Drivetrain T56 Magnum Install '89 Fox

Rt jam said:

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.

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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.

I'll give ya a hint... I once said My dad had a bra on his '89 Fox body... and the rest is history.

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.

Rt jam said:

Excellent write up Chill347.

I also just did the T5 to T56 Magnum swap. My kit was from D and D Performance. Came with Quicktime Bellhousing, driveshaft, crossmember, speedometer cable, shifter and the close ratio like yours.

I had the same problem with long tube headers trying to be in the same space as the release fork. I used a McLeod hydraulic release to resolve.

No floor or shifter hole clearance required but I had to cut off the same ear off the passenger side. When the cut piece fell to the floor and I saw a green paint line right where I cut and an X on the offending piece. I figured it was marked to cut but nobody cut it.

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I also bought the same kit from D&D Performance. I have a question for you since I haven't been able to get a response back from D&D. Don suggested I set the pivot ball stud at 1.325" from the front cover. Is this measurement to the flat side of the ball or to the very tip? I want to set this correct before I make the front cover mods.