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FastDriver · Feb 11, 2023

I loved the 4.10s in Black Jack when I could go to the strip on weekends. It was pretty useless in 1st on the street though. The T56 effectively makes 1st and last gear the equivalent of having 3.08s in the car, now.

Mustang5L5 · Feb 11, 2023

The 3.73s are a holdover from when the car was an AOD. General recommendation typically is 3.73 min for those cars, and it was perfect. However had the car been a 5-spd I would have gone 3.55s

Ive done the math and have a spreadsheet. This was something long in the running that if I ever had the opportunity to swap gears, I figured 3.27s would be the gear I would go with.

My 2003 GT had a 3.38 1st with the t3650 and came with 3.27s and I always thought it was the perfect gear. I realize the 4.6L revs higher but I absolutely loved how 1st felt on that car, and how 4th gear was on the highway. I had zero desire to change the gears on that car during my 6 years of owning it.

So, for me and my driving style and highway speeds, 3.27s will suit me fine.

I’m going to do the install myself. It’s something I want to try, I have the correct tools and I think I’m capable of getting it done. I

bird_dog0347 · Feb 11, 2023

Gear it towards the application you will use it in, sounds like the 3.27 will be good for you. I did 3.55's on my car when it had the T5 and 1st was pretty useless, I will wait and see how I like it with the 4.6 and the T56 though, I haven't driven a Terminator but assume it will be like those were stock. Might as well check your TQ boxes while it's out.

FastDriver · Feb 11, 2023

Yep. You've definitely got this!

Mustang5L5 · Feb 11, 2023

bird_dog0347 said:
Might as well check your TQ boxes while it's out.

Did a quick inspect and all is fine. I never really launched the car hard during my course of ownership the last 25 years so I didn’t expect to see any tearing.

I might install a reinforcement kit though. Still debating it….

AeroCoupe · Feb 11, 2023

So the T5 in my Coupe is a 3.35 1st gear coupled with 3.73’s and 275/40R17’s.

On a hard dig it doesn’t feel like the car moves 100’ before I have to grab 2nd. Basically first gear is worthless. On the tollways the rpm’s are a little higher than I would like. With the 331 in the car I think I can change the rear gears but I don’t want to completely kill the acceleration out of the corners.

More and more I think a T56 is in the cars future but parting with the $$$ is the hard part.

Back to the more important stuff. Good news on the torque boxes.

Monkeybutt2000 · Feb 11, 2023

I loved the 3.73's with the 2.95 first in my old T-5z. I ran a 4.10 years ago with a 3.35 first,it was mostly a strip car though and had a hellacious launch. Street car though,yeah 3.27-3.31s.

Willybill32 · Feb 11, 2023

OK, maybe slightly off topic, but you guys are talking rear-end gear ratios in conjunction with 1st gear tranny ratios, so I’ll ask…

My ‘86 is in the shop for paint, totally torn down. I’m looking at putting it back together with a new TKX. New TKXs have either a 2.87 or 3.27 1st gear. I currently have 3.55s in the rear-end. Your thoughts on which 1st gear ratio is preferable?

2000xp8 · Feb 11, 2023

Willybill32 said:
OK, maybe slightly off topic, but you guys are talking rear-end gear ratios in conjunction with 1st gear tranny ratios, so I’ll ask…

My ‘86 is in the shop for paint, totally torn down. I’m looking at putting it back together with a new TKX. New TKXs have either a 2.87 or 3.27 1st gear. I currently have 3.55s in the rear-end. Your thoughts on which 1st gear ratio is preferable?

There are quite a few variables that go into it. Total power, power band, tire type, suspension upgrades.
A stock or close to stock setup, the 3.27 1st is an easy choice.

Willybill32 · Feb 11, 2023

2000xp8 said:
There are quite a few variables that go into it. Total power, power band, tire type, suspension upgrades.
A stock or close to stock setup, the 3.27 1st is an easy choice.

OK…my 5.0 has TFS TW 170 heads, E303 cam, Edelbrock Performer intake, roller rockers, headers, catted X-pipe, etc, and dyno’d at 314 HP/349 ft. lbs., so not too close to stock.

Bill

limp · Feb 11, 2023

I installed a TKX in my 83 that originally came with a SROD... I went through the same thing about first gear ( I knew I wanted the tallest 5thgear) when I ordered the 2.87 box......
My car will be a fun almost daily driver that I want to maybe take on some road trips....
Car has 3.50 rear gear with some "stock" 16" wheels and tires.... MOST ( like 98%) of the people who I made contact with were not happy with the 3.27 first gear boxes. The main complaint was they would have to almost immediatly shift into 2nd gear, usually before they even got out of the intersection...
I have not driven the car with the new drivetrain yet so I cannot tell you how mine is.....
In my opinion, these tall first gear boxes are meant to be coupled with a 3.07 or taller ( lower gear numerically) rear gears..... Throwbacks to the " gas mileage" era of cars after the gas shortages in 74-78/79...... When the manufacturers were trying to keep the revs down for fuel mileage with NON overdrive transmissions.... ...... The " modern " OD 5/6 speeds make the rear gear options much broader nowadays....
Hope this helps......

