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Tremec Magnum XL swap

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I'm looking at getting the kit from JPC. Just wanted to see if anyone recommends doing anything else while doing this.

I am going with the 2.97 gearing, mcleod RXT, lightened flywheel, new slave, CJ pulse ring, crank position sensor, and 4.10 rear gear.

Just wanted to see if there were any suggestions out there from those that have already done this swap.
 
Why are you changing?
 

Mad Hatter

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NFSBOSS said:
Why are you changing?

Good question, after the blowfish bracket was installed I stopped looking at the Tremec XL kit. Now with the MGW race shifter out as well, seems to be no point unless you are going to monster HP. The Tremec ratios are all wrong track as well. If it was closer to the MT82 ratios then maybe....

Consensus seems to be that MT82 is not a bad tranny, but the OEM shifter is a POS and Ford should be ashamed for building it. The OEM shifter made me eat two transmissions....so am a little bitter about it (rant)
 
12coBoss said:
I'm looking at getting the kit from JPC. Just wanted to see if anyone recommends doing anything else while doing this.

I am going with the 2.97 gearing, mcleod RXT, lightened flywheel, new slave, CJ pulse ring, crank position sensor, and 4.10 rear gear.

Just wanted to see if there were any suggestions out there from those that have already done this swap.

That's the setup I've been running for 2 years except I went with the close ratio 2.66 version of the trans with the 4.10s. The mt-82 has weak synchro forks that wear or warp at high rpm shifts is what I've been told.
 

Mad Hatter

Gotta go Faster
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From sad expensive experience..... I can say that the trouble is the remote shifter. Changing the forks is a good idea but the nitty gritty is that the remote shifter really ruins what seems to be a decent box. After installing a Blowfish shifter brace, my shifting problems went away. Now the MGW race shifter also looks very good as well. I was almost ready to get the XL but glad I held back.
 
I've got the Tremec Magnum XL with the 2.66 gears as well with the 4.10 gears. I also had them change the Over Drive Cluster to the .80/.63 one, vice the one it comes with. As far as the clutch/flywheel, why not try the Exedy Hyper Single disk setup?
 
wwilde001 said:
I've got the Tremec Magnum XL with the 2.66 gears as well with the 4.10 gears. I also had them change the Over Drive Cluster to the .80/.63 one, vice the one it comes with. As far as the clutch/flywheel, why not try the Exedy Hyper Single disk setup?
Yeah I forgot to mention I swapped 5th to a .86 and had Rockland put carbon synchros in it while they had it apart.
 
898
544
I think it is a combination of parts not suited to the application. The clutch is the biggest weak link followed by the remote shifter and then some of the internal parts such as the shift stop and forks.
 
Mad Hatter said:
Good question, after the blowfish bracket was installed I stopped looking at the Tremec XL kit. Now with the MGW race shifter out as well, seems to be no point unless you are going to monster HP. The Tremec ratios are all wrong track as well. If it was closer to the MT82 ratios then maybe....

Consensus seems to be that MT82 is not a bad tranny, but the OEM shifter is a POS and Ford should be ashamed for building it. The OEM shifter made me eat two transmissions....so am a little bitter about it (rant)

Main issue is i have had to many issues. Once the car gets warm after a couple laps it does not want to shift into 4th or 5th gear. Shifts extremely hard, I am shifting around 7800 rpm. Since my last track event it does not always want to go into 1st gear while sitting still. It will go in half way but not all the way. Just tired of trying to find fixes for it, i have already the MGW, stainless clutch line, swapped fluid, just ready to change it out.

i do like the gearing in the MT82, but at the end of the straights that I run at I am out of gear. I could shift but will only be for a second or two so not worth it. So maybe the new gearing will help me out in those cases.

Why go with RXT over Exedy? Haven't heard of any issues with the RXT, I guess I haven't heard anything bad about the Exedy either, but Mcleod is more popular.
 
147
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DGRacing said:
Yeah I forgot to mention I swapped 5th to a .86 and had Rockland put carbon synchros in it while they had it apart.

If you have a 2.66, I don't think it is possible to have an .86 fifth. Better check on that.
 
Didnt want to start a new thread on this topic.. I have a magnum XL, car was previously supercharged and now back to an N/A Cobra Jet setup. I am thinking to go with 4.56's, currently have 3.73's and it lacks gear i feel. Looking at ratio calculations, i feel 4.56's would be perfect for the road course/auto x which is the primary use of my car and also perfect for drag racing when i do occasional visit the track. with the long 6th gear i dont worry about the highway. What do you all think? I suppose an diff cooler will become a must! Any issues other than that?
 

Fabman

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I have the Magnum XL 297 trans.
Excellent trans though I wish I would have gotten the 266 instead.
Mine is to wide ratio for road courses and even with 4:10 gears, 6th gear is never used.
 
I have the Magnum XL 297 trans.
Excellent trans though I wish I would have gotten the 266 instead.
Mine is to wide ratio for road courses and even with 4:10 gears, 6th gear is never used.

I dont think the 266 would have helped, 5th gear is nicer, but u can have that swapped into the 297. I like the fact 6th is the serious overdrive, only for the highway gear. But i get your point. I think im going to be trying my luck with the extreme - a 4.56. Will then take it from there, maybe move down to a 4.10 or 4.30 if i didnt like it or had serious heat issues. Im still on the clutch diff and dont think ill do the torsen yet.
 

Fabman

Dances with Racecars
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Pleasanton: 1/2 way between Sonoma and Laguna Seca
I dont think the 266 would have helped, 5th gear is nicer, but u can have that swapped into the 297. I like the fact 6th is the serious overdrive, only for the highway gear. But i get your point. I think im going to be trying my luck with the extreme - a 4.56. Will then take it from there, maybe move down to a 4.10 or 4.30 if i didnt like it or had serious heat issues. Im still on the clutch diff and dont think ill do the torsen yet.
that step from 3rd to 4th is a loooong one....
 
898
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Just keep in mind that 4:56 gears, even from FRPP, will not drop into a torsen rear end. The ring gear is to thick to allow the pillow block to slide back into the differential. If you want to run a 4:56 with a torsen, you will need a custom spacer. They are available from Blowfish Racing:

https://www.blowfishracing.com/drivetrain/114-88-ford-torsen-spacer-block-set.html

A 4:10 gear will fit without issue. I am not sure about the 4:30, but I suspect it might fit since it was occasionally run in PWC cars.
 

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
Just keep in mind that 4:56 gears, even from FRPP, will not drop into a torsen rear end. The ring gear is to thick to allow the pillow block to slide back into the differential. If you want to run a 4:56 with a torsen, you will need a custom spacer. They are available from Blowfish Racing:

https://www.blowfishracing.com/drivetrain/114-88-ford-torsen-spacer-block-set.html

A 4:10 gear will fit without issue. I am not sure about the 4:30, but I suspect it might fit since it was occasionally run in PWC cars.
This is what i love about this site, no matter what the subject, somebody knows the right answer.
 

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
Maybe even TWO people will know the right answer. LOL.
 

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