how much punishment can a M5R2 take?

fastime

Registered User
I recently purchaced a '90 supercoupe drivetrain to drop into my 86 mustang. I plan on freshing the motor, porting the heads, doing the MagnaPort II and Blower Re-Build Package from www.magnumpowers.com , long tube headers and 4:10's ... my worry is that this tranny won't take 4 grand launches long .. any input? THANKS!
 
here is my m5r2 story, hope it helps

Bought my 92 about 3 1/2 years ago with 13,000 on it, was like a brand new car and loved it. I got it not knowing how to drive a stick but caught on quick(had no choice) Anyway when i learned how to "powershit" i really started to have fun with the car. Until about 6 months after i had it i powershifted into second and missed it, from then on it would grind into second. From there eventually every single gear in the tranny would grind.(all in the duration of about 2 years) Nothing really broke in it and left me so i couldnt shift into and out of gear but it would always grind (synchros/gears). Year and a half ago right before christmas the tranny finally took the final crap and was stuck in third. After that got a tranny for 600 bucks that was supposed to have been "tested" but when i had that put in third was grinding also. That lasted till about 6 months ago and then second started to grind again. Still driveable, still powershift at least a dozen times a weak. I think ppl say that the m5r2 can handle more torque then a regular t5 but i will leave that one for the pros. But i can say that both trannys took a lot of punishment from me. For the amount of torque sc's put out you should be careful with how much you beat on it and the rpm's you mormally shift at. But when it starts to go and you dont have a crapload of money for a used/new one or to rebuild, which gear prices i have seen from mazda are freakin rediculious, i would go easy on it. Sorry, a bit long but my tranny has been the only draw back to my car. Since a havent been able to shift it the way i want to for 3 years.
 
Unless I missed something here, you have a stang wanting to do a sc engine. Use a mustang based t5 or better such 5 spd. Every 5spd owner hates their m5r2 and yearns for the day they will make a t5/borg warner/richmond compliant for it. Also, your shifter will sit about 6 inches further back if you use the m5r2, so get creative with a sallzaw or a jig, and start cutting. If anything, sell the m5r2 for about 300-500, assuming it's in great shape, sell off current tranny from car, then buy a better performance based t5, and then, launch at about 2500 if your on street tires, 4000 if on drag radials/slicks. Just my .02 of what i'd do. M5R2's are garbage when beaten on. They only used them because they would hold the torque of the engine.
 
I just had my M5R2 rebuilt with brass synchros. When its cold it wants to grind 2nd if you don't JAM it into 2nd. Once you drive it for like 10 minutes its ok. If I shift to 3rd its ok, but if I speed shift it 3rd will grind. I hate it, and I want an AOD but I like having a 5-speed and AOD SC so I might just leave it and park it when I get my other car done.
 
If you're gunning for the strip put an auto in it with a higher stall, maybe even a C4 for no more worries but also no OD. You can get an AOD that can handle a beating as long as you don't try to beat on it in OD.
 
I put my 5 speed through a lot of pain and it takes it real well, the only thing is that if I rev it up too much in 1rst gear it won't let me shift into 2nd fast enough, but after second I can shift it like a dream. 2nd and 3rd pull like a MF! I got 2.73 on the back and I can still take a 1996 mustang gt from stop light to stop light.
Maybe I'm just a bad a#$ driver:D
 
If you use an M5r2, you do not want to use 4:10 gears, or you will go no where fast. The M5R2 is geared much more steeply than the T-5, the 4:10's are way way too much for an M5R2. Go with a
T-5 or T56. If you do keep the M5R2, go with a 3:27 gear in the rear.
 
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