RaggedGT · Feb 11, 2023

Dibs on the 3.73’s….

Mustang5L5 · Feb 12, 2023

Pulled one side of the exhaust off. Easy as pie to do with no rear axle. Only did one side because I’m going to use the other side to help mock up my new exhaust so I want one on the car.

I also left the upper control arms bolted in place to help with understanding clearances and routing

Was going to try to reuse these tips, but now that I see them I don’t think I’ll get them out. I should just get the SS flowmaster tips.

That’s a 20 year old Flowmaster American Thunder cat-back with I believe the older super 40s.

Pulled my lower control arms up to clean up and regrease.

Now the bad news. With the exhaust and control arms out of the way, I discovered my inner subframe connector welds weren’t all that good and cracked. In my defense it was just hard to get in there. Fortunately the outer welds held fine. Now I know why I read in some places to drop the catback to get in there to weld the SFCs.

No big deal. I inspected all the other welds and they are fine. Now that I have access, I’ll fire up the welder and weld them properly now.

Mustang5L5 · Feb 12, 2023

Mock-up of the new mufflers. I gotta figure out the correct angle for the flow tubes. The flowmaster tubes are pretty straight, but these have a kick so not sure if it’s to lower the mufflers or raise them up a bit. I’ll have to wait until I put the exhaust tips on to see what works best.

I also may need to grab a set of SS exhaust hangers to tack onto the mufflers for some additional support.

I have to get some clamps as well.

The actual tips are in fine shape. What should I do here? Buy new SS tips or try and reuse these aluminumized tips? Hmm….

Mustang5L5 · Feb 12, 2023

And randomly, a supposed main landing gear axle off a WW2 bomber. Don’t ask how I came to possess it

I haven’t confirmed that it is yet, but the part numbers I’ve pulled off various pieces that were on it do suggest it is from something in that time period due to manufacture stamps and part number formats. Finding info is rather difficult as you can imagine.

I have some spacers and the axle nut as well. All seem period correct.

Mustang5L5 · Feb 12, 2023

Some pics of the axle. I redid this all back in 2009ish, so not a whole lot of miles but it did sit a lot.

I’ve got the MM braided lines on it, but not thrilled about how I did the lines on the axle. The bushings are still very pliable, so I likely won’t replaced those. The end bearings have low miles, but might as well replace the seals. Some paint and elbow grease will prob be the brunt of the work I do here. I don’t want to go tooooo crazy here. Could use some ARP hardware

Mustang5L5 · Feb 12, 2023

Ended up pulling the other side of the exhaust off. I needed access to pull the LCA off and to drill out the broken seat belt bolt plate.

Some might remember I snapped the head off the seatbelt bolt and couldn’t get this out. So I got my hands on some new plates and am just going to weld the new one in place

So now everything is wide open. I have clear access to those inside welds on the SFCs. My flowmasters were just in too close to get the right angle. Now I just need to prep and do some welding.

I’ll prob clean up some of the brackets under here. And replace the fuel filter.

Scope creep has set in.

Rdub6 · Feb 12, 2023

Mustang5L5 said:
Scope creep has set in.

Now that was fast!! Lol

Willybill32 · Feb 13, 2023

Mustang5L5 said:
Ended up pulling the other side of the exhaust off. I needed access to pull the LCA off and to drill out the broken seat belt bolt plate.

Some might remember I snapped the head off the seatbelt bolt and couldn’t get this out. So I got my hands on some new plates and am just going to weld the new one in place

So now everything is wide open. I have clear access to those inside welds on the SFCs. My flowmasters were just in too close to get the right angle. Now I just need to prep and do some welding.

I’ll prob clean up some of the brackets under here. And replace the fuel filter.

Scope creep has set in.

We’ll, since you’re already in there…!

K&K has my ‘86, and I keep adding things for him to do “since he’s already in there!”

Bill

bird_dog0347 · Feb 13, 2023

I love your attention to detail, it's overkill, but if it's worth killing it's worth overkilling!

Build Thread Mustang5L5's Build Thread -

I was uncomfortably high & wearing a helmet

That is…until I whipped out my Bissell

still married haven't seen testicles in years

I was uncomfortably high & wearing a helmet

That is…until I whipped out my Bissell

lube between the nut and the face. I know my lubes

Mustang Master

But at least it's tight!

But at least it's tight!

wrap a little cheese around it and its a done

Been here over a DECADE and still no CT

That is…until I whipped out my Bissell

That is…until I whipped out my Bissell

That is…until I whipped out my Bissell

That is…until I whipped out my Bissell

That is…until I whipped out my Bissell

So while I wait to figure out my rear end issues

But at least it's tight!

still married haven't seen testicles in years

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