Drivetrain T56 Magnum Install '89 Fox

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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I agree with everything 'cept the t5 being unreliable, I have been abusing my t5 for about 50k miles. No track stuff but I'm not afraid to dump the clutch from a roll, I'm also smart enough not to use sticky tires. Just know it's limits.
 
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FastDriver

My dad had a bra
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Who cares about a dyno number. We only use it to tune. Say the T5 is more efficient but it's slower at the track due to wide gear. What good is this information?

We all modify for different reasons. T56 shifts better, T5 is cheaper, T5 is great for wide power bands, T56 will handle way more power, T5 is unreliable etc.

So even if there was, and probably is a slight loss. The T5 and T56 Magnum close ratio have very different gear ratios. So a back to back comparison is not realistic. Some engines hate the big rpm drop between gears, some don't care.
Obviously, I care. Suit yourself if you don't use a dyno to compare the pros and cons of parts that you might choose between, but I do, and so do many others. What good is the information? Well, for starters, this is my hobby, and I ENJOY obsessing over the details. I enjoy optimizing my combination to get it to the goldilocks standard for me - just right. Transmissions are also a big amount of money to spend. So, I appreciate a full understanding of the pros and cons before making my decision or advising others to make the right decision.

It's a bigger deal to many than you're making it out to be. In fact, I'd wager that @Mustang5L5 is considering this very topic, if he hasn't already come to a conclusion on the matter. Further, aftermarket T5s can be made plenty stout for about 95% of the enthusiast market out there that'll be happy at the limit of the stock block (and beyond). Further that that, 4th gear is the same in both transmissions and the first 3 are variable to your liking when you're smart about which internals you want to use. So, your implication that T5s and T56s are meant for different powerbands overlooks quite a bit of the option available, especially when you're doing custom gearing, as you would if you're trying to make 500+ ft-lbs through a T5 with some reliability.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
I get what Fast is say'n (I can call you Fast right?) and I read about a lot of builds, some stuff is actually built to abuse (love my Car Craft mag!) I notice a fair amount of t5 stuff, but the shop builds are (most) always talking t56 and more so 3550, I'm curious to know the difference in hp between them. Like years ago when a 9" was compared to the 8 .8 for parasitic loss.
In reality? I'm just glad mine starts and goes when I get behind the wheel.
 
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Rt jam

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Oct 17, 2015
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You are taking the comment out of context. Who cares means ONLY as a dyno number, this difference is irrelevant. So if a T56 shows a loss. Most will still use it due to gear ratio choices, it shifts better and it's stronger. Too many other variable.
For a single comparable part like a rear axle. If you have 2 same ratios, same weight, same cost. Then yes, the more efficient one will get the go ahead.

As for reliable. Sure they are. I had a stock 88 LX 5.0 that went 400,000kms and sold as still a fully functioning car that shifted great. I trust that trans.

Compared to a T56, no, they are not AS reliable even compared to Astro or G Force.
 
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