum torque capacity issue, but it's a repeated shifting under extreme duty issue that's causing the failures?
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Yes thats about it. The Mt82 "improved" for the S550 a little bit, but is still a little delicate. The shop that helps me out with my car has about 15 modified Mustangs ranging from 430 to 900 rwhp. Generally speaking the manuals last about 4 to 6 trackdays..... Before something goes wrong. Then again the automatics dont last that much longer either... especially the 10 speed.

The first mt2 on my 2012 Boss had issues at 8000km (5000miles), that was on the highway shifting from 4th to 5th!! So they have improved since then... The OEM MT82 gets REALLY REALLY hot at the track. As in +300F. Cooling is a big issue as are the OEM clutches.
 
1,119
1,110
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
...so back to the beginning, what does Calimer say about the failed trans? I don't understand why a stock one would hold up and the stage 2 would fail so quickly. I feel that needs to be part of the discussion here as well. Obviously the Tremec is stronger but seems overkill for stock all motor coyote guys on a road course....
That was in one of the Calimer threads. The short version is Calimer does not stand behind his transmissions once installed. I was told point blank if you install it and back it out of the garage they sent you a good transmission. They may give you a day or two but after that it is something that you did. They even recommend a 1,000 easy break in miles before running the car, but if you do that in their mind it was a good transmission. They blame your clutch choice first (even it is one they are currently selling) and the driver next. They claim it was a high rpm missed shift that broke 4th gear. I was not in the car when it broke, but I know where it was being test driven and that isn't possible in that area. The only thing we can agree on is 4th gear broke. If a single missed shift will destroy their stage 2 build it is to fragile to be in the car in the first place. A stock MT82 would of held up better.
 
1,119
1,110
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I have not built an MT82 yet but I've built my share of manual transmissions, certainly enough to be dangerous. I was wondering what was failing on these units. Lots of guys over on Mustang6G have Calimer MT82s behind blowers and all kinds of stuff and have decent luck with them. Over here is the only place I see them not holding up well. Sounds like it's not a maximum torque capacity issue, but it's a repeated shifting under extreme duty issue that's causing the failures?
Calimer is a drag racer so are most of the guys over at Mustang 6g. Road course puts more stress on the trans since you have to shift up and down. The down shifting is probably harder on the trans than the upshift. Combine the constant high rpm shifting with 20-30 sessions or more on track and heat is a real factor that isn't an issue for high horsepower cars on a drag strip.
 
1,119
1,110
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I didn't use the reverse lockout switch either.....totally not necessary IMHO.
I agree that it really isn't necessary after test driving the car yesterday. I was told that it was necessary and have the control box and wiring harness already. My car is still a street car, so I am going to use it since I have it. It is mostly wired in. I just need to locate a switched 12v source to tap into for the hot. I'll let you know how much difference it makes once I finish it up.
 

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